Significance. Use of stimulants is a growing problem in the US. This growing public health crisis requires expanded research to explore its reach, drivers and impact, including on marginalized groups, such as Black gay, bisexual and other men who have sex with men (MSM), a critical population that is disproportionately impacted by HIV. Estimates of the incidence and persistence of stimulant use in Black MSM is needed, as well as research on how it co-occurs with other drug use (i.e. polysubstance use), its social-environmental drivers, and its impact on HIV transmission. Research Plan. In Aim 1, we will characterize stimulant use in an established cohort of Black MSM, including co-occurring use with other drugs (i.e. polysubstance use) and use over time (e.g., incidence, persistence). In Aim 2, we will identify network-level (e.g. disassortative racial mixing, network turnover) and neighborhood-level (e.g., social cohesion, time spent in gay neighborhoods) drivers of stimulant use in Black MSM. In Aim 3, we will assess how stimulant use impacts HIV transmission in Black MSM through HIV prevention (e.g. PrEP adherence, condom use), HIV treatment (e.g. ART adherence, viral suppression) and biological vulnerability (e.g. rectal cytokines). The ongoing Neighborhoods and Networks (N2) Cohort Study (R01MH112406; PIs: Duncan & Schneider) provides an ideal opportunity to conduct the proposed study. N2 includes 186 HIV-positive and 227 HIV-negative Black MSM living in Chicago. Data being collected include stimulant use at multiple cycles, in-depth assessments of neighborhoods (including real-time geospatial methods to track mobility within and between neighborhoods), multiple social network typologies, and HIV-related prevention and treatment behaviors. The proposed study will use N2 data to conduct Aims 1-3. We also propose to use existing N2 infrastructure to recruit 30 current stimulant-using and 10 non-stimulant-using HIV-negative Black MSM from the N2 study, and conduct in-depth interviews with them using a timeline follow-back survey focused on stimulant use and sexual risk behavior, as well as collect rectal swabs, urine and blood samples as objective biomarkers, in order to explore in-depth how stimulant use contributes to HIV transmission. The results of this study will inform the development of an R34 proposal to develop and test an intervention that addresses stimulant use and HIV in a critical population. Team. Investigators with expertise in stimulant use, HIV, social network analysis, spatial epidemiology, immunology, integration of biological and behavioral research, and mixed methods research will conduct this research together. Public Health Impact. The proposed study will be a large, rigorous and innovative study of stimulant use, its social-environmental drivers and its impact on HIV transmission in Black MSM, a group with a heavy burden of stimulant use and HIV. The proposed study is aligned with multiple NIDA funding priorities, including NOT-DA-19-066 Epidemiology of Drug Abuse, has a high likelihood of success by leveraging an existing cohort, and will directly inform an R34 proposal to develop and test an intervention that addresses stimulant use and HIV in a critical population.

Use of stimulants is a growing problem in the US, including in marginalized groups, such as in Black gay, bisexual and other men who have sex with men (MSM). The proposed scientifically rigorous, exploratory R21 study aims to increase our understanding of stimulant use and other drug use in Black MSM by using the data and infrastructure of an established cohort (the Networks and Neighborhoods Cohort Study) to characterize stimulant use and other drug use, identify it’s social-environmental drivers, and assess its contribution to HIV transmission. The findings will directly inform an R34 proposal to develop and test an intervention that addresses stimulant use and HIV in a critical population.