Numerous partner and relationship characteristics are associated with sexual risk behavior among young men who have sex with men (YMSM), including being in a serious relationship and having older partners. However, most research in this area is limited by its reliance on variable-centered approaches. Using multilevel latent class analysis, this study identified subgroups of sexual partner types with a particular emphasis on examining whether partner type moderated the association between drug use and condomless anal sex (CAS). Data were utilized from an ongoing cohort study of YMSM (ages 16-29) recruited from previous studies as well as peers and serious partners of existing cohort members. A total of 469 participants reported on 1596 sexual partners in the past 6 months. We identified four distinct sexual partner typologies, which we refer to as: casual, older-online, much older, and serious. Results indicated that rates of CAS were highest for older-online and serious partners. Additionally, there was a positive association between drug use and CAS among a predominantly marijuana using sample, but only for serious partners. While previous research has found that CAS is highest in serious relationships, findings suggest that there may be another type of partnership in which CAS is likely to occur (older partners met online). If confirmed, these results suggest interventions focused on the intersection of marijuana use and CAS may be particularly important among YMSM with serious partners.
Keywords: Drug use; Men who have sex with men; Sexual orientation; Sexual risk behavior.