Recommendation Statement
U.S. Preventive Services Task Force (USPSTF)
- The U.S. Preventive Services Task
Force (USPSTF) makes recommendations about preventive care services for
patients without recognized signs or symptoms of the target condition.
- It bases its recommendations on a
systematic review of the evidence of the benefits and harms and an assessment
of the net benefit of the service.
- The USPSTF recognizes that
clinical or policy decisions involve more considerations than this body of
evidence alone. Clinicians and policymakers should understand the evidence
but individualize decisionmaking to the specific patient or situation.
Select for copyright information.
Contents
Summary of Recommendations and Evidence
Clinical Considerations
Other Considerations
Discussion
Recommendations of Others
References
Members of the USPSTF
Summary of Recommendations and Evidence
- The USPSTF concludes that the
current evidence is insufficient to assess the balance of benefits and harms of
screening adolescents, adults, and pregnant women for illicit drug use. (This is a grade "I" statement)
|
Go to
Table 1 for a description of the USPSTF grades and Table 2 for a description of
the USPSTF classification of levels of certainty regarding net benefit.
Rationale:
Importance: Illicit drug use and abuse are serious problems
among adolescents, adults, and pregnant women in the United States, ranking
among the 10 leading preventable risk factors for years of healthy life lost to
death and disability in developed countries. (Please note that tobacco use and
alcohol misuse are considered in separate screening recommendations of the
USPSTF.)
Detection: While standardized questionnaires to screen
adolescents and adults for drug use/misuse have been shown to be valid and
reliable, there is insufficient evidence to assess the clinical utility of
these instruments when applied widely in primary care settings.
Benefits of detection and
early treatment: There is good
evidence that various treatments are effective in reducing illicit drug use in
the short term. Evidence is insufficient, however, either to demonstrate that
treatment reliably improves social and legal outcomes for patients, or to link
treatment directly to longer term improvements in morbidity or mortality. Since
all but one published clinical trial of treatment interventions involved
individuals who had already developed problems due to their drug use, it is not
known whether the findings are generalizable to asymptomatic individuals whose illicit
drug use is detected through screening. There is fair evidence that, regardless
of the patient's history of treatment, reducing or stopping drug use is
associated with improvement in some health outcomes.
Harms of detection and
early treatment: There is little
evidence of harms associated with either screening for illicit drug use or behavioral
interventions used in treatment. Several clinical trials of pharmacotherapy for
drug misuse have reported mild to serious adverse events, although some of these
events were likely related to underlying drug use. The specific adverse events
noted to occur more frequently in the treatment arm of trials (compared to
placebo) have been previously recognized as potential side effects of the
treatment medication and cited on its product label.
USPSTF assessment: The USPSTF concludes that for adolescents, adults,
and pregnant women, the evidence is insufficient to determine the benefits and
harms of screening for illicit drug use.
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Clinical Considerations
Patient Population under Consideration
While the rate of illicit drug use
in the U.S. is highest between the ages of 18 to 20 years, more than 10% of
adolescents aged 12 to17 are known to use illicit drugs. The percentage of adults
who regularly use illicit drugs decreases steadily with age. About 5% of
pregnant women report using illicit drugs within the past month.
Patterns of Drug Use
Marijuana is the most commonly used illicit drug in
the United States, with about 6% of the population age 12 and older admitting
to use within the past month. While cocaine is the second most commonly used illicit
drug, it is used by less than 1% of the population. Only a small minority of
Americans use hallucinogens, inhalants, heroin, or illicitly manufactured
methamphetamine, although the potential for abuse of or dependence on these
substances is high. Illicit (non-medical) use of prescription-type drugs,
categorized as pain relievers, tranquilizers, stimulants, and sedatives, is a
growing health problem in the U.S.
Screening Tests
While clinicians should be alert to the signs and
symptoms of illicit drug use in patients, the added benefit of screening
asymptomatic patients in primary care practice remains unclear. Toxicologic
tests of blood or urine can provide objective evidence of drug use, but such
tests do not distinguish between occasional users and those who are impaired by
drug use. A few brief, standardized questionnaires have been shown to be valid
and reliable in screening adolescent and adult patients for drug use/misuse. However,
the clinical utility of these questionnaires is uncertain. The reported positive
predictive values are variable and at best 83% when the questionnaires are
applied in a general medical clinic. Moreover, the feasibility of routinely
incorporating the questionnaires into busy primary care practices has yet to be
assessed. The validity, reliability, and clinical utility of standardized
questionnaires in screening for illicit drug use during pregnancy have not been
adequately evaluated.
