Internalized HIV stigma and viral suppression: examining the mediating and moderating roles of substance use and social support.

Objective: To examine the effects of internalized HIV stigma on viral non-suppression via depressive symptoms, alcohol use, illicit drug use, and medication adherence and investigate whether social support moderates these effects.

Design: Longitudinal observational clinical cohort of patients in HIV care in the US.Methods: Data from the CFAR Network for Integrated Clinical Systems (2016-2019) were used to conduct structural equation models (SEM) to test the indirect effects of internalized HIV stigma on viral non-suppression through depressive symptoms, illicit drug use, alcohol use, and medication adherence. Moderated mediation with an interaction between social support and internalized HIV stigma was examined.

Results: Among 9,574 individuals included in the study sample, 81.1% were male and 41.4% were Black, non-Hispanic. The model demonstrated good fit (root mean square error of approximation = 0.028; standardized root means square residual = 0.067). The overall indirect effect was significant (b = 0.058; se  = 0.020; β = 0.048; 95%CI = .019-.098), indicating that internalized HIV stigma's impact on viral non-suppression was mediated by depressive symptoms, illicit drug use, and medication adherence. An interaction was observed between internalized HIV stigma and social support on alcohol use, however, there was no moderated mediation for any of the mediators.

Conclusions: Internalized HIV stigma indirectly impacts viral non-suppression through its effects on depressive symptoms, illicit drug use, and medication adherence. Social support may buffer the impact, but more research is needed. Understanding the pathways through which internalized stigma impacts viral suppression is key to improving health of people with HIV.