The scientific purpose of this study is to look at how substance use may relate to human immunodeficiency virus (HIV) infection among young black men who have sex with men in Atlanta.

Young black men who have sex with men (YBMSM) are a critically at-risk population in the United States and Atlanta that faces extremely high incidence rates of HIV and other sexually transmitted infections (STIs). The understanding of what places this group of men at high risk is incomplete, and the role of substances in amplifying that risk is unclear. This study will fill a number of gaps about how substances and partnerships place YBMSM at increased HIV risk. The study includes several innovative aspects. First, the investigators are using a theoretical framework to understand multilevel associations between substance use and HIV risk behavior in YBMSM in the southeastern United States, a critically at-risk but understudied population. Second, the investigators are using a variety of enhanced measurement methods to understand these associations. The investigators are supplementing self-reported substance use with objective measures to enhance the sensitivity of classifying recent use. The investigators will analyze incident HIV/STI endpoints in addition to self-reported sexual behaviors. The investigators will use detailed, event-based and dyadic measures of substance use and its covariates, which will capture both sexual and non-sexual contexts of use. Although previous cohort studies have explored alcohol and drug use during sexual events among men who have sex with men (MSM), few studies have described both sexual and non-sexual patterns of, and motivations for, substance use among YBMSM, and none have incorporated longitudinal biomarkers of substance use and related these to incident infection outcomes. Finally, the investigators are using a mixed-methods approach to provide context to the quantitative findings. By recruiting subjects to a nested qualitative study within the larger cohort based on their interval-specific risks, the investigators will gain in-depth information regarding the emergence, persistence, and resolution of these complex relationships between substances and sexual risk behaviors among YBMSM and how these relationships emerge and are resolved over time.

Inclusion Criteria:

• male at birth
• currently identifies as male
• age ≥18 years and < 30 years at enrollment
• had anal sex with a man in lifetime
• has had any sex with a man in the past 3 months
• self-reported race is black/African American
• lives in Atlanta area and plans to remain for 2 years
• is able to complete the survey instruments in English
• is willing to provide at least 2 means of contact
• is willing to be re-contacted for the return of HIV/STI testing results, and for other study reasons as necessary
• is not enrolled in an HIV prevention trial

Exclusion Criteria:

• self-reported multiple or non-Black/African American race(s)
• self-reported Hispanic ethnicity
• (for prospective follow-up) participant screens HIV-positive

Young black men who have sex with men in Atlanta, Georgia will be recruited in a variety of venues in Atlanta. If needed, there will be targeted recruitment via Facebook.