Untangling global mental health disparities in the Canadian population: Exploring the intersection of sexual orientation, stress, and social support.

This study investigated whether disparities in global mental health associated with multidimensional sexual orientation (SO)—including self-identified and behavioural SO—are mediated by perceived daily stress, social support, and their interaction, using a nationally representative Canadian sample of 80,985 adults aged 18–64. Analyses stratified by gender found that higher stress and lower social support partially mediated poorer mental health among self-identified bisexual individuals and those reporting no sexual partners in the past 12 months, but not among other SO categories such as gay/lesbian identities or those with exclusively same-gender partners. The mediating effects were stronger for bisexual women than men, and social support’s buffering effect on stress was particularly relevant for those without recent sexual partners. While stress and social support explained some mental health disparities linked to SO, the overall mediation magnitudes were modest, suggesting additional factors contribute to these disparities. The study highlights the importance of fostering social support and reducing stressors, especially for bisexual populations and those without recent sexual partners, while noting limitations including exclusion of non-binary and other minority SO groups and the cross-sectional design.