Treatment
Although drug-specific pharmacotherapy (e.g.,
buprenorphine for opiate abuse) and/or behavioral interventions (e.g., brief
motivational counseling for cannabis misuse) have been proven effective in reducing
illicit drug use in the short term, the longer-term effects of treatment on
morbidity and mortality have been inadequately evaluated. Moreover, these
treatments have been studied almost exclusively in individuals who have already
developed medical, social, or legal problems due to drug use, and their effectiveness
in individuals identified through screening remains unclear. In all but one
trial, treatment was delivered outside the primary care setting, often in
specialized treatment facilities. More evidence is needed on the effectiveness
of office-based treatments for illicit drug use/dependence.
Other Approaches to Prevention
While interventions to prevent or reduce illicit drug
use have been proposed for use in schools and sites of employment, evidence
assessing preventive measures delivered in settings other than primary care
practice was outside the scope of the USPSTF review. However, the Centers for
Disease Control and Prevention's (CDC) Task Force on Community Preventive
Services has announced plans to assess the effectiveness of selected
population-based interventions for preventing or reducing abuse of drugs (other
than tobacco and alcohol) and to make recommendations based on these findings.
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Other Considerations
Research Needs/Gaps
The most significant
research gap identified by the USPSTF is the lack of studies to determine if
interventions found effective for treatment-seeking individuals with symptoms
of drug misuse are equally effective when applied to asymptomatic individuals identified
through screening. In addition, observational studies are needed to establish
more clearly the effect of treatment on social/legal problems and longer-term
health outcomes, including morbidity/mortality. More trials are needed that
specifically assess treatment outcomes for adolescents and pregnant women.
Further research is needed
to assess the clinical utility of validated standardized questionnaires designed
to screen for illicit drug use/misuse when they are applied in busy primary
care practice settings.
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Discussion
Burden
of Disease
The adverse health effects of illicit drug use can be
significant, but vary greatly depending on the type(s) of drug used and the mode,
amount, and frequency of use. Mortality among injection drug users is high due
to overdose and medical complications (e.g., HIV, hepatitis, bacterial
endocarditis) of injecting contaminated materials. Cocaine use can produce acute
cardiovascular and other complications (e.g., arrhythmias, myocardial
infarction, seizures).1 In addition, chronic use of marijuana has been
associated with respiratory inflammation and increased risk of airway cancers.2
The indirect legal, social, and
economic consequences of illicit drug use are equally important. Violence and
other criminal activities related to illegal drugs take a tremendous toll in
many communities, and illicit drug use is a major factor in the spread of HIV
infection. Most of the total economic burden of illicit drug use is related to
the costs of crime and incarceration. Deaths and illness account for 17% of
these costs, with almost 10% of the total being associated with HIV/AIDS.
Workplaces also suffer economically due to reduced productivity.3
Illicit drug use by pregnant
women has been shown to adversely affect both mother and fetus in multiple
ways, including decreased likelihood of seeking adequate prenatal care and
reduced gestational length and birth weight.4 In addition, illicit drug use
increases the risk for child abuse and family violence. Living as a child with
someone who abuses drugs is associated with long-term negative outcomes,
including an increased likelihood of illicit drug use.5 The age at which
drug use was initiated predicts subsequent abuse and dependence, with higher
rates observed among persons who initiate use at younger ages. This trend has
been observed in all demographic groups.6
Scope of Review
In 1996, the USPSTF concluded that there was
insufficient evidence to recommend for or against routine screening for drug
abuse with standardized questionnaires or biologic assays (a grade C
recommendation). To update this conclusion, the USPSTF conducted a staged
review of literature published on this topic between 1994 and January 2006.7
The review first sought to determine the sufficiency of evidence to establish
links between screening for illicit drug use, treatment, and clinically
meaningful health benefits. Since sufficient evidence to support these critical
linkages was lacking, a full systematic review of the topic was not undertaken.
The review targeted the four categories of illicit drugs whose use has been
studied most extensively: heroin, cocaine, marijuana, and multiple substances.
