Investigating HIV viral suppression rates at varying levels of adherence to antiretroviral therapy within a medical home model

Abstract

ObjectiveTo investigate human immunodeficiency virus (HIV) viral suppression rates at different adherence thresholds. DesignA retrospective analysis of electronic health record data. Setting and participantsThis study took place across 5 HIV medical homes and included 3527 participants. Outcome measuresThe primary outcome was to determine the viral suppression rate for participants with an antiretroviral therapy (ART) proportion of days covered (PDC) ≥90%. Viral suppression rates for participants with less strict PDC ratios (<50, 50 to <80%, 80 to <85%, and 85% to <90%) were compared to those with a PDC ≥ 90% as a secondary outcome. ResultsThe viral suppression rate was 95.8% for participants with a PDC ≥ 90% (N = 2115). Compared to the PDC ≥ 90% group, there was a 50% lower likelihood of viral suppression with a PDC 85 to <90% (N = 336, OR 0.5, 95% CI 0.32 to 0.79), a 74% lower likelihood of viral suppression with a PDC 50 to <80% (N = 587, OR 0.26, 95% CI 0.19 to 0.35), and a 91% lower likelihood of viral suppression with a PDC < 50% (N = 296, OR 0.09, 95% CI 0.06 to 0.12). ConclusionOver 95% of participants on ART with a PDC ≥ 90% had a suppressed HIV viral load. Further research is needed to determine the effect of comorbidities and social determinants on PDC and viral load suppression.