Abstract
BACKGROUND: Persistence to antiretroviral therapy (ART) is essential for optimal HIV treatment outcomes. People with HIV (PWH) enrolled in Medicare often have a higher prevalence of comorbidities, which can negatively impact persistence, leading to suboptimal HIV outcomes. OBJECTIVE: To compare ART switch patterns among PWH insured by Medicare. METHODS: Using Medicare Fee-for-Service and Medicare Advantage claims data from January 2017 to December 2022, a retrospective cohort study of treatment-experienced PWH aged 18 years and older and on ART was conducted. ART regimens included bictegravir/emtricitabine/tenofovir alafenamide (B/F/TAF), dolutegravir/lamivudine (DTG/3TC), dolutegravir/abacavir/lamivudine (DTG/ABC/3TC), or multitablet regimens (MTRs; dolutegravir + emtricitabine/tenofovir alafenamide [DTG + F/TAF] or dolutegravir + emtricitabine/tenofovir disoproxil fumarate [DTG + F/TDF]). An analysis of PWH who had mental health and/or substance use disorders was also conducted. Treatment switch by ART regimen was evaluated using Kaplan-Meier curves, log-rank tests, and Cox proportional hazards models after using inverse probability treatment weighting to balance across groups. RESULTS: A total of 30,205 treatment-experienced PWH were included. PWH who initiated DTG/3TC, DTG/ABC/3TC, and MTRs on the index date had 1.28 (95% CI = 1.13-1.45), 2.67 (95% CI = 2.47-2.89), and 5.37 (95% CI = 4.60-6.26) times higher hazard ratio of switching ART, respectively, compared with PWH indexed on B/F/TAF (all P < 0.0001). Similar results were observed among PWH with mental health and/or substance use disorders. CONCLUSIONS: Medicare-insured PWH indexed on B/F/TAF had lower risk of treatment switch compared with other ART regimens, both overall and in the subgroup with mental health and/or substance use disorders. These findings may inform targeted strategies for optimal treatment selection for PWH.