While misuse of prescription-type medications has been recognized as a growing
public health problem in the United States, there was insufficient published
research on detection or treatment of the problem to warrant a systematic
review of this topic. AHRQ staff conducted a separate review of recent
literature on the accuracy, reliability, and clinical utility of instruments
designed to screen for drug use among adolescents, adults and pregnant women.8
Accuracy of Screening Tests
Numerous standardized questionnaires,
many of them adaptations of instruments initially designed to detect alcohol
problems, have been developed and examined for validity and reliability in
identifying drug use/misuse. Most of these instruments, however, are too
lengthy to be considered for routine use as a screening tool in primary care
settings. Four questionnaires described in the literature appear potentially
useful for screening for illicit drug use in primary care. They range in length
from 4 to 20 items and their administration requires less than 5 minutes when
used by clinicians or self-administered by patients. There is good evidence
that the CRAFFT9 test can accurately and reliably detect drug use/misuse
among adolescents, and fair-to-good evidence for the accuracy and reliability
of the ASSIST10, CAGE-AID11 and DAST12 in detecting adults with drug
misuse. There is, however, insufficient evidence to assess the clinical utility
of these instruments when applied in primary care practice settings. Variability
in reported positive predictive values is of concern, with PPVs of 12 to 83% noted
when the questionnaires were assessed in a general medical care clinic. The
USPSTF found no assessment of the validity, reliability, or clinical utility of
any questionnaire for screening pregnant women for drug use.
Effectiveness of Early Detection
and Treatment
Many advances have
been made since 1996 in treating illicit drug use. Trials have found various pharmacotherapies
and/or behavioral interventions to be effective in reducing opiate, cocaine,
and cannabis misuse; however, follow-up periods for these studies have rarely been
more than six months in duration. In most trials, health outcomes were measured
by indices of mental or physical health symptoms (e.g., depressive symptoms)
rather than diagnosed health conditions (e.g., disability or STDs). Evidence of
the effect of treatment on social or legal outcomes is sparse and inconsistent,
although behavioral counseling interventions for cannabis misuse appear to
reduce cannabis-related problems. With one exception,13 the various
treatments have been studied in patients who have already developed medical,
social, or legal problems due to their drug use. It is uncertain how relevant these
findings are to asymptomatic populations identified through screening, as these
individuals may be less motivated to undergo treatment than more severely
impaired drug users.
Despite the expectation that
stopping or reducing drug use will translate into improved health outcomes,
there is only fair evidence of such an association. Changes in drug misuse or
injection practices among heroin or cocaine users have been associated with improved
adherence to needed medical treatment [e.g., use of highly active
antiretroviral therapy (HAART) by HIV-infected individuals] and slower disease
progression. Studies of birth outcomes, however, have yielded mixed results
with regard to the benefits of reducing or stopping cocaine and marijuana use
during pregnancy. There is limited evidence that treatment has a direct effect
on long-term morbidity and mortality. On the other hand, observational studies
conducted outside the United States have demonstrated an association,
regardless of the patient's history of treatment, between stopping opiate
(usually heroin) misuse and long-term improvement in mortality rates.
Potential
Harms of Screening and Treatment
The USPSTF found no
evidence of harms associated with screening for illicit drug use, although
failure to protect the confidentiality of positive results could potentially
affect a patient's employment, insurance coverage, or personal relationships.
There was also no evidence found of harms of behavioral interventions to treat
drug abuse problems. Adverse events ranging from mild (e.g., elevated liver
function tests) to serious (e.g., seizures) have been reported in trials of individuals
being treated for illicit drug use with opiate agonists, opiate antagonists,
and antidepressants. Some of the reported events appear to be associated with the
underlying drug use. The adverse events reported more frequently in the
treatment arm of trials (compared to placebo) have been those already cited on
product labels of the treatment medication.
Estimate
of the Magnitude of Net Benefit
In the absence of adequate evidence
that standardized instruments for identifying asymptomatic illicit drug users are
clinically useful in primary care settings, and that those identified through
screening will benefit from treatments known to be effective, the USPSTF was
unable to determine the balance of benefits and harms of screening for illicit drug
use.
