Psychosocial interventions to reduce alcohol consumption in concurrent problem alcohol and illicit drug users

Problem alcohol use is common among people who use illicit drugs (PWID) and is associated with adverse health outcomes. It is also an important factor contributing to a poor prognosis among drug users with hepatitis C virus (HCV) as it impacts on progression to hepatic cirrhosis or opioid overdose in PWID.

To assess the effectiveness of psychosocial interventions to reduce alcohol consumption in PWID (users of opioids and stimulants).

We searched the Cochrane Drugs and Alcohol Group trials register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, CINAHL, and PsycINFO, from inception up to August 2017, and the reference lists of eligible articles. We also searched: 1) conference proceedings (online archives only) of the Society for the Study of Addiction, International Harm Reduction Association, International Conference on Alcohol Harm Reduction and American Association for the Treatment of Opioid Dependence; and 2) online registers of clinical trials: Current Controlled Trials, ClinicalTrials.gov, Center Watch and the World Health Organization International Clinical Trials Registry Platform.

We included randomised controlled trials comparing psychosocial interventions with other psychosocial treatment, or treatment as usual, in adult PWIDs (aged at least 18 years) with concurrent problem alcohol use.

We used the standard methodological procedures expected by Cochrane.

We included seven trials (825 participants). We judged the majority of the trials to have a high or unclear risk of bias.The psychosocial interventions considered in the studies were: cognitive-behavioural coping skills training (one study), twelve-step programme (one study), brief intervention (three studies), motivational interviewing (two studies), and brief motivational interviewing (one study). Two studies were considered in two comparisons. There were no data for the secondary outcome, alcohol-related harm. The results were as follows.Comparison 1: cognitive-behavioural coping skills training versus twelve-step programme (one study, 41 participants)There was no significant difference between groups for either of the primary outcomes (alcohol abstinence assessed with Substance Abuse Calendar and breathalyser at one year: risk ratio (RR) 2.38 (95% confidence interval [CI] 0.10 to 55.06); and retention in treatment, measured at end of treatment: RR 0.89 (95% CI 0.62 to 1.29), or for any of the secondary outcomes reported. The quality of evidence for the primary outcomes was very low.Comparison 2: brief intervention versus treatment as usual (three studies, 197 participants)There was no significant difference between groups for either of the primary outcomes (alcohol use, measured as scores on the Alcohol Use Disorders Identification Test (AUDIT) or Alcohol, Smoking and Substance Involvement Screening Test (ASSIST) at three months: standardised mean difference (SMD) 0.07 (95% CI -0.24 to 0.37); and retention in treatment, measured at three months: RR 0.94 (95% CI 0.78 to 1.13), or for any of the secondary outcomes reported. The quality of evidence for the primary outcomes was low.Comparison 3: motivational interviewing versus treatment as usual or educational intervention only (three studies, 462 participants)There was no significant difference between groups for either of the primary outcomes (alcohol use, measured as scores on the AUDIT or ASSIST at three months: SMD 0.04 (95% CI -0.29 to 0.37); and retention in treatment, measured at three months: RR 0.93 (95% CI 0.60 to 1.43), or for any of the secondary outcomes reported. The quality of evidence for the primary outcomes was low.Comparison 4: brief motivational intervention (BMI) versus assessment only (one study, 187 participants)More people reduced alcohol use (by seven or more days in the past month, measured at six months) in the BMI group than in the control group (RR 1.67; 95% CI 1.08 to 2.60). There was no difference between groups for the other primary outcome, retention in treatment, measured at end of treatment: RR 0.98 (95% CI 0.94 to 1.02), or for any of the secondary outcomes reported. The quality of evidence for the primary outcomes was moderate.Comparison 5: motivational interviewing (intensive) versus motivational interviewing (one study, 163 participants)There was no significant difference between groups for either of the primary outcomes (alcohol use, measured using the Addiction Severity Index-alcohol score (ASI) at two months: MD 0.03 (95% CI 0.02 to 0.08); and retention in treatment, measured at end of treatment: RR 17.63 (95% CI 1.03 to 300.48), or for any of the secondary outcomes reported. The quality of evidence for the primary outcomes was low.

We found low to very low-quality evidence to suggest that there is no difference in effectiveness between different types of psychosocial interventions to reduce alcohol consumption among people who use illicit drugs, and that brief interventions are not superior to assessment-only or to treatment as usual. No firm conclusions can be made because of the paucity of the data and the low quality of the retrieved studies.