Research Findings - Epidemiology and Etiology Research

Subtypes of Drug Users

This article applies methods of latent class analysis (LCA) to data on lifetime illicit drug use in order to determine whether qualitatively distinct classes of illicit drug users can be identified. Self-report data on lifetime illicit drug use (cannabis, stimulants, hallucinogens, sedatives, inhalants, cocaine, opioids and solvents) collected from a sample of 6265 Australian twins (ages 24-36) were analyzed using LCA. Rates of childhood sexual and physical abuse, lifetime alcohol and tobacco dependence, symptoms of illicit drug abuse/dependence and psychiatric comorbidity were compared across classes using multinomial logistic regression. LCA identified a 5-class model: Class 1 (68.5%) had low risks of the use of all drugs except cannabis; Class 2 (17.8%) had moderate risks of the use of all drugs; Class 3 (6.6%) had high rates of cocaine, other stimulant and hallucinogen use but lower risks for the use of sedatives or opioids. Conversely, Class 4 (3.0%) had relatively low risks of cocaine, other stimulant or hallucinogen use but high rates of sedative and opioid use. Finally, Class 5 (4.2%) had uniformly high probabilities for the use of all drugs. Rates of psychiatric comorbidity were highest in the polydrug class although the sedative/opioid class had elevated rates of depression/suicidal behaviors and exposure to childhood abuse. The authors conclude that aggregation of population-level data may obscure important subgroup differences in patterns of illicit drug use and psychiatric comorbidity, that LCS may help distinguish useful subtypes, and that further exploration of a "self-medicating" subgroup is needed. Lynskey, M., Agrawal, A., Bucholz, K., Nelson, E., Madden, P., Todorov, A., Grant, J., Martin, N., and Heath, A. Subtypes of Illicit Drug Users: A Latent Class Analysis of Data from an Australian Twin Sample. Twin Res Hum Genet, 9(4), pp. 523-530, 2006.

Drug Abuse Outcomes Associated with ADHD Subtypes in the Community

This study used data from a relatively large, community-identified longitudinal sample of children with attention-deficit/hyperactivity disorder (ADHD) to describe the late adolescent drug use outcomes associated with this disorder. Subjects have been assessed from childhood through late adolescence, and outcomes compared between ADHD-only (n = 27), ADHD-externalizing (mostly oppositional defiant disorder) (n = 82), and normal control (n = 91) groups. The ADHD-externalizing group revealed significantly worse drug use outcomes (drug use frequency and substance use disorders) compared to the other two groups, and the ADHD-only group showed outcomes comparable to the community control group. The authors conclude that ADHD without a comorbid externalizing disorder is not associated with an increased risk of drug abuse, while ADHD with a comorbid externalizing disorder, primarily oppositional defiant disorder, is associated with an elevated risk of drug use, particularly with respect to marijuana and tobacco involvement. The use of a community-based sample augments the generalizability of these findings, which hold great potential to clarify which subgroups of children are at risk for later drug use disorders, and suggest that ADHD, when uncomplicated by another externalizing disorder, is not a risk factor for drug abuse. August, G., Winters, K., Realmuto, G., Fahnhorst, T., Botzet, A., and Lee, S. Prospective Study of Adolescent Drug Use Among Community Samples of ADHD and Non-ADHD Participants. J Am Acad Child Adolesc Psychiatry, 45(7), pp. 824-832, 2006.

Genetic and Environmental Vulnerabilities Underlying Adolescent Substance Use and Problem Use: General or Specific?

Are genetic and environmental risks for adolescent substance use specific to individual substances or general across substance classes? Researchers examined this question in 645 monozygotic twin pairs, 702 dizygotic twin pairs, 429 biological sibling pairs, and 96 adoptive (biologically unrelated) sibling pairs ascertained from community-based samples, and ranging in age from 12 to 18 years. Substance use patterns and symptoms were assessed using structured psychiatric interviews. Biometrical model fitting was carried out using age- and sex-specific thresholds for (a) repeated use and (b) problem use, defined as one or more DSM-IV symptoms of abuse or dependence. The researchers hypothesized that problem use would be more heritable than use in adolescence, and that both genetic and environmental risks underlying tobacco, alcohol, and marijuana use and problem use would be significantly correlated. Results of univariate analyses suggested significant heritable factors for use and problem use for all substances with the exception of alcohol use. Shared environmental factors were important in all cases and special twin environmental factors were significant for tobacco use, tobacco problem use, and alcohol use. Multivariate analyses yielded significant genetic correlations between each of the substances (for both levels studied), and significant shared environmental correlations among use variables only. These results suggest that tobacco, alcohol, and marijuana problem use are mediated by common genetic influences, but shared environmental influences may be more substance-specific for problem use. Young, S., Rhee, S., Stallings, M., Corley, R., and Hewitt, J. Genetic and Environmental Vulnerabilities Underlying Adolescent Substance Use and Problem Use: General or Specific? Behav Genet, 36(4), pp. 603-615, 2006.

Strong Evidence of Links Between Child Maltreatment and Adolescent Substance Abuse

The purpose of this study was to estimate the prevalence of child maltreatment in the United States and examine its relationship to sociodemographic factors and major adolescent health risks. The National Longitudinal Study of Adolescent Health is a prospective cohort study following a national sample of adolescents into adulthood. The wave III interview, completed by 15,197 young adults in 2001-2002 (77.4% response rate), included retrospective measures of child maltreatment. Authors used these measures to estimate the prevalence of self-reported supervision neglect, physical neglect, physical assault, and contact sexual abuse during childhood. Next, they investigated the relationship between sociodemographic characteristics and maltreatment. Finally, they examined the association between child maltreatment and adolescent self-rated health; overweight status; depression; cigarette, alcohol, marijuana, and inhalant use; and violent behavior. Having been left home alone as a child, indicating possible supervision neglect, was most prevalent (reported by 41.5% of respondents), followed by physical assault (28.4%), physical neglect (11.8%), and contact sexual abuse (4.5%). Each sociodemographic characteristic was associated with > or = 1 type of maltreatment, and race/ethnicity was associated with all 4. Each type of maltreatment was associated with no fewer than 8 of the 10 adolescent health risks examined. Self-reported childhood maltreatment was common. The likelihood of maltreatment varied across many sociodemographic characteristics. Each type of maltreatment was associated with multiple adolescent health risks. Hussey, J., Chang, J., and Kotch, J. Child Maltreatment in The United States: Prevalence, Risk Factors, and Adolescent Health Consequences. Pediatrics, 118(3), pp. 933-942, 2006.

Role of Poverty in Adolescents Weight

Prevalence of adolescent's weight issues in the United States has increased substantially during the past 3 decades. Whether socioeconomic disparities in adolescents increased, decreased, or remained constant during this period is not known. The objective of this study is to examine trends in weight issues among adolescents from 1971 to 2004 by family poverty status, as well as trends in potentially relevant eating and physical activity behaviors. Four cross-sectional, nationally representative surveys (US National Health and Nutrition Examination Surveys [NHANES] of 1971-1974, 1976-1980, 1988-1994, and 1999-2004) were examined for trends in the prevalence of weight among adolescents aged 12 to 17 years by family poverty status. Main outcome measures include prevalence of adolescent weight issues, defined as body mass index at or above the 95th percentile for age and sex in the 2000 Centers for Disease Control and Prevention growth charts; intermediate outcomes include physical inactivity in the past 30 days, proportion of caloric intake from sweetened beverages (24-hour recall), and whether respondent skipped breakfast (24-hour recall). Results suggest trends in the association of adolescent weight issues with family poverty differed by age stratum (P = .01). In 12- to 14-year-old adolescents, prevalence did not significantly differ by family poverty status in any of the surveys; however, among non-Hispanic black adolescents, overweight prevalence increased faster in nonpoor vs poor families. In contrast, a widening disparity that disfavored adolescents from poor families was present in the 15- to 17-year-old adolescents. This trend was similar among male, female, non-Hispanic white, and non-Hispanic black adolescents, resulting in an overall prevalence of overweight in 1999-2004 more than 50% higher among adolescents in poor vs nonpoor families (23.3% vs 14.4%, respectively; P<.001). Additional analyses suggest that physical inactivity, sweetened beverage consumption, and skipping breakfast may contribute to these disparities. Trends of increasing overweight showed a greater impact in families living below the poverty line vs not living below the poverty line among older (15-17 years) but not younger (12-14 years) adolescents. Furthermore, physical inactivity, high consumption of sweetened beverages, and breakfast skipping may be candidate targets for prevention programs aimed at reducing this recently emerged disparity. Miech, R., Kumanyika, S., Stettler, N., Link, B., Phelan, J., and Chang, V. Trends in The Association of Poverty with Overweight Among US Adolescents, 1971-2004. JAMA, 295(20), pp. 2385-2393, 2006.

Comorbidity Between Alcohol Dependence and Illicit Drug Dependence in Adolescents with Antisocial Behavior and Matched Controls

While comorbidity among substance use disorders is common, the causes have not been clear, and prior literature has been conflicting regarding the role of familial influences on common or substance-specific liability. This study addressed the issue using a clinical sample of 272 adolescents ages 13-20, treated for antisocial behavior and substance use disorders, and their siblings and a matched control sample. A model fitting approach was used to test 13 alternative hypotheses for the causes of comorbidity. The best supported hypothesis for the comorbidity between alcohol dependence and illicit drug dependence was a model hypothesizing that comorbid disorders are alternate forms of a single underlying liability. The next best fitting models were two of the correlated liabilities models (correlated risk factors and reciprocal causation). These results suggest that the best hypotheses explaining the comorbidity between alcohol and illicit drug dependence in antisocial adolescents are that alcohol dependence and illicit drug dependence are manifestations of a single general liability to develop substance dependence or that there are separate liabilities that are highly correlated. Although these findings may not generalize to adults or to individuals without severe antisocial personality disorders, they may help point the way to approaches for searching for genes for this common liability. Rhee, S., Hewitt, J., Young, S., Corley, R., Crowley, T., Neale, M., and Stallings, M. Comorbidity Between Alcohol Dependence and Illicit Drug Dependence in Adolescents with Antisocial Behavior and Matched Controls. Drug Alcohol Depend, 84 (1), pp. 85-92, 2006.

Genetic and Cultural Transmission of Smoking Initiation

This study used an extended kinship design to examine the role of genetic and environmental factors for smoking initiation. The authors report that this design can take into account factors including assortative mating and parent-offspring transmission beyond what has been reported in traditional twin and adoption genetic epidemiologic studies. Data were collected by questionnaires from 14,763 twins and their parents, spouses, children, and siblings, for a total of 28,492 individuals from 8567 extended kinships. 58% of the sample was female and 50% were under the age of 50. Extensive modeling found that both genetic and environmental factors play a significant role in the liability to smoking initiation. This study showed significant heritability, partly due to assortment, and significant effects of primarily non-parental shared environment on smoking initiation. While confirming that genetic factors account for the majority of individual differences in liability to smoking initiation, the authors found that shared environmental factors do play a significant role, primarily due to within-generational influences, e.g. siblings and co-twins. The association between smoking behavior in parents and their children can be most likely accounted for by their genetic relatedness. The idea of social learning in smoking may apply to siblings or peers but does not appear to apply to children learning by modeling from their parents. Maes, H.H., Neale, M.C., Kendler, K.S., Martin, N.G., Heath, A.C., and Eaves, L.J. Genetic and Cultural Transmission of Smoking Initiation: An Extended Twin Kinship Model. Behav Genet, 36(6), pp. 795-808, 2006.

