Theses Doctoral

Substance use and HIV risk behavior among black South African men who have sex with men

Knox, Justin R.

Black South African men who have sex with men (MSM) face a set of adverse circumstances, including economic hardship and stigmatization, that combine to put them at an elevated risk for hazardous substance use and HIV infection. This creates a context where substance use is normative and high-risk sexual behavior is often engaged in covertly and under the influence of intoxicating substances. The overarching objective of this dissertation was to explore determinants of hazardous drinking and HIV risk behavior among black South African MSM with a particular focus on the role of social networks. In order to achieve this, I used data drawn from the study, “HIV and Sexual Risk in African MSM in South African Townships” (R01-MH083557; PI: Sandfort, PhD). First, I conducted a systematic literature review to identify studies that used social network analysis to evaluate alcohol use among adults in order to answer the question: how have social network characteristics been shown to influence adults’ drinking behaviors, both in terms of characteristics of their network structures and characteristics of their network ties? Results of the review demonstrated that characteristics of one’s peers as well as social network structure influenced egos’ alcohol consumption in a variety of ways and across settings. Second, I described drug and alcohol use among black South African MSM and identified determinants of hazardous drinking, a highly prevalent form of alcohol use identified in the sample. The results showed that hazardous drinking was highly prevalent and multiple indicators of social vulnerability were identified as independent determinants of hazardous drinking. Third, I assessed the relationship between substance use and sexual risk behavior and explored the moderating effects of psychosocial factors. The results showed that there was not a main effect between substance use and sexual risk behavior; however, among men with high intentions to engage in safer sex, substance use was associated with increased risky sexual behavior. Overall, this dissertation increased our understanding of social networks, substance use and HIV risk behavior among black South African MSM. Our results suggest the importance of using pre-existing social networks to deliver potential interventions. The results also suggest that the most vulnerable members of this community are at increased risk of hazardous drinking. Lastly, efforts to reduce HIV risk behavior should focus on both increasing safer sex intentions and negating the impact of substance use on sexual risk behavior. Taken together, these studies provide insight for developing potential interventions, including intervention that use social network data to facilitate behavioral change, as well as undertaking further research among a critical population.

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More About This Work

Academic Units
Thesis Advisors
Hasin, Deborah
Ph.D., Columbia University
Published Here
November 17, 2017