Background: For individuals with HIV, heavy drinking can pose serious threats to health. Some interventions are effective at reducing drinking in this population, but many HIV-infected heavy drinkers also use marijuana or cocaine. Although these drugs have predicted poor alcohol outcomes in other treatment studies, whether this occurs among HIV patients who drink heavily is unknown.

Methods: Participants were binge-drinking HIV primary care patients (N=254) enrolled in a randomized trial of three brief drinking interventions over 60 days that varied in intensity. We investigated the relationship of baseline past-year drug use (marijuana-only, cocaine-only, both, neither) to end-of-treatment drinking quantity and frequency. We also evaluated whether the relationship between intervention type and end-of-treatment drinking varied by baseline drug use. Final models incorporated control for patients' demographic and HIV characteristics.

Results: In final models, drinking frequency at the end of treatment did not vary by baseline drug use, but drinking quantity did (X(2)[3] = 13.87, p < 0.01), with individuals using cocaine-only drinking significantly more per occasion (B = 0.32, p < 0.01). Baseline drug use also interacted with intervention condition in predicting end-of-treatment drinking quantity (X(2)[6] = 13.98, p < 0.05), but not frequency, with the largest discrepancies in end-of-treatment drinks per drinking day by intervention intensity among cocaine-only patients.

Conclusions: In general, HIV patients using cocaine evidenced the highest levels of drinking after alcohol intervention. However, these individuals also evidenced the most pronounced differences in end-of-treatment drinking by intervention intensity. These results suggest the importance of more intensive intervention for individuals using alcohol and cocaine.