Reinterpreting Ethnic Patterns among White and African American Men Who Inject Heroin: A Social Science of Medicine Approach

Street-based heroin injectors represent an especially vulnerable population subject to negative health outcomes, including HIV/AIDS and other infectious diseases, and social stigma. Researchers used a multi-method approach to examine quantitative, clinical, and ethnographic data collected from 2 contemporaneous long-term studies in San Francisco, one epidemiological and one ethnographic. Both studies explored the impact of ethnicity on street-based heroin-injecting men (N=1,068), 45 years of age or older who were self-identified as either African American (n=453 or 42%) or White (n=614 or 57%). After stratifying 14 relevant epidemiological variables by median age and ethnicity, the researchers found significant differences in social practices between self-identified African Americans and Whites, particularly with respect to patterns of drug consumption; income generation; social and institutional relationships; and personal health and hygiene. African Americans and whites tended to experience different structural relationships to their shared condition of addiction and poverty. Specifically, African Americans had earlier and more negative contact with law enforcement but maintained long-term ties with their extended families. Most of the Whites, by contrast, were expelled from their families when they began engaging in drug-related crime. The authors argue that historical-structural conditions generate distinct presentations of addiction, with Whites styling themselves as outcasts, defeated by addiction, and injecting to stave off ''dope sickness,'' and African Americans casting their addiction as an oppositional pursuit of autonomy and pleasure. The researchers discuss how bringing quantitative and qualitative methods and perspectives together in such an analysis yields insights and discoveries that would otherwise not be possible. Specifically, a clinical social science approach provides insights into how socio-cultural processes are mediated by historically rooted and institutionally enforced power relations. Bourgois, P., Martinez, A., Kral, A., Edlin, B., Schonberg, J., and Ciccarone, D. Reinterpreting Ethnic Patterns Among White and African American Men Who Inject Heroin: A Social Science of Medicine Approach. PLoS Medicine, 3(10), pp. 1805-1815, 2006.

Modeling Initation and Progression of Substance Use and Abuse

The authors note that twin data can provide valuable insight into the relationship between the stages of phenomena such as substance abuse, but existing models for the relationship between initiation and progression have been difficult to extend because they are usually expressed in terms of explicit integrals. In this paper, the problem is overcome by regarding the analysis of twin data on initiation and progression as a special case of missing data, in which individuals who do not initiate are regarded as having missing data on progression measures. Using the general framework for the analysis of ordinal data with missing values available in Mx makes extensions that include other variables much easier. The effects of continuous covariates such as age on initiation and progression becomes simple. Also facilitated are the examination of initiation and progression in two or more substances, and transition models with two or more steps. This paper describes and then applies these methods to twin data from 1942 adult female twins in the Virginia Twin Registry; models studied the effects of cohort on liability to cannabis use and abuse, bivariate analysis of tobacco use and dependence and cannabis use and abuse, and the relationships between initiation of smoking, regular smoking and nicotine dependence. In addition to the methodologic advances, this article offers substantive findings including a strong relationship between initiation of cannabis and smoking, and a stronger relationship between smoking initiation and regular smoking than either with nicotine dependence. These new methods hold much promise for making use of existing data and advancing our understanding of drug use progression and phenotypes. Neale, M., Harvey, E., Maes, H., Sullivan, P., and Kendler, K. Extensions To The Modeling of Initiation And Progression: Applications To Substance Use and Abuse. Behav Genet, 36(4), pp. 507-524, 2006.

Childhood Trauma Among Incarcerated Women in Substance Abuse Treatment

Authors sought to describe the prevalence of childhood traumatic events among incarcerated women in substance abuse treatment and to assess the relation between cumulative childhood traumatic events and adult physical and mental health problems. The study was modeled after the Adverse Childhood Events study's findings. In-depth baseline interview data for 500 women participating in the Female Offender Treatment and Employment Program evaluation were analyzed. Hypotheses were supported, and regression results showed that the impact of childhood traumatic events on health outcomes is strong and cumulative (greater exposure to childhood traumatic events increased the likelihood of 12 of 18 health-related outcomes, ranging from a 15% increase in the odds of reporting fair/poor health to a 40% increase in the odds of mental health treatment in adulthood). These findings suggest a need for early prevention and intervention, and appropriate trauma treatment, within correctional treatment settings. Messina, N., and Grella, C. Childhood Trauma and Women's Health Outcomes in a California Prison Population. Am J Public Health, 96(10), pp. 1842-1848, 2006.

College Students' Illicit Use of Specific Prescription Stimulants

To explore the illicit use of specific prescription stimulants among college students and add to our understanding of reasons (motives) and routes of administration associated with illicit use of these drugs. A random sample of 4580 college students self-administered a Web-based survey. The survey contained a variety of items pertaining to the illicit use of prescription stimulants. An extensive list of prescription stimulants was provided, and students were asked to select all the specific prescription stimulants that they had used illicitly. Items were also included to assess the motives and routes of administration associated with illicit use of prescription stimulants. Lifetime and past-year prevalence rates for illicit use of prescription stimulants were 8.3% (382 students) and 5.9% (269 students), respectively. Approximately three fourths (75.8%) of the 269 past-year illicit users of prescription stimulants reported using an amphetamine-dextroamphetamine combination agent (e.g., Adderall) in the past year, and approximately one fourth (24.5%) reported using methylphenidate (e.g., Ritalin, Concerta, Metadate, Methylin). Past-year illicit use of prescription stimulants was more than 3 times more likely among Caucasians (odds ratio [OR] 3.1, 95% confidence interval [CI] 1.5-6.6) and Hispanics (OR 3.8, 95% CI 1.6-9.3) compared with African-Americans, and more than twice as likely among Caucasians (OR 2.1, 95% CI 1.3-3.4) and Hispanics (OR 2.6, 95% CI 1.4-5.1) compared with Asians. The most commonly reported motives for illicit use were to help with concentration (65.2%), help study (59.8%), and increase alertness (47.5%). Other motives included getting high (31.0%) and experimentation (29.9%). Nearly every illicit user (95.3%) reported oral administration, and 38.1% reported snorting prescription stimulants. Illicit use of amphetamine-dextroamphetamine is more prevalent than illicit use of methylphenidate formulations among college students. Teter, C., McCabe, S., Lagrange, K., Cranford, J., and Boyd, C. Illicit Use of Specific Prescription Stimulants Among College Students: Prevalence, Motives, and Routes of Administration. Pharmacotherapy, 26(10), pp. 1501-1510, 2006.

DAST Drug Abuse Screening of College Students

The present study assesses the prevalence of items from a modified version of the Drug Abuse Screening Test, Short Form (DAST-10) for substances other than alcohol among undergraduate students. More than 4,500 undergraduate students at a large Midwestern research university completed a web-based survey in 2005. Nearly 1 in every 10 undergraduate students experienced three or more DAST-10 items in the past 12 months. Although the prevalence of illicit drug use did not differ by gender, undergraduate men were significantly more likely than women to report DAST-10 items. Less than 6% of individuals who reported three or more drug DAST-10 items had ever used treatment services for substance use. As a brief screening instrument, the DAST-10 offers promise for detecting possible drug abuse among college students. Based on the prevalence of drug use, colleges and universities are encouraged to provide screening opportunities to identify and to provide services for students at high risk for drug abuse. McCabe, S., Boyd, C., Cranford, J., Morales, M., and Slayden, J. A Modified Version of The Drug Abuse Screening Test Among Undergraduate Students. J Subst Abuse Treat, 31(3), pp. 297-303, 2006.

Behavioral and Emotional Self-Control: Relations to Substance Use in Samples of Middle and High School Students

The authors tested how behavioral and emotional self-control are related to adolescent substance (tobacco, alcohol, and marijuana) use. Data were obtained from 489 middle school students and 602 high school students. Multiple indicators were developed for each domain of self-control, and confirmatory analyses were used to test the measurement structure of latent constructs. Results showed that the domains of behavioral self-control and emotional self-control were statistically distinct, and both were related to adolescent substance use. Structural modeling analyses indicated indirect effects for self-control constructs primarily through pathways to competence and recent events. In addition, poor behavioral control had a direct effect to deviant peer affiliations, and poor emotional control had a direct effect to coping motives for substance use. The results indicate that both types of self-regulation are relevant for adolescent substance use. Implications for prevention and treatment research are discussed. Wills, T., Walker, C., Mendoza, D., and Ainette, M. Behavioral and Emotional Self-Control: Relations to Substance Use in Samples of Middle and High School Students. Psychol Addict Behav, 20(3), pp. 265-278, 2006.

Inhalant Use and Disorders among Adults in the US

This paper examines patterns of adult inhalant use and correlates of inhalant use disorder. Data were drawn from the 2002 and 2003 National Surveys on Drug Use and Health (NSDUH) and logistic regression was used to identify the characteristics associated both with inhalant use and inhalant use disorder. Study findings indicate that 1 in 10 of all adults had used an inhalant at least once in their lives, and 0.5% used one in the past year. Among all past year inhalant users, 8% met the criteria for an inhalant use disorder (i.e., 6.6% for abuse and 1.1% for dependence) within that period. There was an increased prevalence of past year inhalant use among young adults aged 18-25 years, Asians, past year alcohol abusers and dependents, lifetime drug users, white women, and men reporting symptoms of serious mental illness. Inhalant-using adults who met the criteria for an inhalant use disorder were predominantly adults aged 35-49 years and were less educated, had received recent professional treatment for emotional or psychological problems, used inhalants weekly, and had a coexisting alcohol use disorder. The authors conclude that the patterns and consequences of adult inhalant use differ from those of adolescents. Compared with adolescent inhalant users, adult users tend not to initiate inhalant use until adulthood, use inhalants less frequently, use fewer inhalants, and are less likely to engage in criminal activities. Wu, L. and Ringwalt, C. Inhalant Use and Disorders among Adults in the United States. Drug Alcohol Depend, 85(1), pp. 1-11, 2006.

Magazine Advertising and Adolescent Cigarette Smoking

The purpose of the present study is to examine the relation between magazine advertising for cigarettes and adolescent cigarette smoking. Participants (242 adolescents) reported their frequency of reading 46 magazines and their attention to cigarette ads. Recognition of cigarette ads, passive peer pressure (i.e., normative beliefs), and the smoker image also were assessed. Results indicate that exposure to cigarette advertising and recognition of ads augment the effect of passive peer pressure on smoking. In addition, a positive smoker image was associated with attention to advertising and mediated the relation between attention and smoking. It is suggested that the effect of magazine ads on adolescents should be considered in policymaking on cigarette advertising. Aloise-Young, P., Slater, M., and Cruickshank, C. Mediators and Moderators of Magazine Advertisement Effects on Adolescent Cigarette Smoking. J Health Commun, 11(3), pp. 281-300, 2006.

The Lifetime Cost of Current Human Immunodeficiency Virus Care in the United States

This collaborative effort, supported by NIDA, NIAID, and the AHRQ, sought to project the lifetime cost of medical care for HIV-infected adults using current antiretroviral therapy (ART) standards. Medical service utilization, including visits and hospitalizations for any reason, were estimated from cross-sectional data collected by the HIV Research Network, a consortium of high-volume HIV primary care sites. HIV treatment drug regimen efficacies were obtained from clinical guidelines and published sources. In a computer simulation model, researchers projected HIV medical care costs in 2004 U.S. dollars. They found that, from the time of entering HIV care, per person projected life expectancy is 24.2 years, discounted lifetime cost is $385,200, and undiscounted cost is $618,900 for adults who initiate ART with CD4 cell count <350/muL. An estimated 73% of the cost is on antiretroviral medications; 13% inpatient care; 9% outpatient care; and 5% other HIV-related medications and laboratory costs. For patients who initiate ART with CD4 cell count <200/muL, projected life expectancy is 22.5 years, discounted lifetime cost is $354,100 and undiscounted cost is $567,000. The results are sensitive to drug manufacturers' discounts, ART efficacy, and if the efficacy of ART regimens declines, whether the 4th line regimen includes enfuvirtide for salvage. If costs are discounted to the time of infection, the discounted lifetime cost is $303,100. These findings demonstrate the remarkable clinical benefit of ART in substantially improving survival. Not only is ART the most costly component of care, but individuals are incurring these costs over more years due to improved life expectancies. Schackman, B.R. , Gebo, K.A. , Walensky, R.P. , Losina, E. , Muccio, T. , Sax, P.E. , Weinstein, M.C. , Seage, G.R. 3rd , Moore, R.D., and Freedberg, K.A. The Lifetime Cost of Current Human Immunodeficiency Virus Care in the United States. Med Care, 44(11), pp. 990-997, 2006.

