Reduction and Cessation of Alcohol, Cannabis, and Stimulant Use: Prospective Associations With Changes in Depressive Symptoms Across Two Cohort Studies of Sexual and Gender Minorities.

Sexual and gender minorities (SGM) are at increased risk for substance use and depression. However, little research has examined the directionality of associations between substance use and depression in this high-risk population, and we are not aware of any to parse associations between depression and changes in the frequency of substance use versus substance use cessation. Such research can help to inform the development of future interventions to address health disparities affecting SGM. We used data from two longitudinal cohorts of SGM assigned male at birth (SGM-AMAB; N = 1,418) to examine associations between changes in frequency of alcohol, cannabis, and stimulant use and depressive symptoms. Multilevel models tested whether changes in substance use predicted changes in depressive symptoms and vice versa. Results indicate that when SGM-AMAB decreased their alcohol use or ceased alcohol, cannabis, or stimulant use, they experienced concurrent decreases in depressive symptoms. Only reducing stimulant use (not alcohol or cannabis use) was associated with decreases in depressive symptoms over the subsequent 6 months. Depressive symptoms did not prospectively predict cessation or reduction in the use of any substance. These findings suggest that clinical interventions targeting substance use may simultaneously reduce depressive symptoms and that reductions in alcohol use (even in the absence of cessation) may simultaneously benefit mental health among SGM-AMAB. The limited evidence of prospective effects over 6 months suggests that studies with shorter lags may be better equipped to examine the directionality of the association between depressive symptoms and substance use/reduction.