Appendix.

<div><p>Stigma related to non-heteronormative behavior remains a major challenge associated with mental health disparities among gay, bisexual, and other men who have sex with men (GBM). Economic hardship worsens these challenges, and characterizing these interactions can help inform effective mental health interventions for GBM. Using 2018 and 2019 American Men’s Internet Survey data, we assessed population heterogeneity in sexual stigma experiences among adult, HIV-negative GBM using latent class analysis. We estimated associations between stigma patterns and mental health outcomes (psychological distress, suicidal ideation, and suicide attempt) using modified Poisson regression, quantifying the interaction between sexual stigma and poverty on multiplicative and additive scales. Four distinct sexual stigma patterns were identified that grouped GBM as experiencing: diverse forms of sexual stigma across multiple settings (12%); primarily anticipated stigma in healthcare settings (13%); predominantly enacted and perceived sexual stigma in family and general social settings (34%); or minimal sexual stigma (41%). Vulnerabilities to distinct stigma patterns varied by key participant demographics including age, nativity and education. Notably, the group with diverse stigma, particularly in the context of poverty, had significantly higher prevalence of serious psychological distress (aPR: 4.7 [95% CI: 3.9, 5.7]) and suicide attempts (aPR: 11.3 [95% CI: 6.6, 19.4]) compared to the group with minimal stigma and adequate income. These findings highlight the pivotal role of poverty in intensifying the impact of sexual stigma on the mental well-being of GBM. Addressing stigma within the broader context of structural determinants, including poverty, is crucial for optimizing mental health among GBM.</p></div>