The Role of Parenting in Drug Use among Black, Latino, and White Adolescents

This study investigates the role of parenting in adolescent drug use for black, white and Latino adolescents. Parenting has been consistently identified as a crucial factor in drug use by adolescents. This study uses data from the National Longitudinal Study of Adolescent Health. Results show that parenting has a significant effect on drug use for these adolescents. The relationship between parenting and drug use is more strongly negative for the Latino adolescents, than for black and white adolescents. This indicates that greater parental warmth and family acceptance exert a stronger impact in reducing drug use for Latino adolescents than is the case for the black and white adolescents. Broman, C., Reckase, M., and Freedman-Doan, C. The Role of Parenting in Drug Use Among Black, Latino and White Adolescents. J Ethn Subst Abuse, 5(1), pp. 39-50, 2006.

Parent Psychopathology, Parenting and Internalizing Problems among Children of Substance Abusers

A structural model accounting for child internalizing problems in substance-abusing families was tested. Parents receiving substance abuse treatment (N = 242) completed forms about children between the ages of 6 and 18 who resided in their home. The effects of parent gender, child gender, and child age were controlled. Negative parenting was examined as a mediator between parent internalizing and externalizing problems and child anxiety and affective problems using path analysis. Negative parenting mediated relations only between parent internalizing problems and child affective problems. High-positive involvement moderated relations between parent externalizing problems and child internalizing problems. Relations between parent externalizing problems and child anxiety and affective problems were significant only among families in which high-positive involvement was present. Burstein, M., Stanger, C., Kamon, J., and Dumenci, L. Parent Psychopathology, Parenting, and Child Internalizing Problems in Substance-Abusing Families. Psychol Addict Behav, 20(2), pp. 97-106, 2006.

Parents and Families as Contexts for the Development of Substance Use and Substance

Use Disorders Parenting and familial influences on substance use and substance use disorders (SUDs) are important areas of study both for theories of etiology and for the development of preventive and treatment interventions. The articles in this special section illustrate both the value and the challenges of studying parenting and familial influences. Noteworthy issues include the need for mediational and moderational models examining the processes by which familial influences operate in a longitudinal framework to consider outcomes in a developmental context. Future directions include a multidisciplinary expansion of these studies. Chassin, L., and Handley, E. Parents and Families as Contexts for the Development of Substance Use and Substance Use Disorders. Psychol Addict Behav, 20(2), pp. 135-137, 2006.

Substance Abusing Mothers and Disruptions in Child Custody

Using an attachment framework, authors examined (1) whether substance-abusing mothers' perceptions of how they were parented were related to the severity of their substance abuse and psychological maladjustment and (2) whether these two factors mediated the association between mothers' perceptions of how they were parented and their childrens' placement out of home. There were 108 mothers of 248 children who completed interviews upon admission to a methadone maintenance program for women. A multilevel modeling approach was used to model effects of the hierarchically organized data (e.g., children nested within families). Findings are consistent with an attachment perspective on parenting suggesting that the internal psychological processes of a parent play a critical role in the continuity of parenting. When multiple risk domains associated with children's out-of-home placement were examined together within the same statistical model, maternal substance abuse severity and psychological maladjustment were the strongest predictors of children's out of home placement. Furthermore, mothers who perceived their own mothers as uncaring and intrusive were more likely to have lost custody of a minor child. There was also evidence that this effect was partially mediated by maternal substance abuse severity and psychological maladjustment. Suchman, N., McMahon, T., Zhang, H., Mayes, L., and Luthar, S. Substance-Abusing Mothers and Disruptions in Child Custody: An Attachment Perspective. J Subst Abuse Treat, 30(3), pp. 197-204, 2006.

Parent-Child Attachment, Parenting, Family Ecology and Persistent Conduct Problems

A small proportion of children exhibit extreme and persistent conduct problems through childhood. The present study employed the multiple-domain model of Greenberg and colleagues as the framework for person-oriented analyses examining whether parent-child attachment combines with parenting, family ecology, and child characteristics in particular configurations of risk that are linked to this problematic developmental pathway. Using prospective data from a community sample of adolescent mothers and their children (n=255), latent variable growth mixture modeling identified a normative trajectory with declining problem behaviors during the preschool period. Consistent with research on early-starter pathways, a distinct group of children featured a higher intercept and a positive slope, indicating an escalation in disruptive behaviors. Attachment security played a role in defining specific risk profiles associated with the probability of exhibiting this problem trajectory. Given particular patterns of risk exposure, secure attachment served a protective function. Avoidant, but not disorganized, attachment was associated with significantly higher likelihood of the disruptive problem trajectory. The results also indicated the general accumulation of risk was detrimental, but the particular configuration of risk made a difference. Overall, the findings suggest that early attachment operates in conjunction with personal and contextual risk to distinguish the development of later problem behaviors. Keller, T., Spieker, S., and Gilchrist, L. Patterns of Risk and Trajectories of Preschool Problem Behaviors: A Person-oriented Analysis of Attachment in Context. Dev Psychopathol, 17(2), pp. 349-384, 2005.

Early Risk Factors Predict Success in Transition to Adulthood Among Adolescent Mothers

This prospective longitudinal study is based on a diverse sample of adolescent mothers in the Northwest. Data have been collected from pregnancy through adulthood. Five risk factors were used (individually and in a cumulative risk index) to predict young mothers' life course pathways from age 17 through 23 years. A multinomial logistic regression indicated that, relative to the normative group, the problem-prone group had significantly greater odds of having a history of school problems, delinquency, and hard substance use. The psychologically vulnerable group had significantly greater odds of mental health problems, hard substance use, and marginally more delinquency. Importantly, the cumulative risk index (the sum of the five risk factors) predicted the patterns of transition into adulthood and demonstrated significant sensitivity and specificity in distinguishing those in the normative pathway from those in either the problem-prone or psychologically vulnerable pathway. Results suggest that specific risk factors assessed at pregnancy can differentiate among adolescent mothers who experience varying levels of success in their transition into early adulthood. The cumulative risk index demonstrates applied utility as a risk assessment tool capable of distinguishing among life-course pathways. Oxford, M., Gilchrist, L., Gillmore, M., and Lohr, M. Predicting Variation in the Life Course of Adolescent Mothers as they Enter Adulthood. J Adolesc Health, 39(1), pp. 20-26, 2006.

Associations Among Familial Alcoholism, Parent Socialization and Children's Adjustment, Coping Style and Coping Efficacy

The relations of children's coping strategies and coping efficacy to parent socialization and child adjustment were examined in a sample of school-age children that included families in which some of the grandparents and/or parents had an alcoholism diagnosis (n=300). Parents and older children reported on the children's coping strategies; parents reported on their parenting behavior; and teachers reported on children's externalizing and internalizing problems. Measures of parent socialization were associated with parents' and children's reports of active coping strategies and parents' reports of both support-seeking coping and coping efficacy. Some of these relations were moderated by familial alcohol status. Children higher in parent-reported active/support-seeking coping and coping efficacy were rated lower in teacher-reported externalizing and internalizing adjustment problems. The findings were consistent with the view that active/support-seeking coping and coping efficacy mediated the association of parent socialization to children's psychological adjustment and that this relation was sometimes moderated by parental alcohol status. Smith, C., Eisenberg, N., Spinrad, T., Chassin, L., Morris, A., Kupfer, A., Liew, J., Cumberland, A., Valiente, C., and Kwok, O. Children's Coping Strategies and Coping Efficacy: Relations to Parent Socialization, Child Adjustment, and Familial Alcoholism. Dev Psychopathol, 18(2), pp. 445-469, 2006.

Famililal Alcoholism, Family Harmony and Young Adults' Substance Dependence Disorders

This study examined the prospective relations among family history density of alcoholism (FHD), adolescent family harmony, and young adults' (n=246) alcohol and drug dependence. Family harmony was rated by mothers and fathers in adolescence and young adults ' substance dependence diagnoses were obtained through structured interviews. Higher FHD predicted lower adolescent family harmony, which in turn increased young adults' odds of being diagnosed with drug dependence (with and without alcohol dependence) compared to no diagnoses or to alcohol dependence only. Family harmony also interacted with FHD such that the protective effect of family harmony on young adults' drug dependence with or without alcohol dependence decreased as FHD rose, and was nonsignificant at high levels of FHD. The findings suggest the importance of distinguishing among alcohol and drug dependence disorders and examining their differential etiological pathways, and also suggest that the protective effects of harmonious family environments on substance dependence may be limited at high levels of FHD. Zhou, Q., King, K., and Chassin, L. The Roles of Familial Alcoholism and Adolescent Family Harmony in Young Adults' Substance Dependence Disorders: Mediated and Moderated Relations. J Abnorm Psychol, 115(2), pp. 320-331, 2006.

Psychiatric Comorbidity and Progression in Drug Use in Adult Male Twins: Implications for the Design of Genetic Association Studies

Psychiatric comorbidity with drug dependence has been widely documented. In the present study, researchers used latent class methods to reanalyze DSM-III-R diagnostic data on 8,169 middle-aged male twins (3,372 complete twins and 1,425 singletons) from the Vietnam Era Twin Registry Study (VETS). They identified four subtypes based on 15 diagnostic categories, and showed that these subtypes are strongly associated with differential rates of transitions in drug use histories, with increased risks in relatives for depression, alcohol, drug and antisocial personality disorder as well as with a variety of non-normative and deviant behaviors in youth and in adulthood. They then use the result of these analyses to show how the use of a particular drug disorder phenotype for selecting cases could impact final sample composition. These findings suggest that, even though much of the liability to substance dependence may be shared, it appears that the choice of selection phenotype (e.g., opioid vs cannabis dependence) will affect the ultimate sample composition, not only in terms of the propensity to transition to dependence from experimental use, but also in terms of psychiatric comorbidity. Thus, analyses that focus on any substance dependence as the phenotypic endpoint may be introducing substantial heterogeneity into the data. These results indicate that a more controlled sampling scheme should ascertain samples for genetic association studies based on diagnostic profiles rather than on individual diagnoses. Todorov, A., Lynskey, M., Grant, J., Scherrer, J., Todd, R., and Bucholz, K. Psychiatric Comorbidity and Progression in Drug Use in Adult Male Twins: Implications for the Design of Genetic Association Studies. Addict Behav, 31(6), pp. 948-961, 2006.

Heritability of DSM-IV Nicotine Withdrawal

The authors determined the heritability of the eight symptoms of DSM-IV symptoms of nicotine withdrawal in adult twins in the Australian Twin Registry. They examined both the genetic influences on nicotine withdrawal as well as the genetic factors specific to nicotine withdrawal, after controlling for factors responsible for risk of progression beyond experimentation with cigarettes and for quantity smoked (average number of cigarettes per day at peak lifetime use). Epidemiologic and genetic analyses were conducted using telephone diagnostic interview data from young adult Australian twins reporting any cigarette use (3026 women, 2553 men; mean age 30 years). Genetic analysis of the eight symptoms of DSM-IV nicotine withdrawal suggests heritability is intermediate for most symptoms (26-43%), and similar in men and women. The exceptions were depressed mood upon withdrawal, which had stronger additive genetic influences in men (53%) compared to women (29%), and decreased heart rate, which had low heritability (9%). Although prevalence rates were substantially lower for DSM-IV nicotine withdrawal syndrome (15.9%), which requires impairment, than for the DSM-IV nicotine dependence withdrawal criterion (43.6%), heritability was similar for both measures: as high as 47%. Genetic modeling of smoking more than 1 or 2 cigarettes lifetime ( ''progression ''), quantity smoked and nicotine withdrawal found significant genetic overlap across all three components of nicotine use/dependence (genetic correlations = 0.53-0.76). Controlling for factors associated with risk of cigarette smoking beyond experimentation and quantity smoked, evidence for genetic influences specific to nicotine withdrawal (up to 23% of total variance) remained. Their results suggest that at least some individuals become ''hooked '' or progress in the smoking habit, in part, because of a vulnerability to nicotine withdrawal. Pergadia, M., Heath, A., Martin, N., and Madden, P. Genetic Analyses of DSM-IV Nicotine Withdrawal in Adult Twins. Psychol Med, 36(7), pp. 963-972, 2006.

