BACKGROUND: The use of multiple illicit drugs (polydrug use) is associated with health-related harms and elevated risk of drug overdose. Polydrug use in common among women who use 'hard' drugs, such as cocaine, heroin or methamphetamine.
METHODS: Quantitative data collection was conducted with a community-recruited sample of 624 women who used heroin, methamphetamine or cocaine in Oakland, CA during 2014-2015. We conducted latent class analysis to classify polydrug use patterns. We assessed associations between classes of polydrug use and infectious disease risk behaviors, health care utilization and unmet health care need.
RESULTS: We identified four distinct classes of drug use: (1) predominantly crack (52% of women); (2) powder cocaine & non-heroin opioids (8%); (3) moderate polydrug use (25%); (4) heavy polydrug use (15%). Odds of sexual risk, injection drug use and unmet healthcare need were twice as high in the heavy polydrug use class as the predominantly crack class (p > 0.01 for each outcome). The rate of binge drinking (as days per month) was also significantly higher in the heavy polydrug class (p = 0.01). The moderate polydrug use class had higher odds of injection drug use and drug treatment participation, compared to the mainly crack class (p < 0.001 for each outcome). There were no differences between classes in health insurance or health care utilization.
DISCUSSION: Reduction of polydrug use could be an effective harm reduction strategy to address sexual and injection risk among women. The use of both opioids and stimulants in three of the four classes suggests that multi-modal substance abuse treatment approaches may be most appropriate.