Patient and Facility Correlates of Racial Differences in Viral Control for Black and White Veterans with HIV Infection in the Veterans Administration.

Black persons with HIV are less likely than white persons to experience viral control even while in treatment. We sought to understand whether patient characteristics and site of care explain these differences using a cross-sectional analysis of medical records. Our cohort included 8779 black and 7836 white patients in the Veterans Administration (VA) health system with HIV who received antiretroviral medication during 2013. Our primary outcome, viral control, was defined as HIV serum RNA <200 copies/mL. We examined the degree to which racial differences in viral control are related to site of care, patient characteristics (demographics, HIV treatment history, comorbid conditions, time in care, and medication adherence), retention in care, and combination antiretroviral therapy (cART) adherence, using multi-variable logistic regression models. Compared to whites, blacks were younger and had lower CD4 counts, more comorbidities, lower retention in care, and poorer medication adherence. The odds of uncontrolled viral load were 2.02 (p < 0.001) for black relative to white patients without risk adjustment (15% vs. 8% uncontrolled viral load, respectively). The odds decreased to 1.83 (p < 0.001), 1.65 (p < 0.001), 1.62 (p < 0.001), and 1.24 (p = 0.01) in models that sequentially controlled for site of care, age and clinical characteristics, care retention, and cART adherence, respectively. Overall, 51% of the viral control difference between blacks and whites was accounted for by adherence; 26% by site of care. We conclude that differences in the site of HIV care and cART adherence account for most of the difference in viral control between black and white persons receiving HIV care, although the exact pathway by which this relationship occurs is unknown. Targeting poorer performing sites for quality improvement and focusing on improving antiretroviral adherence in black patients may help alleviate disparities in viral control.