Examination of the Underlying Liability and Symptom Patterns among Syndromes of Substance Use Disorder for Illicit Drugs

The use of DSM criteria to evaluate liability to substance use disorders (SUDs) and to identify SUD phenotypes may not provide the sensitivity required to identify genes associated with vulnerability to SUDs. The authors of this study evaluated a number of basic aspects of substance use that may be more proximal than full SUDs to risk genes, some of which may thus have greater potential utility as phenotypes in subsequent molecular genetic analyses. In this paper they focused on how individual symptoms of abuse and dependence may be used to create alternate phenotypes for SUDs. Specifically, they used factor analysis and biometrical modeling on each symptom of illicit substance abuse and dependence within different types of substances, and compared and contrasted factor patterns and heritabilities across the different substances. These analyses were carried out using a population-based sample of 3372 male-male twin pairs from the Vietnam Era Twin Registry who participated in the Harvard Twin Study of Substance Abuse. Via telephone interview in 1992, they obtained extensive data on substance use and SUDs including opiates, cocaine, cannabis, sedatives, stimulants, and psychedelics. The results indicate that: A) although a one-factor model assuming a single underlying liability for abuse and dependence symptoms and behaviors can be rejected for most substances, there is no uniform support for a two-factor model differentiating between abuse versus dependence; B) patterns of symptoms or behaviors reported by substance users vary across substances; C) not all symptoms or behaviors contribute equally to the presentation of an SUD; and D) the heritability of symptoms or behaviors of substance users varies both within and between substances. These results represent important first steps in facilitating the search for SUD-risk genes in subsequent high-throughput molecular genetic analyses by providing alternate phenotypes that may have both optimal validity and increased heritability. Beseler, C., Jacobson, K., Kremen, W., Lyons, M., Glatt, S., Faraone, S., Gillespie, N., and Tsuang, M. Is there Heterogeneity Among Syndromes of Substance Use Disorder for Illicit Drugs? Addict Behav, 31(6), pp. 929-947, 2006.

Examination of Transitions from Initiation through Dependence in Adolescent Substance Involvement

The present study examined Lengths of Times for important transitions in substance involvement from Initiation to Regular use (LOTIR), first Problem from drug use (LOTIP), and first experience of Dependence (LOTID) for alcohol, tobacco, cannabis, cocaine, and opiates. Data were from a longitudinal study of 590 children (22.2% female) at different levels of risk for substance use disorders based on their fathers' substance use-related diagnoses. Participants' substance involvement was assessed at four ages: 10-12, and follow-ups at two, five, and eight years later. Results suggested that faster transitions were more due to drug-related constructs (including possible social milieus of different drug classes and interactions between drug class and neurophysiology) than intrapersonal constructs. The shortest transition times (and greatest addictive liabilities) were for opiates followed respectively by cocaine, cannabis, tobacco, and alcohol. Females had shorter transition times, though gender differences were small. Some evidence was found for a familial influence on transition times above what was accounted for by differences between substances. Ridenour, T., Lanza, S., Donny, E., and Clark, D. Different Lengths of Times for Progressions in Adolescent Substance Involvement. Addict Behav, 31(6), pp. 962-983, 2006.

Duration of Cannabis Use as a Possible Phenotype

Although cannabis is the most commonly used illicit drug, duration of cannabis use is typically short, with many of those who initiate cannabis use ceasing use by their late twenties. This paper uses twin data to examine whether duration of cannabis use can be an informative phenotype for future genetic analyses. Data came from an Australian cohort of 2706 pairs of male and female twin's ages 24-36 (688 monozygotic female, 503 dizygotic female, 484 monozygotic male, 388 dizygotic male, 643 opposite sex) who were assessed for duration of cannabis use and dependence symptoms. Genetic modeling indicated moderate genetic influences on duration of cannabis use in both males (41%) and females (55%), and strong genetic influences on cannabis dependence in both males (72%) and females (62%). A substantial component of genetic influences on duration of cannabis use was shared with those influencing liability to cannabis dependence, but the overlap is not complete. The authors conclude that lifetime duration of cannabis use may constitute a novel phenotype that can be uniquely informative in assessing components of liability to cannabis use. Lynskey, M., Grant, J., Nelson, E., Bucholz, K., Madden, P., Statham, D., Martin, N., and Heath, A. Duration of Cannabis Use--A Novel Phenotype? Addict Behav, 31(6), pp. 984-994, 2006.

Cessation of Injection Drug Use and Change in Injection Frequency: the Chicago Needle Exchange Evaluation Study

Researchers examined the effect of a needle exchange program (NEP) on incidence of injection cessation and change in injection frequency; explored predictors for injection cessation and change in injection frequency; and assessed whether injection quitters transitioned to non-injected drug use. Between 1997-2002, 901 injection drug users (IDUs) were recruited from an NEP program or an area with no NEP in Chicago, Illinois, interviewed for drug use behaviors, tested for HIV, and followed for 3 annual visits. All participants were exposed to prevention services targeting HIV and drug abuse. Injection cessation was defined as no injection drug use since the last interview, and changes in the number of injections in a typical month were examined. The study found that 16% of study participants reported stopping injection, for a median duration of 16 months, and most of them also ceased rather than initiated the use of non-injected drugs. Those who continued injecting reduced their injection frequency by 12% per year, on average. Independent predictors of injection cessation were infrequent injection at baseline, younger age and injecting with others. NEP use was not associated with injection cessation and change in injection frequency. These results do not support the hypothesis that NEP use influences the frequency of injection over time. Rather, one-sixth of IDUs stopped injection for more than 1 year, providing a substantial window for relapse prevention interventions. Huo, D., Bailey, S., and Ouellet, L. Cessation of Injection Drug Use and Change in Injection Frequency: The Chicago Needle Exchange Evaluation Study. Addiction, 101(11), pp. 1606-1613, 2006.

A Longitudinal Study of Syringe Acquisition by Puerto Rican Injection Drug Users in New York and Puerto Rico: Implications for Syringe Exchange and Distribution Programs

The purpose of this study is to examine changes during a 3-year period in syringe acquisition by street-recruited Puerto Rican IDUs characterized by frequent drug injection and high HIV seroprevalence. At baseline (1998-1999) and 36-month follow-up, 103 IDUs recruited in East Harlem, New York (NY), and 135 from Bayamon, Puerto Rico (PR) were surveyed about syringe sources and HIV risk behaviors in the prior 30 days. A majority of participants in both sites were male (NY 78.6%, PR 84.4%), were born in Puerto Rico (NY 59.2%, PR 87.4%), and had not completed high school (NY 56.3%, PR 51.9%). Compared to PR IDUs at follow-up, NY IDUs injected less (3.4 vs. 7.0 times/day, p < .001), and re-used syringes less (3.1 vs. 8.0 times, p < .001). Between baseline and follow-up, in NY the proportion of syringes from syringe exchange programs (SEPs) increased from 54.2% to 72.9% (p = .001); syringes from pharmacies did not increase significantly (0.2% to 2.5%, p = .095). In PR, the proportions of syringes from major sources did not change significantly: private sellers (50.9% to 50.9%, p = .996); pharmacies (18.6% to 19.0%, p = .867); SEP (12.8% to 14.4%, p = .585). The study indicates that NY SEPs became more dominant, while NY pharmacies remained a minor source even though a law enacted in 2001 legalized syringe purchases without prescription. Private sellers in PR remained the dominant and most expensive source. The only source of free syringes, the SEP, permitted more syringes to be exchanged but the increase was not statistically significant. Implications for syringe exchange and distribution programs are discussed. Finlinson, H., Oliver-Velez, D., Deren, S., Cant, J., Colon, H., Robles, R., Kang, S., and Andia, J. A Longitudinal Study of Syringe Acquisition by Puerto Rican Injection Drug Users in New York and Puerto Rico: Implications for Syringe Exchange and Distribution Programs. Subst Use Misuse, 41(9), pp. 1313-1336, 2006.

Antiretroviral Adherence and HIV Treatment Outcomes among HIV/HCV Co-infected Injection Drug Users: The Role of Methadone Maintenance Therapy

Researchers examined the association of methadone maintenance therapy (MMT) with highly active antiretroviral therapy (HAART) adherence and HIV treatment outcomes among a cohort of HIV/HCV co-infected injection drug users (IDUs). They obtained demographic, drug use, and addiction care history from the Vancouver Injection Drug User Study (VIDUS), which is an open cohort study of IDUs. The questionnaires were longitudinally linked to the British Columbia HIV/AIDS Drug Treatment Program to obtain HAART adherence and HIV treatment outcome data. There were 278 VIDUS participants who accessed HAART from August 1, 1996 to November 24, 2003. Longitudinal logistic models were constructed using generalized estimating equations to examine the independent associations between MMT and the following outcomes: HAART adherence; plasma HIV-1 RNA suppression; and CD4 cell rise of 100cells/mm (3). The study found that, among participants who reported at least weekly heroin use, MMT was independently associated with lower odds of subsequent weekly heroin use during the follow-up period (adjusted odds ratio; 95% confidence interval [AOR; 95% CI]: 0.24; 0.14-0.40). MMT was also positively associated with adherence (AOR 1.52; 95% CI 1.16-2.00), HIV-1 RNA suppression (AOR 1.34; 95% CI 1.00-1.79), and CD4 cell count rise (AOR 1.58; 95% CI 1.26-1.99). These findings indicate that, among HIV/HCV co-infected IDUs on HAART, enrollment in MMT was associated with reduced heroin use, and improved adherence, HIV-1 RNA suppression and CD4 cell count response. Integrating opiate addiction care and HIV care are likely to improve health outcomes for this vulnerable population. Palepu, A., Tyndall, M., Joy, R., Kerr, T., Wood, E., Press, N., Hogg, R., and Montaner, J. Antiretroviral Adherence and HIV Treatment Outcomes among HIV/HCV Co-infected Injection Drug Users: The Role of Methadone Maintenance Therapy. Drug Alcohol Depend, 84(2), pp. 188-194, 2006.

Factors Asociated with Early Adolescent Initiation into Injection Drug Use: Implications for Intervention Programs

This study explores factors associated with early adolescent (aged < or = 16 years) initiation into injection drug use among young (< or = 29 years) injection drug users (IDUs). Data were collected through the Vancouver Injection Drug Users Study (VIDUS). Since 1996, 542 participants aged 29 years and younger have been enrolled and followed. In total, 205 (38%) young participants were initiated at age 16 years or younger. The proportion of young initiators was greater among: females, adjusted odds ratio [AOR]: 1.63 (95% confidence interval [CI]: 1.09-2.44); sex workers, AOR: 1.61 (CI: 1.11-2.31); binge drug users, AOR: 1.45 (CI: 1.01-2.08); and those who have been in juvenile detention or jail, AOR: 1.78 (CI: 1.16-2.66). Early initiates were more likely to be infected with HIV, OR: 2.6 (CI: 1.3-5.0) and hepatitis C virus (HCV), OR: 2.6 (CI: 1.3-5.0). These findings indicate that targeted early interventions are needed, specifically designed for and in collaboration with girls and young women. Miller, C., Strathdee, S., Kerr, T., Li, K., and Wood, E. Factors Associated with Early Adolescent Initiation into Injection Drug Use: Implications for Intervention Programs. J Adolesc Health, 38(4), pp. 462-464, 2006.