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Recommendations of Others
Several professional groups have
recommended screening adolescents for drug use. The American Academy of Pediatrics recommends that pediatricians incorporate substance-abuse prevention into
daily practice, acquire the skills necessary to identify young people at risk
of substance abuse, and provide or facilitate assessment, intervention and
treatment as necessary.14 The American Medical Association's
(AMA) Guidelines for Adolescent Preventive Services (GAPS) recommends that
providers screen adolescents for substance abuse during annual preventive
services visits, using age-specific questionnaires that include items related
to drug use in the previous six months (www.ama-assn.org/ama/pub/category/1980.html).
In addition, the Bright Futures initiative includes a recommendation that all
adolescents be screened for substance use as part of an overall psychosocial
history. It suggests that practices use the CRAFFT questionnaire or the
patient self-administered Drug and Alcohol Problem Quick Screen (DAP) (www.brightfutures.org).
The American College of Obstetrics and Gynecology (ACOG) recommends direct questioning by clinicians of all
patients about their use of drugs (as well as tobacco and alcohol) as part of
periodic assessments. The use of screening instruments adapted from questionnaires
initially developed for use in detecting alcohol abuse is suggested, although
no specific instrument is specified.15
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References
1. National Institute on Drug
Abuse. Research Report Series. Cocaine abuse and addiction, 2004. Accessed
at: http://www.nida.nih.gov/PDF/RRCocain.pdf on January 15, 2008.
2. Kalant H. Adverse effects of
cannabis on health: an update of the literature since 1996. Prog
Neuropsychopharmacol Biol Psychiatry 2004;28(5):849-63.
3. Hogan C. Substance Abuse: The
Nation's Number One Health Problem. Princeton, NJ, Robert Wood Johnson
Foundation, 2001.
4. Rayburn WF, Bogenschultz MP.
Pharmacotherapy for pregnant women with addictions. Am J Obstet Gynecol
2004;6:1885-97.
5. Dube SR, Felitti VJ, Dong M,
Chapman DP, Giles WH, Anda RF. Childhood abuse, neglect, and household
dysfunction and the risk of illicit drug use: the adverse childhood
experiences study. Pediatrics 2003;111(3):564-72.
6. Substance Abuse and Mental Health
Services Administration. Results from the 2004 National Survey on Drug Use and
Health: National Findings. NSDUH series H-28, DHHS Publication No. SMA
05-4062. 2005. Rockville, MD.
7. Polen MR, Whitlock EP, Wisdom JP, Nygren P, Bougatsos C.
Screening in Primary Care Settings for Illicit Drug Use: Staged Systematic
Review for the U.S. Preventive Services Task Force. Evidence Synthesis No. 58,
Part 1. (Prepared by the Oregon Evidence-based Practice Center under Contract
No. 290-02-0024.) AHRQ Publication No. 08-05108-EF-1. Rockville, MD, Agency for Healthcare Research and Quality, January 2008. http://www.preventiveservices.ahrq.gov/clinic/uspstf08/druguse/drugsys.pdf [PDF Help].
8. Lanier D, Ko S. Screening in
Primary Care Settings for Illicit Drug Use: Assessment of Screening Instruments—A Supplemental Evidence Update for the U.S. Preventive Services Task Force.
Evidence Synthesis No. 58, Part 2. AHRQ Publication No. 08-05108-EF-2. Rockville, Maryland: Agency for Healthcare Research and Quality, January 2008. http://www.preventiveservice.ahrq.gov/clinic/uspstf08/druguse/drugevup.pdf. [PDF Help].
9. Knight JR, Sherritt L, Shrier LA,
Harris SK, Chang G. Validity of the CRAFFT substance abuse screening test
among adolescent clinic patients. Arch Pediatr Adolesc Med 2002;156:607-14.
10. Newcombe DL, Humeniuk RE, Ali R.
Validation of the World Health Organization Alcohol, Smoking and Substance
Involvement Screening Test (ASSIST): report of results from the Australian
site. Drug Alcohol Review 2005;24:217-26.
11. Brown RL, Rounds LA. Conjoint
screening questionnaires for alcohol and other drug abuse: criterion validity
in a primary care practice. Wis Med J 1995;94:135-40.
12. Staley D, El-Guebaly N. Psychometric properties of the Drug Abuse Screening
Test in a psychiatric patient population. Addictive Behaviors 1990;15:257-64.
