Background: Individual sexual risk behaviors have failed to explain the observed racial disparity in HIV acquisition. To increase understanding of potential drivers in disparities, we assessed differences across individual, network, and social determinants. Methods: Data come from RADAR (N=1015), a longitudinal cohort study of multilevel HIV-risk factors among young men who have sex with men (YMSM) aged 16–29 in Chicago. Data collection includes biological specimens; network data, including detailed information about social, sexual, and drug-use networks; and psychosocial characteristics of YMSM. Results: Compared to white YMSM (24.8%) and Hispanic YMSM (30.0%), black YMSM (33.9%) had a higher prevalence of both HIV (32%; p<0.001) and rectal STIs (26.5%; p=0.011) with no observed differences in PrEP use. Black YMSM reported lower rates of sexual risk behaviors and more lifetime HIV tests (p<0.001) compared to all other YMSM, however, were also significantly less likely to achieve viral suppression (p=0.01). Black YMSM reported the highest rate of cannabis use (p=0.03) as well as greater levels of stigma (p<0.001), victimization (p=0.04), trauma (p<0.001), and childhood sexual abuse (p<0.001). White YMSM reported higher rates of depression (p<0.001) and alcohol use (p<0.001). In network analyses, significant differences existed across network characteristics with black YMSM having the lowest transitivity (p=0.002), the highest density (p<0.001), and the highest homophily (p<0.001). Conclusion: Black YMSM do not report higher rates of HIV risk behaviors, but social and network determinants are aligned towards increased HIV risk. These results suggest that network interventions and those addressing social determinants may help reduce disparities.

No abstract

Understanding pre-exposure prophylaxis (PrEP) discontinuation is key to maximizing its effectiveness at the individual and population levels. Data came from the RADAR cohort study of MSM aged 16-29 years, 2015-2017. Participants included those who reported past 6-month PrEP use and discontinued its use by the interview date. Of the 197 participants who had used PrEP in the past 6 months, 65 discontinued use. Primary reasons for PrEP discontinuation included trouble getting to doctor's appointments (14, 21.5%) and issues related to insurance coverage or loss (13, 20.0%). Few (21%) who discontinued spoke to their doctor first, which has important implications for future long acting formulations.

Critical to the development of improved HIV elimination efforts is a greater understanding of how social networks and their dynamics are related to HIV risk and prevention. In this paper, we examine network stability of confidant and sexual networks among young black men who have sex with men (YBMSM). We use data from uConnect (2013–2016), a population-based, longitudinal cohort study. We use an innovative approach to measure both sexual and confidant network stability at three time points, and examine the relationship between each type of stability and HIV risk and prevention behaviors. This approach is consistent with a co-evolutionary perspective in which behavior is not only affected by static properties of an individual's network, but may also be associated with changes in the topology of his or her egocentric network. Our results indicate that although confidant and sexual network stability are moderately correlated, their dynamics are distinct with different predictors and differing associations with behavior. Both types of stability are associated with lower rates of risk behaviors, and both are reduced among those who have spent time in jail. Public health awareness and engagement with both types of networks may provide new opportunities for HIV prevention interventions.