Transitions to Injecting Drug Use among Noninjecting Heroin Users: Social Network Influence and Individual Susceptibility

This study sought to determine the incidence/predictors of transitions to injecting among noninjecting heroin users (NIUs). Street-recruited NIUs (N=579) were recruited and interviewed in New York City, March/1996-March/2003, for a prospective cohort study about social network influence (communication promoting injecting; exposure to injectors) on transitions to injecting and on individual susceptibility. Of the 579, 369 (64%) were followed for a mean of 25 months (among 160 former injectors) to a mean of 31 months (among 209 never injectors). The mean number of months followed up was significantly shorter for former injectors compared to never injectors (p<0.001). The study spanned the time of the September 11, 2001 attacks, when it experienced delays and loss of data, records, and contact information; this may explain, in part, why some of the original cohort were lost to follow-up. However, the overall follow-up rate is comparable to that of several other studies of non-treatment recruited drug users in New York City. A transition to injecting was the first drug injection following baseline. Hazards ratios (HRs) (P< 0.05) were estimated by Cox proportional hazards regression, stratified by baseline injecting history. Former-injectors were more likely to transition to injecting (33% or 53/160 vs. 12% or 25/209; 16.0/100 person-years-at-risk [pyar] vs. 4.6/100 pyar; HR = 3.25). Independent predictors among never-injectors included using >or =2 bags of heroin daily (HR = 7.0); social network influence (communication) and homelessness (HR = 6.3); shorter-term heroin use (HR = 5.3); social network influence (exposure) and physically abused (HR = 4.7); friends approve/condone drug injecting (HR = 3.5); lower perceived social distance from injectors (HR = 2.9); and younger age at first heroin use (HR = 1.2). Independent predictors among former-injectors were social network influence (communication) and lower perceived social distance from injectors (HR = 3.4); white race/ethnicity (HR = 2.0); not very afraid of needles (HR = 1.8); and younger age (HR = 1.1). These findings indicate that the risk of initiating injecting was lower than the risk of resuming injecting. Social network influence facilitates transitioning to injecting among those susceptible. Interventions to prevent injecting should address both social network influence and individual susceptibility. Neaigus, A., Gyarmathy, V., Miller, M., Frajzyngier, V., Friedman, S., and Des Jarlais, D. Transitions to Injecting Drug Use Among Noninjecting Heroin Users: Social Network Influence and Individual Susceptibility. J Acquir Immune Defic Syndr, 41(4), pp. 493-503, 2006.

Social Structural and Behavioral Underpinnings of Hyperendemic Hepatitis C Virus Transmission in Drug Injectors

Hepatitis C virus (HCV) is hyperendemic in drug injectors, yet social structural and behavioral factors underlying transmission are not well established. This case-control study of HCV seroconversion in drug injectors focused on transmission within networks. Incident case subjects (n=17) and seronegative control subjects (n=42) reported injection and sex partners and referred as many as 5 for interviewing and blood testing. Nucleotide sequencing was performed on HCV isolates from infected individuals. The study found that 78% of recent injection partnerships involved behavior that could transmit HCV. Case subjects and control subjects were similar demographically and behaviorally. Case subjects, however, had more HCV-infected partners and consequently engaged in injection risk behavior with more infected partners. The injection network was mostly connected, dense, and cyclic, but the sexual network was highly fragmented. Although participants generally injected with partners of similar age, most HCV-uninfected participants recently had injected with infected partners. In at least 1 of 4 pairs of genetically linked infections, transmission appeared to be due to sharing of injection equipment other than syringes. Except for transmission pairs, network distance between incident case subjects and genetic distance between their HCV variants were uncorrelated. These findings indicate that, without dramatic reductions in injection risk behaviors, shattering of cohesive injection networks, and/or broad coverage of an effective vaccine, HCV will likely remain hyperendemic in drug injectors. Brewer, D., Hagan, H., Sullivan, D., Muth, S., Hough, E., Feuerborn, N., and Gretch, D. Social Structural and Behavioral Underpinnings of Hyperendemic Hepatitis C Virus Transmission in Drug Injectors. J Infect Dis, 194(6), pp. 764-772, 2006.

Response to Overdose among Injection Drug Users

Drug overdose is a leading cause of mortality among illicit drug users. This study characterizes responses to overdose among injection drug users (IDUs) in Baltimore, Maryland, and identifies factors associated with medically inappropriate responses. A cross-sectional survey was administered to 924 IDUs in an ongoing cohort study between August 2003 and September 2004. Self-reported experiences of witnessing overdose were obtained by structured interview. Multiple logistic regression identified associations between overdose information sources and medically inappropriate responses. Most IDUs (69.7%) reported ever witnessing an overdose. The most common responses were walking the victim around (70.8%), shaking them (64.9%), and inflicting pain (62.6%). One in four (25.8%) injected the victim with salt water. Two thirds (63.4%) called 911, but more than half delayed the call by 5 or more minutes. The most common reason cited for delaying or foregoing the 911 call was the belief that they could revive the victim themselves, followed by fear of police involvement. Most IDUs had received information on how to prevent or respond to an overdose, but most (73.2%) received this information from friends or other drug users. IDUs who got overdose information solely from lay sources were less likely to call 911 (adjusted odds ratio [AOR] = 0.66, 95% confidence interval [CI] = 0.46-0.94) and more likely to inject the victim with salt water (AOR = 2.06, 95% CI = 1.36-3.13) than IDUs who received no information at all. Injection drug users who received information from medical and social services providers only were less likely to delay the 911 call (AOR = 0.35, 95% CI = 0.22-0.72). These findings indicate that inappropriate overdose responses are widespread among IDUs in Baltimore. Interventions that provide overdose education and reduce police response to overdose events are likely to improve witness responses and reduce mortality associated with drug overdose. Pollini, R., McCall, L., Mehta, S., Celentano, D., Vlahov, D., and Strathdee, S. Response to Overdose Among Injection Drug Users. Am J Prev Med, 31(3), pp. 261-264, 2006.

Diversion of Ultram and Other Tramadol Products

Ultram (tramadol HCL) was approved by the Food and Drug Administration in 1994 as a non-scheduled drug under the Controlled Substance Act. The non-scheduled status was contingent on the development and implementation of a comprehensive post-marketing surveillance program by an Independent Steering Committee external to Ortho-McNeil Pharmaceutical charged with monitoring abuse and recommending scheduling if unexpectedly high abuse occurred. The program developed by this committee was composed of a variety of studies, and the results of the first three years of the surveillance efforts revealed that the rate of Ultram abuse was low. At a meeting of the FDA in 1998 to reexamine the scheduling status of Ultram, it was recommended that the scope of the postmarketing surveillance program be broadened to include data on diversion. After a 1-year pilot study, by January 2002, a nationwide diversion survey was fully operational. This brief communication describes the experiences of this diversion study, and compares the findings on the diversion of Ultram and other tramadol HCL products with that of more widely abused drugs. Survey data suggest that the diversion of Ultram and other tramadol products is low, and overall, diversion investigators did not consider tramadol to be a problem in their respective jurisdictions. Inciardi, J., Cicero, T., Munoz, A., Adams, E., Geller, A., Senay, E., and Woody, G. The Diversion of Ultram, Ultracet, and Generic Tramadol HCL. J Addict Dis, 25(2), pp. 53-58, 2006.

Polydrug Use among Ecstasy-Using Youth

In this study, the authors estimated the prevalence of ecstasy use within a large college student sample and investigated the polydrug-use history of those ecstasy users. They administered an anonymous questionnaire to college students (N = 1,206) in classrooms at a large university in the mid-Atlantic United States. The overall student response rate was 91%. Nine percent of the sample reported lifetime ecstasy use. Because 98% of ecstasy users had used marijuana, the authors compared polydrug use between ecstasy users and individuals who had used marijuana but not ecstasy. Ecstasy users, as compared with these marijuana users, were significantly more likely to have used inhalants (38% vs. 10%), LSD (38% vs. 5%), cocaine (46% vs 2%), and heroin (17% vs 1%) in the past year. Significant polydrug use among college student ecstasy users has important implications for their substance abuse treatment. Wish, E., Fitzelle, D., O 'Grady, K., Hsu, M., and Arria, A. Evidence for Significant Polydrug Use Among Ecstasy-Using College Students. J Am Coll Health, 55(2), pp. 99-104, 2006.

The Role of Internalizing and Externalizing Behavior Problems and Peer Selection in Adolescent Substance Use

To date, research examining the role of peers in the development of substance use has focused almost exclusively on externalizing behavior problems without considering internalizing behavior problems. This is a notable omission in the literature, because there is some evidence to suggest that internalizing behavior increases risk for substance use, and peers are considered to be among the strongest proximal influences of substance use. The current study considered both internalizing and externalizing behavior problems and examined peer socialization and selection models of alcohol use using a 2-year longitudinal design. Authors examined potential reciprocal relations between internalizing and externalizing behavior and affiliations with delinquent peers, and how these variables predicted initiation of alcohol use. Participants were 86 children (71% male) ranging from 9-12 years of age (M=10.87). Results were consistent with socialization, whereby delinquent peer affiliations were associated with increases in externalizing behavior, and subsequently early initiation of alcohol use. There was also evidence to suggest that internalizing behavior served as a protective factor for delinquent peer affiliations and for early initiation of alcohol use. Implications of these findings for prevention and intervention efforts are discussed. Fite, P., Colder, C., and O 'Connor, R. Childhood Behavior Problems and Peer Selection and Socialization: Risk for Adolescent Alcohol Use. Addict Behav, 31(8), pp. 1454-1459, 2006.

Increased Access to Unrestricted Pharmacy Sales of Syringes in Seattle-King County, Washington: Structural and Individual-Level Changes, 1996 versus 2003

Researchers explored pharmacists' attitudes and practices related to syringe sales to injection drug users before and after legal reform and local programming in Seattle, Washington to enhance sterile syringe access. They replicated a 1996 study by conducting pharmacist phone surveys (with 227 of 269 eligible pharmacies, for a response rate of 85%) and syringe test-buys in 100 randomly selected pharmacies in the Seattle region and in the suburbs. Overall test-buy success increased from 48% in 1996 to 65% in 2003 (P=.04). Pharmacists agreeing that syringes should be available to injection drug users through pharmacy purchase increased over the study period from 49% to 71% (P<.01). These findings suggest that pharmacy policies and pharmacist attitudes were strongly associated with syringe access. Structural changes, including policy reform and pharmacy outreach, appear to increase syringe access. Interventions should address pharmacy policies and pharmacist attitudes and policies. Deibert, R., Goldbaum, G., Parker, T., Hagan, H., Marks, R., Hanrahan, M., and Thiede, H. Increased Access to Unrestricted Pharmacy Sales of Syringes in Seattle-King County, Washington: Structural and Individual-Level Changes, 1996 versus 2003. Am J Public Health, 96(8), pp. 1347-1353, 2006.

Changes in Canadian Heroin Supply Coinciding with the Australian Heroin Shortage

Prior research has largely attributed the Australian heroin shortage to increases in local law enforcement efforts. Because western Canada receives heroin from similar source nations, but has not measurably increased enforcement practices or funding levels, researchers in Vancouver sought to examine trends in Canadian heroin-related indices before and after the Australian heroin shortage, which began in approximately January 2001. During periods before and after January 2001, they examined the number of fatal overdoses and ambulance responses to heroin-related overdoses that required the use of naloxone in British Columbia, Canada. As an overall marker of Canadian supply reduction, they also examined the quantity of heroin seized during this period. Lastly, they examined trends in daily heroin use among IDUs enrolled in the Vancouver Injection Drug Users Study (VIDUS). They found a 35% reduction in overdose deaths, from an annual average of 297 deaths during the years 1998-2000 compared to an average of 192 deaths during 2001-03. Similarly, use of naloxone declined 45% in the period coinciding with the Australian heroin shortage. Interestingly, the weight of Canadian heroin seized declined 64% coincident to the Australian heroin shortage, from an average of 184 kg during 1998-2000 to 67 kg on average during 2001-03. Among 1587 VIDUS participants, the period coinciding with the Australian heroin shortage was associated independently with reduced daily injection of heroin [adjusted odds ratio: 0.55 (95% CI: 0.50-0.61); P < 0.001]. These findings indicate that massive decreases in 3 independent markers of heroin use observed in western Canada coincided with the Australian heroin shortage, despite little if any budgetary changes for Canadian enforcement efforts. Markedly reduced Canadian seizure activity also coincided with the Australian heroin shortage. These findings underscore the importance and credence of external global heroin supply forces as a potential explanation for the Australian heroin shortage. Wood, E., Stoltz, J., Li, K., Montaner, J., and Kerr, T. Changes in Canadian Heroin Supply Coinciding with the Australian Heroin Shortage. Addiction, 101(5), pp. 689-695, 2006.

