Patterns of Social Support and LGBTQ + Community Involvement Among Gay, Bisexual, and Other Men Who Have Sex with Men in Australia and Their Effect on HIV-Related Outcomes: A Latent Class Analysis.

Peer support from social networks of gay, bisexual, and other men who have sex with men (GBMSM) has been recognised as a critical driver of engagement with HIV prevention. Using data from an online cross-sectional survey of 1,032 GBMSM aged 18 or over in Australia, a latent class analysis was conducted to categorise participants based on social support, LGBTQ + community involvement, and social engagement with gay men and LGBTQ + people. Comparisons between classes were assessed using multivariable multinomial logistic regression. Participants were allocated into four classes: 'Gay men focused' (n = 293, 28.4%) with high levels of support from gay men, 'High and diverse' (n = 75, 7.3%) with high support from people with a range of gender and sexual identities, 'Moderate overall' (n = 177, 17.2%) who reported some support from all sources, and 'Low overall' (n = 487, 47.2%) who had low support. Lifetime HIV testing was lower in the 'Low overall' (78.0%) and 'Moderate overall' (81.9%) classes compared to the 'Gay men focused' (96.9%) and 'High and diverse' (93.3%) groups. Among non-HIV-positive participants (n = 971), lifetime PrEP use was lower in the 'Low overall' (28.9%) than the 'Gay men focused' group (56.2%) but similar in the 'High and diverse' (59.7%) and 'Moderate overall' (37.5%) groups. Greater levels of social engagement with gay men and LGBTQ + people were associated with higher levels of HIV testing and PrEP use. Interventions are needed to reach GBM who are less engaged with GBMSM networks or LGBTQ + communities.