Different Classes of Crystal Methamphetamine Use Are Associated with Psychological and Sexually Transmitted Infection Outcomes Among Gay, Bisexual, and Other Men Who Have Sex with Men

We examined how different patterns of crystal methamphetamine (CM) use are associated with different psychosocial and sexual health outcomes among gay, bisexual, and other men who have sex with men (GBM). We used latent class analysis to identify different patterns of CM use with the ASSIST scale for GBM who report using CM (n = 228), and examined how these classes differed from each other and from GBM who do not use CM (n = 2221). Results: We found four CM-use classes based on ASSIST responses. Classes defined by occasional use but few problems were more likely to test positive for STIs, while classes defined by more frequent use and problems were less likely to have STIs, but reported greater psychosocial problems. Interventions should focus on tailored substance use counselling and health promotion strategies to address the diversity of problems faced by GBM who use CM.