13. Bernstein J, Bernstein E,
Tassiopoulos K, Heeren T, Levenson S, Hingson R. Brief motivational
intervention at a clinic visit reduces cocaine and heroin use. Drug Alcohol
Depend 2005;77(1):49-59.
14. Kulig JW and the Committee on
Substance Abuse. Tobacco, alcohol and other drugs: the role of the
pediatrician in prevention, identification and management of substance abuse.
Pediatrics 2005;115(3):816-21.
15. American College of Obstetrics and Gynecology. Guidelines for Women's Health Care, 2nd edition, 2002. Washington, D.C.
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Members of the U.S. Preventive Services Task Force*
Members
of the U.S. Preventive Services Task Force are are
Ned Calonge, MD, MPH, Chair, USPSTF (Chief Medical Officer and State
Epidemiologist, Colorado Department of Public Health and Environment, Denver,
CO); Diana B. Petitti, MD, MPH, Vice-chair, USPSTF (Keck Medical School, University of Southern California, Sierra Madre, CA); Thomas G. DeWitt, MD (Carl Weihl Professor of Pediatrics and Director of
the Division of General and Community Pediatrics, Department of Pediatrics,
Children's Hospital Medical Center, Cincinnati, OH); Leon Gordis, MD, MPH, DrPH (Professor, Epidemiology
Department, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD);
Kimberly D. Gregory, MD, MPH (Director, Women's Health Services Research and
Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Cedars-Sinai
Medical Center, Los Angeles, CA); Russell Harris, MD, MPH (Professor of
Medicine, Sheps Center for Health Services Research, University of North
Carolina School of Medicine, Chapel Hill, NC); George J. Isham, MD, MS,
(Medical Director and Chief Health Officer, HealthPartners, Inc., Minneapolis,
MN): Michael L. LeFevre, MD,
MSPH (Professor, Department of Family and Community Medicine, University of Missouri School of Medicine,
Columbia, MO); Carol Loveland-Cherry,
PhD, RN (Executive Associate Dean, Office of Academic Affairs, University of
Michigan School of Nursing, Ann Arbor, MI); Lucy N. Marion, PhD, RN (Dean and Professor, School of Nursing, Medical
College of Georgia, Augusta, GA); Virginia
A. Moyer, MD, MPH (Professor, Department of Pediatrics, University of Texas
Health Science Center, Houston, TX); Judith K. Ockene, PhD (Professor of
Medicine and Chief of Division of Preventive and Behavioral Medicine,
University of Massachusetts Medical School, Worcester, MA); George F. Sawaya, MD (Associate Professor, Department of Obstetrics,
Gynecology, and Reproductive Sciences and Department of Epidemiology and
Biostatistics, University of California, San Francisco, CA); Albert L. Siu, MD, MSPH (Professor and Chairman,
Brookdale Department of Geriatrics and Adult Development, Mount Sinai Medical
Center, New York, NY); Steven M. Teutsch, MD, MPH (Executive Director, Outcomes
Research and Management, Merck & Company, Inc., West Point, PA); and
Barbara P. Yawn, MD, MSPH, MSc (Director of Research, Olmstead Medical Center,
Rochester, MN).
*Members of the Task Force at the time this recommendation was finalized. For a list of current Task Force members, go to http://www.ahrq.gov/clinic/uspstfab.htm.
Disclaimer: Recommendations made by the USPSTF are independent of
the U.S. government. They should not be construed as an official position
of the Agency for Healthcare Research and Quality or the U.S.
Department of Health and Human Services.
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Copyright Information
This document is in the public domain within the United States. For
information on reprinting, contact Randie Siegel, Director, Division of
Printing and Electronic Publishing, Agency for Healthcare Research and Quality,
540 Gaither Road, Rockville, MD 20850.
Requests for linking or to incorporate content in electronic resources
should be sent to: info@ahrq.gov.
AHRQ Publication No. No. 08-05108-EF-3
Current as of January 2008
Internet Citation:
U.S. Preventive Services Task Force. Screening for Illicit Drug Use: U.S. Preventive Services Task Force Recommendation Statement. AHRQ Publication No. No. 08-05108-EF-3, January 2008. Agency for Healthcare Research and Quality, Rockville, MD. http://www.ahrq.gov/clinic/uspstf08/druguse/drugrs.htm