Minority Stress, Stimulant Use, and HIV among Sexual Minority Men: A Biopsychosocial Approach - PROJECT SUMMARY/ABSTRACT Sexual minority men (SMM; i.e., non-heterosexual men) in the US are impacted by intertwining epidemics of HIV and stimulant use (e.g., methamphetamine, powder cocaine, crack cocaine) at disparate rates compared to their heterosexual peers. Findings from our team and others demonstrate that SMM with HIV who use stimulants have greater difficulties successfully navigating the HIV care continuum as well as display substantially elevated viral load, amplified HIV transmission risk, and faster clinical HIV progression. The dominant theory used to explain health disparities among SMM is minority stress theory, which states that these disparities are the result of stigma-related social stressors (e.g., discrimination, internalized homonegativity). While evidence of the association between minority stress and stimulant use exists, few studies have directly examined associations between minority stress and biological HIV outcomes, such as viral load, and many rely solely on self-report measures (as opposed to laboratory testing) to assess these outcomes. The Biopsychosocial Minority Stress Framework (BMSF) has been proposed to link minority stress to biological health, and posits that: (a) minority stress directly affects the health behaviors and psychological health of SMM; (b) SMM’s health behaviors and psychological health indicators are interrelated; and (c) these factors influence biological health among SMM via the immune system. Applying the BMSF to SMM with HIV, stimulant use and ART nonadherence (health behaviors) may serve as mediators through which minority stress impacts viral load (an outcome critical to immune health) and, thereby, other health outcomes (e.g., opportunistic infections and cancers). Further, consistent with intersectionality theory, racial/ethnic minority SMM may experience intensified effects of minority stress that could contribute to the increased burden of HIV and stimulant use observed among SMM of color in the US. Understanding the mechanisms through which minority stress impacts viral load, and thereby other health outcomes, has important implications for intervention among SMM with HIV who use stimulants. As such, we propose to systematically test associations posited by the BMSF in this high-priority population using a series of mediation analyses. Specifically, we aim to examine BMSF components by testing longitudinal associations between minority stress, stimulant use, ART nonadherence, and laboratory testing-derived viral load using existing data from two independent samples of SMM with HIV who use stimulants: (1) 110 SMM residing in San Francisco, CA and (2) 350 SMM recruited from across the US. Further, we aim to test whether the associations between minority stress, stimulant use, ART nonadherence, and viral load differ among racial/ethnic minority versus majority (i.e., non-Hispanic White) SMM with HIV who use stimulants, using multigroup analyses to assess the invariance of effects examined in Aims 1 and 2. Support for this project will greatly help in furthering the PI toward his long-term goal of becoming an independent academic clinical psychologist with expertise in studying the biopsychosocial mechanisms underlying sexual and gender minority health disparities.