Highlights of recently published NIDA-supported studies

First-time Patients Opt for Office-Based Buprenorphine

Patients starting buprenorphine treatment in a New Haven, Connecticut primary care clinic (PCC) are more likely to be new to treatment than those beginning methadone at an opioid treatment program (OTP), report Dr. Lynn Sullivan and colleagues at Yale University School of Medicine. The findings suggest that compared with methadone, office-based buprenorphine treatment attracts individuals who have less extensive addiction histories, are relatively healthier, and have more socioeconomic resources.

The investigators compared 96 patients entering a clinical trial of buprenorphine/ naloxone in a PCC with 94 participants entering a local OTP. Fifty-four percent of PCC patients were new to treatment, compared with 39 percent of those in the OTP. Among PCC patients, treatment novices were younger and more likely to be White than peers with prior methadone treatment. PCC patients reported fewer years of opioid addiction (10 versus 15, on average), lower rates of injection drug use (44 versus 60 percent), and less hepatitis C (25 versus 61 percent).

Three-fourths of PCC patients versus half of OTP participants were male, and more PCC patients were employed full-time (46 versus 15 percent). Consistent with prior research, methadone history did not affect treatment retention or abstinence rates attained with buprenorphine.
Drug and Alcohol Dependence 79(1):113-116, 2005.

Ethnicity Influences Early Smoking and Progression to Drug Abuse

African-Americans are less likely than European-Americans and Latinos to begin smoking in early adolescence or report dependence on illicit drugs during young adulthood. In a 10-year study, Dr. William Vega at the University of Medicine and Dentistry of New Jersey and Dr. Andres Gil at Florida International University monitored smoking and progression to other drug abuse in 1,208 students, starting at age 11 and ending at age 20. Among participants who began smoking in early adolescence, African-Americans were least likely to report that they still smoked or that they abused or were dependent on illicit drugs as young adults. European-Americans were most likely to still be smoking as 20-year-olds, and U.S.-born Latinos most likely to report abuse or dependence on drugs other than marijuana. These relationships held when the researchers factored in the influences of gender, socioeconomic status, education, parental smoking, and early alcohol use.
Addiction 100(9):1358-1369, 2005.

Stress Response May Underlie African- Americans' Reduced Pain Tolerance

Recent NIDA-funded research suggests a physiological difference as the explanation for African-Americans' reported low tolerance for pain. Dr. Susan Girdler and colleagues at the University of North Carolina at Chapel Hill monitored the stress responses of 51 African-American and 55 other participants, mostly Caucasians, while subjecting them to three different types of painful stimuli—ischemic, heat, and cold. The results suggest that blood pressure rises and physiological stress responses helped to offset pain sensations among the non-African-Americans, but not the African-Americans. For example, among the non-African-Americans, greater stress-induced increases in blood pressure and release of norepinephrine correlated with more tolerance to subsequent pain. No such relationship was seen among African-Americans, who exhibited less marked blood pressure rises and relatively low levels of the stress hormones.
Psychosomatic Medicine 67(6):948-956, 2005.

Methylphenidate for Comorbid Cocaine Abuse, ADHD

In an inpatient study with 14 non-treatment-seeking volunteers, Columbia University researcher Dr. Stephanie Collins and colleagues reported that a regimen of 40-60 mg/day of sustained-release methylphenidate (SR-MPH) reduced ratings on scales of "feel high," "good drug effect," and other measures of cocaine's reinforcing effects among seven abusers affected by attention deficit hyperactivity disorder (ADHD). The medication increased the cardiovascular effects seen with cocaine alone, but not to dangerous levels. Although preliminary, the findings suggest that a therapeutic approach of using slow-acting stimulants to reduce craving for cocaine—parallel to the use of methadone or buprenorphine in opiate addiction—may be possible for cocaine-addicted patients with ADHD. Although the researchers did not formally assess SR-MPH's effects on participants' ADHD symptoms, they did not note any obvious benefits.
Drug and Alcohol Dependence 82(2):158-167, 2006.

Volume 21, Number 1 (October 2006)