The additive effects of depressive symptoms and polysubstance use on HIV risk among gay, bisexual, and other men who have sex with men

•Increased odds for high-risk sex was seen only at the highest levels of concurrent polysubstance use and depressive symptoms.•18.2% of the effect of depressive symptoms on condomless anal sex with serodiscordant or unknown status partners was explained by polysubstance use.•Neither Alcohol Use, nor AUDIT scores were associated with condomless anal sex with serodiscordant or unknown status partners.