HTLV-2 Infection in Injection Drug Users in King County, Washington

Human T-cell lymphotropic virus type 2 (HTLV-2) is endemic in injection drug users (IDU), and Native American populations in the Americas. Transmission is associated with high-risk injection and sexual practices. A cohort of 2561 IDU in King County, Washington completed 2 study visits over 1 year. HTLV-2 infection was detected in 190 (7.4%) of 2,561 IDU, and 13 (7.8 cases per 1000 person-years) incident infections occurred during the study. Prevalent infection was associated with female gender, non-white race, longer duration as IDU, having a tattoo, combined injection of heroin and cocaine, and with serologic evidence of hepatitis B and C infection. Seroconversion was more common in women, and was associated with African American race, heterosexual identity and longer duration as IDU. Increased risk of HTLV-2 infection was associated with non-white race, and injection drug of choice, suggesting injection networks may play an important role in transmission of HTLV-2. The high correlation of HTLV-2 infection with HCV infection suggests the major route of transmission in IDU is via injection practices. This study points to the need for studies on the clinical manifestations of HTLV-2 infection, as well as the clinical and virological manifestations of HTLV-2/HCV coinfection. Zunt, J., Tapia, K., Thiede, H., Lee, R., and Hagan, H. HTLV-2 Infection in Injection Drug Users in King County, Washington. Scand J Infect Dis, 38(8), pp. 654-663, 2006.

Is the Quality of the Patient-Provider Relationship Associated with Better Adherence and Health Outcomes for Patients with HIV?

Patient-centeredness, originally defined as understanding each patient as a unique person, is widely considered the standard for high-quality interpersonal care. The purpose of this cross-sectional analysis was to examine the association between patient perception of being "known as a person" and receipt of highly active antiretroviral therapy (HAART), adherence to HAART, and health outcomes among patients with HIV. The analysis included 4,694 interviews with 1,743 (mean 2.69 interviews per patient) patients with HIV. The primary measures of interest were patient reports that their HIV provider "knows me as a person" and 3 outcomes: receipt of HAART, adherence to HAART, and undetectable serum HIV RNA. Findings indicated that patients who reported that their provider knows them "as a person" were more likely to receive HAART (60% vs 47%, P<.001), be adherent to HAART (76% vs 67%, P=.007), and have undetectable serum HIV RNA (49% vs 39%, P<.001). Patients who reported their provider knows them "as a person" were also older (mean 38.0 vs 36.6 years, P<.001), reported higher quality-of-life (mean LASA score 71.1 vs 64.8, P<.001), had been followed in clinic longer (mean 64.4 vs 61.7 months, P=.008), missed fewer appointments (mean proportion missed appointments 0.124 vs 0.144, P<.001), reported more positive beliefs about HAART therapy (39% vs 28% strongly believed HIV medications could help them live longer, P<.008), reported less social stress (50% vs 62% did not eat regular meals, P<.001) and were less likely to use illicit drugs or alcohol (22% vs 33% used drugs, P<.001; 42% vs 53% used alcohol, P<.001). Controlling for patient age, sex, race/ethnicity, quality-of-life, length of time in clinic, missed appointments, health beliefs, social stress, and illicit drug and alcohol use, patients who reported their provider knows them "as a person" had higher odds of receiving HAART (odds ratio [OR] 1.41, 95% confidence interval [CI] 1.19 to 1.65), adhering to HAART (OR 1.33, 95% CI 1.02 to 1.72), and having undetectable serum HIV RNA (1.20, 95% CI 1.02 to 1.41). These findings indicate that a single item measuring the essence of patient-centeredness-i.e., the patients' perception of being "known as a person"- is significantly and independently associated with receiving HAART, adhering to HAART, and having undetectable serum HIV RNA. These results support the hypothesis that the quality of patient-physician relationship is directly related to the health of patients. Beach, M., Keruly, J., and Moore, R. Is the Quality of the Patient-Provider Relationship Associated with Better Adherence and Health Outcomes for Patients with HIV? J Gen Intern Med, 21(6), pp. 661-665, 2006.

Prevalence and Correlates of Suicidal Ideation among Young Injection vs. Noninjection Drug Users

The objective of this study was to identify correlates of suicidal ideation and to examine the hypothesis that injection drug users (IDUs) were more likely to report suicidal ideation than noninjection drug users (NIDUs). Participants included IDUs (n = 244) and NIDUs (n = 73) from Baltimore, Maryland, aged 15-30 who began snorting or smoking heroin or cocaine/crack (NIDUs) or injecting drugs (IDUs) within the past 5 years who were recruited between August 2000 and March 2002. Among the 317 participants, 42% were female, 59% were white, and median age was 24. The prevalence of suicidal ideation was 27%. IDUs were more likely to report suicidal ideation than NIDUs (31% vs. 14%, p = 0.003). Adjusting for age, gender, and race, IDUs were 2.4 times more likely than NIDUs to report suicidal ideation [95% Confidence Interval (CI): 1.1-5.2]. However, on further adjustment for homelessness, depressive symptoms, and gay/lesbian/bisexual identity, IDU status was no longer independently associated with suicidal ideation. These results suggest that factors associated with injection drug users' lifestyles and mental health status may account for the higher prevalence of suicidal ideation in IDUs vs. NIDUs. Further study into these associations is warranted in identifying avenues for suicide prevention among these populations. Havens, J., Sherman, S., Sapun, M., and Strathdee, S. Prevalence and Correlates of Suicidal Ideation among Young Injection vs. Noninjection Drug Users. Subst Use Misuse, 41(2), pp. 245-254, 2006.

Gender Differences in Sexual Behaviors, Sexual Partnerships, and HIV among Drug Users in New York City

Researchers sought to compare sexual behaviors/partnerships and sexual risk correlates associated with HIV by gender among sexually active, street-recruited drug users in New York City. The study sample included 818 men and women (average age 28 vs 30 years, p<.01). Men were more likely to be Latino (63% vs 41%, p<.01), recently homeless (61% vs 50%, p<.01) or previously incarcerated (90% vs 79%, p<.01) compared to women. More men than women reported being an IDU (29% vs 20%, p<.01). Among non-IDUs, men were less likely to report crack use, more likely to report marijuana use, and use of hallucinogens. Men reported higher risk sexual behaviors, yet fewer high-risk sexual partners than women. After adjustment, HIV seropositive men were more likely than seronegatives to be older, MSM, use condoms, and have an HIV-infected partner. HIV seropositive women were more likely to be older, have an HIV-infected partner, and not use non-injected heroin. IDU was not associated with HIV. These findings highlight the need to determine how gender-specific sexual behaviors/partnerships among drug users affect HIV acquisition. Absalon, J., Fuller, C.M., Ompad, D.C., Blaney, S., Koblin, B., Galea, S., and Vlahov, D. Gender Differences in Sexual Behaviors, Sexual Partnerships, and HIV Among Drug Users in New York City. AIDS Behav, 10(6), pp. 707-715, 2006.

Service Uptake and Characteristics of Injection Drug Users Utilizing North America's First Medically Supervised Safer Injecting Facility

In 2003, the city of Vancouver, British Columbia, opened North America's first government-sanctioned safer injecting facility, where injection drug users (IDUs) can inject preobtained illicit drugs under the supervision of nurses between 10:00 AM to 4:00 AM. Of 713 IDUs who enrolled to use the facility, 308 (43.2%) reported using it daily at the first interview. The average number of daily visits in the first week of operation was 200; the average increased to 500 visits a day and has remained at that level since. Substances used include heroin (42%), cocaine (32%), and other substances (26%). Use of the service by IDUs was followed by measurable reductions in public drug use and syringe sharing. IDUs who are frequently using the program are significantly more likely to be high-intensity (daily) cocaine and heroin injectors, younger than non-daily users (38 yrs vs 40 yrs, p<.001), and homeless. Among the daily users, 88% tested HCV-positive and 16% tested HIV. The facility has provided high-risk IDUs a hygienic space where syringe sharing can be eliminated and the risk of fatal overdose reduced. Ongoing evaluation will be required to assess its impact on overdose rates and HIV infection levels, as well as its ability to improve IDU contact with medical care and addiction treatment. Wood, E., Tyndall, M., Qui, Z., Zhang, R., Montaner, J., and Kerr, T. Service Uptake and Characteristics of Injection Drug Users Utilizing North America 's First Medically Supervised Safer Injecting Facility. Am J Public Health, 96(5), pp. 770-773, 2006.

Nonadherence to Antiretroviral Therapy among a Community with Endemic Rates of Injection Drug Use

Highly active antiretroviral therapy (HAART) has resulted in major reductions in HIV-related morbidity and mortality. However, long-term use of HAART is challenging, and substantial numbers of patients discontinue their medications prematurely. The purpose of this analysis is to describe HAART adherence rates among a large urban cohort (N=2985) and examine factors associated with adherence (based on refill compliance). Of the 184 eligible participants on HAART, 129 (70%) were less than 95% adherent. Variables independently associated with nonadherence included frequent heroin injection (adjusted odds ratio [AOR] = 2.6, 95% confidence interval [CI], 1.6-4.0), baseline CD4 count less than 200 cells/mm (3) (AOR = 2.5; 95% CI, 1.9-3.2), and poor treatment by health care professionals (AOR = 1.7; 95% CI, 1.2-3.0). Variables inversely associated with HAART nonadherence included attaining viral load suppression (AOR = 0.3; 95% CI, 0.2-0.5) and methadone maintenance therapy (AOR = 0.5; 95% CI, 0.4-0.9). These findings suggest that innovative strategies that address the social barriers facing marginalized populations are needed to support the long-term continuation of HAART. Shannon, K., Kerr, T., Lai, C., Ishida, T., Wood, E., Montaner, J., Hogg, R., and Tyndall, M. Nonadherence to Antiretroviral Therapy Among a Community with Endemic Rates of Injection Drug Use. J Int Assoc Physicians AIDS Care (Chic Ill), 4(3), pp. 66-72, 2005.

Differences in Access to Care among Injection Drug Users Infected Either with HIV and Hepatitis C or Hepatitis C Alone

Access to HCV (Hepatitis C virus) care for HIV/HCV-co-infected patients is an urgent public health concern. The objective of this study was to describe the self-reported health status of HIV/HCV-co-infected and HCV-mono-infected IDUs and to describe their access to HCV-related care. Beginning in May 1996, persons who had injected illicit drugs in the previous month were recruited into an open cohort study called the Vancouver Injection Drug User Study (VIDUS). At baseline and then semi-annually, participants complete an interviewer-administered questionnaire. Blood is drawn at each semi-annual interview and tested for HIV and Hepatitis C infection. Data for this descriptive, cross-sectional analysis were drawn from the most recent of either the July 2003 or December 2003 nurse-administered questionnaire. Statistics used were the chi-square, Wilcoxon Rank Sum and Student's t-test. Logistic regression was used to examine factors independently associated with accessing HCV care. There were 707 IDUs eligible for this analysis, including 240 HIV/HCV-co-infected and 467 HCV-mono-infected persons. Co-infected individuals were more likely to be female, younger, of Aboriginal ethnicity and less likely to use heroin daily. The HCV-mono-infected group tended to report higher rates of HCV-related symptoms, including fatigue, liver pain, nausea, night-sweats and stomach pain. However, it was the HIV/HCV-co-infected group who were more likely to report that they believed their HCV was affecting them. The HIV/HCV-co-infected group were also more likely to report having received any hepatitis-related follow-up care, including blood work, liver biopsies and referrals to specialists. In logistic regression analysis, factors independently associated with ever receiving any HCV-related follow-up were HIV/HCV-co-infection (AOR 3.1; 95% CI: 2-4.7), being older (AOR 1.04; 95% CI: 1.02-1.06 per year older), using heroin daily (AOR 0.54; 95% CI: 0.36-0.82) and believing that hepatitis C was affecting one's health (AOR 1.4; 95% CI: 1.0-2.1). These findings suggest that HCV healthcare utilization is greater among those who are HIV/HCV-co-infected, and that this group is experiencing more morbidity compared to the HCV mono-infected. Braitstein, P., Li, K., Kerr, T., Montaner, J., Hogg, R., and Wood, E. Differences in Access to Care among Injection Drug Users Infected Either with HIV and Hepatitis C or Hepatitis C Alone. AIDS Care, 18(7), pp. 690-693, 2006.

