Intersectional Stigma and Pre-Exposure Prophylaxis Use Among Female Sex Workers in Namibia

Abstract

Background: Female sex workers (FSW) in sub-Saharan Africa face disproportionate vulnerability to HIV, and are prioritized for HIV prevention interventions, including daily oral pre-exposure prophylaxis (PrEP). Intersectional stigma and discrimination related to their multiple marginalized social identities and positions may influence their engagement with interventions. This dissertation used a sequential mixed methods design to explore manifestations of intersectional stigma among FSW in Namibia and their impacts on PrEP use. Methods: We conducted in-depth interviews (IDIs) with FSW (n=21), PrEP providers (n=13), and FSW-serving stakeholders (n=8) to identify drivers and manifestations of intersectional stigma and develop a model of intersectional stigma’s impacts on PrEP use. We then used exploratory factor analysis (EFA) methods to develop and psychometrically evaluate scales measuring intersectional stigma among FSW using PrEP (n=214). Finally, we used structural equation modeling (SEM) to estimate the paths between stigma dimensions and recent PrEP adherence via social cohesion, resilience, and depression among PrEP-experienced FSW in Namibia (n=100). Results: Qualitatively, we found that sex work stigma intersected with stigma and discrimination related to class, poverty, migration status, and race or ethnicity to influence FSWs’ experiences of social cohesion, resilience, and engagement with healthcare and PrEP services. We further found that PrEP was a source of empowerment for FSW. Through EFA, we identified three dimensions of stigma: experienced stigma (α=0.88), anticipated stigma (α=0.84), and PrEP stigma (α=0.45). The scales were positively correlated with racial discrimination and depressive symptoms, supporting their construct validity. Our SEM identified an indirect positive relationship between PrEP stigma and PrEP adherence via depression (β=0.211, p=0.042), a direct negative relationship between experienced intersectional stigma and adherence (β=-0.503, p=0.043), and a direct positive relationship between resilience and adherence (β=0.605, p=0.007). Conclusion: This dissertation provides insight into the manifestations and measurement of intersectional stigma, the mechanisms through which they influence PrEP use, and the magnitude and direction of the relationship of different stigma domains with PrEP adherence among FSW using PrEP in Namibia. Findings underscore the importance of fostering resilience to improve oral PrEP adherence among multiply marginalized FSW, and the centrality of intersectional approaches in research and intervention development