Association of Partnership-Level Methamphetamine Use on Inconsistent PrEP Care Engagement Among GBMSM in Los Angeles County.

There are limited quantitative studies describing the association between meth use in the context of male-male sexual partnerships and PrEP care engagement. We assessed the longitudinal relationship between individual and partnership level meth use with inconsistent PrEP engagement among young gay, bisexual and other men who have sex with men (GBMSM) in Los Angeles. The primary exposure was meth use at the partnership level with a ternary variable (neither partner nor participant used meth, either used meth, or both used meth). Generalized estimating equations were used to assess odds of inconsistent PrEP engagement at different levels of partner-participant meth use, adjusting for age at visit, number of recent male partners and partner intimacy. Among inconsistent PrEP engagement, 61% (n = 84, vs. 79.5%, n = 346 continuous) reported that neither they nor their partner used meth, 22% (n = 31, vs. 18%, n = 56) reported that either partner or participant used meth and 17% (n = 24, vs. 8%, n = 33) reported that both partner and participant used meth (P < 0.01). There were increased odds of inconsistent PrEP engagement when both partner and participant reported meth use (aOR: 3.82; 95%CI: 1.83-7.99) and when either partner or participant reported meth use (aOR: 2.46; 95%CI: 1.28-4.75). Meth use plays an important role in consistent PrEP engagement among GBMSM in mSTUDY. PrEP users who use meth with partners may benefit from integrated interventions addressing both meth use and PrEP engagement.