Expanding Medicaid to Reduce Human Immunodeficiency Virus Transmission in Houston, Texas: Insights From a Modeling Study.

CONTEXT: Medicaid expansion has been nationally shown to improve engagement in the human immunodeficiency virus (HIV) treatment and prevention continua, which are vital steps to stopping the HIV epidemic. New HIV infections in the United States are disproportionately concentrated among young Black men who have sex with men (YBMSM). Houston, TX, is the most populous city in the Southern United States with a racially/ethnically diverse population that is located in 1 of 11 US states that have not yet expanded Medicaid coverage as of 2021. METHODS: An agent-based model that incorporated the sexual networks of YBMSM was used to simulate improved antiretroviral treatment and pre-exposure prophylaxis (PrEP) engagement through Medicaid expansion in Houston, TX. Analyses considered the HIV incidence (number of new infections and as a rate metric) among YBMSM over the next 10 years under Medicaid expansion as the primary outcome. Additional scenarios, involving viral suppression and PrEP uptake above the projected levels achieved under Medicaid expansion, were also simulated. RESULTS: The baseline model projected an HIV incidence rate of 4.96 per 100 person years (py) and about 368 new annual HIV infections in the 10th year. Improved HIV treatment and prevention continua engagement under Medicaid expansion resulted in a 14.9% decline in the number of annual new HIV infections in the 10th year. Increasing viral suppression by an additional 15% and PrEP uptake by 30% resulted in a 44.0% decline in new HIV infections in the 10th year, and a 27.1% decline in cumulative infections across the 10 years of the simulated intervention. FINDINGS: Simulation results indicate that Medicaid expansion has the potential to reduce HIV incidence among YBMSM in Houston. Achieving HIV elimination objectives, however, might require additional effective measures to increase antiretroviral treatment and PrEP uptake beyond the projected improvements under expanded Medicaid.

Sex Partner Behavior Variation Related to Network Position of and Residential Proximity to Sex Partners Among Young Black Men Who Have Sex with Men.

This analysis examines how sex behaviors are influenced by a sex partner's network bridging position and the residential proximity between the two. The study sample consisted of 437 young black men who have sex with men (YBMSM) in Chicago and their sex partners (2013-2014). Dyadic analyses that clustered on individuals using generalized estimating equations (n = 1095 relationships) were conducted to assess the associations between different HIV-related sexual behaviors and the network position of and residential proximity to a partner. The odds of group sex was higher with partners who had high network bridging, regardless of how close they lived to one another. The odds of transactional sex was higher with partners who had high network bridging and lived in a different region of the city. Sex behaviors associated with an increased risk of HIV transmission were associated with the network structural position of and residential proximity to partners among YBMSM.