Needle Exchange Use, Sexual Risk Behaviour, and the Prevalence of HIV, Hepatitis B Virus, and Hepatitis C Virus Infections among Bulgarian Injection Drug Users

At a time when the rates of HIV, hepatitis C virus (HCV), and hepatitis B virus (HBV) infections have risen among injection drug users (IDUs) in other countries in the region, little is known about the prevalence of these infections among Bulgarian injectors, nor about their sexual risk behaviours. Geographically, Bulgaria is situated on the major trafficking routes of illegal drugs from the Middle East to Central and Western Europe. Large amounts of heroin enter Bulgaria through its border with Turkey; this, coupled with the fall of communism, has been linked to the country's first epidemic of heroin use in the early 1990s. This study supported by a NIDA international supplement, involved structured interviews with IDUs (n = 773) in a community-based needle exchange programme (NEP) and two major drug treatment facilities in Sofia, Bulgaria, as well as testing for HIV, HBV, and HCV antibodies. The mean age in the sample was 26 years, with 79% male, 84% Bulgarian, and 13% Roma. While HCV prevalence in the sample was 73.9%, HBV and HIV prevalence was low -6% and 0.5%, respectively. Having more than 10 sexual partners, having sex with someone with hepatitis C or another IDU, and never using a condom with another IDU were common among those who were recruited through the NEP. Given that 40% of the IDUs reported using the NEP, the study indicates that needle exchange provides an important opportunity to reach high-risk populations and prevent the drug use- and sexually-related transmission of HIV and other blood-borne pathogens. Vassilev, Z., Hagan, H., Lyubenova, A., Tomov, N., Vasilev, G., Krasteva, D., and Des Jarlais, D. Needle Exchange Use, Sexual Risk Behaviour, and the Prevalence of HIV, Hepatitis B Virus, and Hepatitis C Virus Infections Among Bulgarian Injection Drug Users. Int J STD AIDS, 17(9), pp. 621-626, 2006.

Progression of Liver Fibrosis among Injection Drug Users with Chronic Hepatitis C

Although most hepatitis C virus (HCV) infections are acquired by injection drug use, prospective data on the progression of liver fibrosis are sparse. For this study, baseline liver biopsies were obtained (1996-1998) on a random sample of 210 out of 1667 HCV-positive injection drug users (IDUs). Subjects were followed biannually, with a second biopsy offered to those eligible. Paired biopsies were scored 0 to 6 (modified Ishak score), significant fibrosis was defined as score 3 or greater, and progression of fibrosis was defined as an increase 2 or more units or clinical evidence of end-stage liver disease. Predictive values of blood markers [FibroSURE, aspartate aminotransferase-to-platelet-ratio index (APRI) and alanine aminotransferase (ALT)] were assessed for detection of contemporaneous and future liver fibrosis. Among 119 prospectively followed IDUs, 96% were African American; 97% HCV genotype 1a/b; 27% HIV-infected, and median age was 42 years. Most (90.7%) did not have significant liver fibrosis at first biopsy. Although predictive value for detecting insignificant fibrosis at first biopsy was greater than 95% for FibroSURE, APRI, and ALT, specificities were 88.9%, 72.7%, and 72.7%, respectively. After 4.2 years median follow-up, 21% had progression of fibrosis, which was significantly associated with serum level of HCV RNA and ALT. No serological test had predictive value greater than 40% for contemporaneous or future significant fibrosis. Even initial biopsy result had only a 30.4% value for predicting future significant fibrosis. Significant liver fibrosis and progression were detected in some, but not most, IDUs in this cohort, indicating that in this setting of low fibrosis prevalence, FibroSURE, ALT, and APRI tests predict insignificant fibrosis, and that further work is needed to find noninvasive markers of significant liver fibrosis. Wilson, L., Torbenson, M., Astemborski, J., Faruki, H., Spoler, C., Rai, R., Mehta, S., Kirk, G., Nelson, K., Afdhal, N., and Thomas, D. Progression of Liver Fibrosis among Injection Drug Users with Chronic Hepatitis C. Hepatology, 43(4), pp. 788-795, 2006.

A Comparison of Salivary Cotinine Concentrations with Self-Reported Cigarette Smoking in Adolescence

The authors examined the extent and sources of discrepancies between self-reported cigarette smoking and salivary cotinine concentration among adolescents. Household interviews with a cohort of 1,024 adolescents from an urban school system, histories of tobacco use in the last 7 days, and saliva samples were obtained. Logistic regressions identified correlates of three inconsistent patterns: (a) Pattern 1-self-reported nonsmoking among adolescents with high cotinine concentration, (b) Pattern 2-low cotinine concentration among adolescents reporting having smoked within the last 3 days, and (c) Pattern 3-high cotinine concentration among adolescents reporting not having smoked within the last 3 days. Rates of inconsistency were high among smokers defined by cotinine levels or self-reports (Pattern 1 = 49.1%; Pattern 2 = 42.0%). Controlling for other covariates, the authors found that reports of nonsmoking among those with high cotinine (Pattern 1) were associated with younger age, having few friends smoking, little recent exposure to smokers, and being interviewed by the same interviewer as the parent and on the same day. Low cotinine concentration among self-reported smokers (Pattern 2) was negatively associated with older age, being African American, number of cigarettes smoked, depth of inhalation, and exposure to passive smoke but positively associated with less recent smoking and depressive symptoms. High cotinine concentrations among self-reported nonsmokers was positively associated with exposure to passive smoke (Pattern 3). The authors report that the data are consonant with laboratory findings regarding ethnic differences in nicotine metabolism rate. The inverse relationship of cotinine concentration with depressive symptoms has not previously been reported. The authors suggest that depressed adolescent smokers may take in smaller doses of nicotine than nondepressed smokers; alternatively, depressed adolescents may metabolize nicotine more rapidly. Kandel, D., Schaffran, C., Griesler, P., Hu, M., Davies, M., and Benowitz, N. Salivary Cotinine Concentration Versus Self-Reported Cigarette Smoking: Three patterns of inconsistency in adolescence. Nicotine Tob Res, 8(4), pp. 525-537, 2006.

The Impact of Drug Use on Perceptions of Credibility in Indigenous Outreach Workers

This study examined perceptions of outreach worker credibility (i.e., expertise and trustworthiness) by the respective social network members (N = 20) of indigenous outreach workers in an HIV/AIDS prevention intervention. Most evaluations of outreach-based programs have focused on how and where a message is being conveyed rather than on the relationship between the speaker and listener, and have overlooked how a speaker's past or current drug use may affect his or her credibility as a messenger of behavioral change. The network members in this study participated in semistructured interviews following the program's completion. Outreach workers who were not actively using illicit drugs were more likely to be described as credible than were those who were using drugs. In general, drug use negatively affected perceptions of credibility via damaged trust in the outreach worker's relationship with his or her network member. These findings indicate the complexity of using indigenous drug users as outreach workers, the potential negative perceptions concerning hypocritical behavior, and the need to evaluate social interventions from the standpoint of indirect participants. Mitchell, S., Peterson, J., and Latkin, C. The Impact of Drug Use on Perceptions of Credibility in Indigenous Outreach Workers. Qual Health Res, 16(8), pp. 1108-1119, 2006.

Heritability of Drug Use and Dependence among Norwegian Twins

Prior population-based twin studies of drug abuse have taken place in two countries with similar cultures and high rates of drug abuse, namely the USA and Australia. In this study, the authors estimated genetic and environmental contributions to drug abuse in a sample from Norway, a Nordic country with a low prevalence of illicit drug use. Lifetime use, abuse and dependence of five illicit drug categories (cannabis, stimulants, opiates, cocaine and psychedelics) were assessed at personal interview in 1386 complete young adult twin pairs (ages 20-32) ascertained from the Norwegian Institute of Public Health Twin Panel. Twin model fitting was performed using the Mx statistical package on three phenotypes: any lifetime use, endorsement of at least one DSM-IV symptom of abuse or dependence, and meeting DSM-IV criteria for abuse or dependence. As expected, significant lifetime use of illicit substances (defined as use 10 or more times) was reported by only 6.4% of the sample. Meaningful analyses were possible for use of any substance and each of the five substances individually, but for symptoms or a diagnosis of abuse/dependence meaningful analyses were possible only for any substance and cannabis. Full twin models uniformly found twin resemblance to be due largely or entirely to genetic factors. Best-fit models for all analyses included only genetic and individual-specific environmental effects with heritability estimates ranging from 58% to 81%. In accord with prior results from the USA and Australia, genetic factors appear to play an important role in the etiology of use and abuse/dependence of illicit drugs in Norway. Thus, these findings suggest that heritabilty is not affected by drug availability; however, further work is needed. Kendler, K., Aggen, S., Tambs, K., and Reichborn-Kjennerud, T. Illicit Psychoactive Substance Use, Abuse and Dependence in a Population-based Sample of Norwegian Twins. Psychol Med, 36(7), pp. 955-962, 2006.

Substance Abuse and Psychiatric Disorders in HIV-positive Patients: Epidemiology and Impact on Antiretroviral Therapy

There is a high prevalence of substance abuse and psychiatric disorders among HIV-infected individuals. Importantly, drug and alcohol-use disorders are frequently co-morbid with depression, anxiety, and severe mental illness. Not only do these disorders increase the risk of contracting HIV, they have also been associated with decreased highly active antiretroviral therapy (HAART) utilization, adherence and virological suppression. The literature evaluating the relationship between substance abuse and HIV outcomes has primarily focused on injection drug users, although there has been increasing interest in alcohol, cocaine and marijuana. Similarly, the mental health literature has focused largely on depression, with a lesser focus on severe mental illness or anxiety. To date, there is little literature evaluating the association between co-occurring HIV, substance abuse and mental illness on HAART uptake, adherence and virological suppression. Adherence interventions in these populations have demonstrated mixed efficacy. Both directly observed therapy and pharmacist-assisted interventions appear promising, as do integrated behavioural interventions. However, the current intervention literature has several limitations: few of these studies are randomized, controlled trials; the sample sizes have generally been small; and co-occurring substance abuse and mental illness has not specifically been targeted in these studies. Future studies examining individual substances of abuse, psychiatric disorders and co-occurring substance abuse and psychiatric disorders on HIV outcomes will inform targeted adherence interventions. Chander, G., Himelhoch, S., and Moore, R. Substance Abuse and Psychiatric Disorders in HIV-positive Patients: Epidemiology and Impact on Antiretroviral Therapy. Drugs, 66(6), pp. 769-789, 2006.

