Correlates of engagement in group sex events among men who have sex with men in London who use geosocial-networking smartphone applications.

Men who have sex with men (MSM) who attend group sex events (GSEs) tend to also engage in high-risk sexual behaviors and substance use that may place them at additional increased risk for becoming infected with HIV. These sorts of events may be facilitated by the use of geosocial-networking smartphone applications, where MSM may have access to a large virtual pool of potential partners. The purpose of the current study was to examine the prevalence of recent engagement in GSEs and its demographic and behavioral correlates among a sample of MSM ( n = 202). Log-binomial models were fit to assess correlates of engagement in GSEs in the preceding three months. Overall, 42.6% had engaged in a GSE in the preceding three months. In multivariable models, the use of inhalant nitrites (PR: 2.239; 95% CI: 1.119, 4.848; p = .024) and methamphetamine (PR: 7.601; 95% CI: 2.340, 24.691; p = .001) were associated with recent engagement in GSEs. Given the high prevalence of these potentially high-risk behaviors, future research should be conducted to examine the concurrent use of substance use and condom use at the GSEs to develop appropriate risk reduction interventions.