Substance Use and Problem Behavior across Three Generations

This study examined patterns of between-generation continuity in substance use from generation 1 (G1) parents to generation 2 (G2) adolescents and from G2 adult substance use and G1 substance use to generation 3 (G3) problem behavior in childhood. Structural equation modeling of prospective, longitudinal data from 808 participants, their parents, and their children showed low levels of G1 to G2 cross-generational continuity in the general tendency to use drugs. This effect was fully mediated by G2 early adolescent behavior problems. Drug-specific residual effects were observed across generations for cigarette smoking. Once established in adolescence, substance use in G2 showed stability over time. G2 substance use at age 27 significantly predicted G3 problem behavior. G1 substance use also was related to G3 problem behavior indirectly. These findings highlight the importance of interrupting intergenerational cycles of substance use and problem behavior. Bailey, J., Hill, K., Oesterle, S., and Hawkins, J. Linking Substance Use and Problem Behavior Across Three Generations. J Abnorm Child Psychol, 34(3), pp. 263-292, 2006.

Exposure to Family Violence and Childhood Bullying

The objectives of this study were to describe the prevalence of bullying involvement (ie, bullying and victimization) among children from a multigenerational study and to examine the relationship of these childhood behaviors and exposure to intimate partner violence. A community-based cohort of 112 children (aged 6 to 13 years) was asked to self-report on physical, verbal, and relational types of bullying and victimization experienced in the past year. Parents reported on their child's externalizing and internalizing behaviors during the previous 6 months using items from Achenbach's Child Behavior Checklist. The frequency of parental experiences of intimate partner violence perpetration and victimization at 2 time points during the preceding 5 years was measured using Conflict Tactics Scale items. The association of intimate partner violence and parent-reported child behavioral problems was examined, followed by exposure to intimate partner violence and child-reported bullying or victimization. Parental risk factors (eg, race/ethnicity, education, problem drinking) that predispose to intimate partner violence were controlled for using propensity score statistical modeling. Eighty-two (73.2%) children reported being victimized by peers, and 38 (33.9%) children reported bullying behaviors in the past year. More reports came from girls than from boys (55% for victimization and 61% for bullying). Almost all (97%) child bullies were also victims themselves. Intimate partner violence was reported by parent respondents in 53 (50.5%) households at any or both of the 2 time points. Exposure to intimate partner violence was not associated with child-reported relational bullying behaviors or victimization by peers, however, intimate partner violence-exposed children were at increased risk for problematic levels of externalizing behavior/physical aggression and internalizing behaviors. In this sample, children who were 6 to 13 years of age reported a substantial amount of bullying and victimization; a large majority were bully-victims and female. Regression analyses did not show that children who were exposed to intimate partner violence were more likely to engage in relational bullying. However, children who are exposed to intimate partner violence have a higher likelihood of internalizing behaviors and physical aggression. Bauer, N., Herrenkohl, T., Lozano, P., Rivara, F., Hill, K., and Hawkins, J. Childhood Bullying Involvement and Exposure To Intimate Partner Violence. Pediatrics, 118(2), pp. e235-e242, 2006.

Neglect and Later Externalizing Problems in Children of Adolescent Mothers

The present study examines the role of neglect potential in adolescent mother-child dyads, both in terms of antecedents and its consequences for children's development. Participants were 100 adolescent mother-child dyads who were part of a larger, longitudinal study. Data were collected from the third trimester of pregnancy until the children's 10th year. Histories of maternal neglect and the quality of mother-child interactions during early childhood were found to predict neglect potential during middle childhood. Mothers with high neglect potential had children who exhibited more externalizing problems and fewer adaptive behaviors, with neglect potential mediating the effects of both early abuse potential and the quality of parenting on children's later externalizing behaviors. Results suggest that neglect potential may be a mechanism through which early potential for child abuse and insensitive maternal interactions affect later externalizing problems in children of adolescent mothers. Lounds, J., Borkowski, J., and Whitman, T. The Potential for Child Neglect: The Case of Adolescent Mothers and their Children. Child Maltreat, 11(3), pp. 281-294, 2006.

Aggressive Behaviors in Adolescents of HIV-positive and HIV-negative Drug Abusing Fathers

This study examined aggressive behaviors in the adolescent children of HIV-positive and HIV-negative drug-abusing fathers. Data were collected via individual structured interviews of low-income, predominantly African American and Hispanic, father-child dyads (N = 415). Structural Equation Modeling was used to assess the interrelationship of several latent constructs with respect to adolescent aggression. Results showed a mediational model linking paternal attributes (including HIV status) and ecological factors with the father-child relationship, which impacted peer influences and the adolescent's vulnerable personality, which was the most proximal construct to aggressive behaviors. Ecological factors were also mediated by peer influences and directly linked with adolescent aggression. Brook, D., Brook, J., Rubenstone, E., and Zhang, C. Aggressive Behaviors in the Adolescent Children of HIV-positive and HIV-Negative Drug-Abusing Fathers. Am J Drug Alcohol Abuse, 32(3), pp. 399-413, 2006.

Barriers and Pathways to Diffusion of Methamphetamine Use Among African Americans in the Rural South: Preliminary Ethnographic Findings

There are no known studies of African American use of methamphetamine in the rural South, where it has been found to be widespread among whites. This qualitative ethnographic study was conducted to identify factors that may inhibit or facilitate the diffusion of methamphetamine use among African Americans living in rural Arkansas and Kentucky. Qualitative interviews were conducted with 86 stimulant users, 45 in rural Arkansas and 41in Kentucky. There were 51 whites, 34 African Americans, and one multiethnic participant. Among the 34 African Americans, 14 reported prior methamphetamine use, but only one reported being a current user. By contrast, 31 of the 51 whites or about 61% reported current methamphetamine use. These findings suggest that there is comparatively low prevalence of methamphetamine use among African Americans in the rural South. Interviewees cited several barriers to its diffusion, including the drug's ingredients, its psychoactive and physiological effects, and the difficulty of accessing distribution networks. They also described a preference among African-Americans for cocaine, attributed in part to its quicker onset of psychoactive effects. The authors caution that more research is needed to understand African American's low use of methamphetamine. They also note that multicultural connections among whites and African Americans are increasing and are likely to change barriers and pathways to diffusion of methamphetamine use among African Americans in years to come. Sexton, R., Carlson, R., Siegal, H., Falck, R., Leukefeld, C., and Booth, B. Barriers and Pathways to Diffusion of Methamphetamine Use Among African Americans in the Rural South: Preliminary Ethnographic Findings. J Ethn Subst Abuse, 4(1), pp. 77-103, 2005.

Sexual Identity Formation and AIDS Prevention: An Exploratory Study of Non-Gay-Identified Puerto Rican MSM from Working Class Neighborhood

As a subgroup of men who have sex with men (MSM), non-gay-identified (NGI) behaviorally bisexual Latino MSM are associated with heightened probabilities of HIV transmission, yet they have eluded HIV/AIDS interventionists. This exploratory study among 20 Puerto Rican MSM heroin-dependent injection drug users (average age 25 years) employed multi-session qualitative interviews to examine early life experiences related to gender identity and sexual orientation, and the place of risky drug and sexual behaviors in the process of sexual identity formation. NGI participants (n=8) experienced sexual debut between ages 13 and 20, and most were recruited to prostitution as young teens by NGI age mates who were also members of drug use networks. Participants emphasized their role as insertive sexual partners and that they maintained relationships with "pasivo" biological males. This exploratory study found that it is feasible to recruit NGI MSM through primary male sexual partners and drug use networks. HIV/AIDS prevention based on an awareness of developmental histories holds promise for intervening before NGI youth reach the point of engaging in male prostitution or injection drug use. Finlinson, H., Colon, H., Robles, R., and Soto, M. Sexual Identity Formation and AIDS Prevention: An Exploratory Study of Non-Gay-Identified Puerto Rican MSM from Working Class Neighborhoods. AIDS Behav, 10(5), pp. 531-539, 2006.

An Exploratory Qualitative Study of Polydrug Use Histories among Recently Initiated Injection Drug Users in San Juan, Puerto Rico

It has been shown that drug users often modulate the effects of their primary drugs of use (e.g., cocaine) by using other drugs (e.g., alcohol), yet the effect of modulating and primary drug interactions on transitions from one class of drugs to another and from noninjected drugs to injected drugs is not clear. This issue is critical for understanding polydrug abuse. Investigators conducted formative research based on in-depth qualitative interviews during 2003-2004 with 25 recently initiated drug injectors (ages 18 to 35; average 23.6 years; 84% male) residing in San Juan, Puerto Rico. Involvement in the criminal justice system was extensive (79%) and 71% currently lived with a parent or grandparent. Increased use of a primary drug (e.g., cocaine) was found to be influenced by a succession of enhancing or attenuating drugs, which participants viewed as progressively more dangerous. Use in a particular order (e.g., alcohol, heroin) seemed to reflect effectiveness in modulating primary drugs at different use intensities, as well as by the users' perceptions of the relative dangers of different drugs. Neither availability nor access appeared to affect the order in which participants used modulating drugs. Finlinson, H., Colon, H., Robles, R., and Soto-Lopez, M. An Exploratory Qualitative Study of Polydrug Use Histories among Recently Initiated Injection Drug Users in San Juan, Puerto Rico. Subst Use Misuse, 41(6-7), pp. 915-935, 2006.

Cross-National Differences in Drugs and Violence among Adolescents: Preliminary Findings of the DAVI Study

This study examined cross-national differences in drug use and violence among three sites that vary in social and political culture and drug use policies-Philadelphia, Toronto, and Amsterdam. The DAVI (Drugs, Alcohol and Violence International) study is based on personal interviews with 120 adolescents aged 14 to 17 years from three sites and two samples of 550 detainees and 570 dropouts, respectively. Seven drug use outcomes and three violence outcomes were compared across sites. The study found that site differences were dominant: only two of 10 outcomes (cannabis onset and relative drug-related violence) were not significantly related to site as a main effect or through an interaction. The most common site differences showed that the Toronto samples reported higher rates of drug use than Philadelphia and Amsterdam. The findings indicate that drug taking behavior transcends geopolitical boundaries. Moreover, rates of drug use among the disparate sites do not appear related to policy climate. Adlaf, E. M., Korf, D. J., Harrison, L., and Erickson, P. Cross-National Differences in Drugs and Violence among Adolescents: Preliminary Findings of the DAVI Study. J Drug Issues, 36(3), pp. 597-617, 2006.

Extracurricular Activities and Drug Use Among Affluent Youth

It has been suggested that over-scheduling of upper-class youth might underlie the high distress and substance use documented among them. This assumption was tested by considering suburban 8th graders' (n=314) involvement in different activities along with their perceptions of parental attitudes toward achievement. Results indicated negligible evidence for deleterious effects of high extracurricular involvement per se. Far more strongly implicated was perceived parent criticism for both girls and boys as well as the absence of after-school supervision. Low parent expectations connoted significant vulnerability especially for boys. The findings indicate that at least among early adolescents, converging scientific and media reports may have scapegoated extracurricular involvements, to some degree, as an index of ubiquitous achievement pressures in affluent communities. Luthar, S., Shoum, K., and Brown, P. Extracurricular Involvement Among Affluent Youth: A Scapegoat for "Ubiquitous Achievement Pressures"? Dev Psychol, 42(3), pp. 583-597, 2006.

A Factor Analytic Approach to Measuring Dimensions of Proactive and Reactive Aggression

This study used a confirmatory factor model to distinguish pure and co-occurring dimensions of proactive and reactive aggression, and examined the relation between parenting variables and these dimensions of aggression in a sample of 100 children (9 to 12 years of age; 69 boys). Confirmatory factor analysis (CFA) supported 3 dimensions of proactive and reactive aggression: pure proactive, pure reactive, and their co-occurrence. Parenting variables differentially related to the pure and co-occurring dimensions of aggression. Findings indicate that CFA provides a promising approach for conceptualizing aggression on a continuum and allows researchers to distinguish pure and co-occurring dimensions of proactive and reactive aggression. Fite, P., Colder, C., and Pelham, W. A Factor Analytic Approach to Distinguish Pure and Co-occurring Dimensions of Proactive and Reactive Aggression. J Clin Child Adolesc Psychol, 35(4), pp. 578-582, 2006.