Trends and disparities in antiretroviral therapy prescription rates among US Medicare beneficiaries with HIV

Objective: Our objective was to evaluate antiretroviral therapy (ART) prescription rates over time among US Medicare enrolees with HIV and to describe disparities in ART prescription and associated factors. Method: We constructed successive cross-sectional cohorts including adult enrollees with HIV and fee-for-service coverage and Part D enrolment in US Medicare between 2007 and 2019. We calculated the percentage of receipt of any ART prescription (ART%) in a calendar year by sex, age, and original Medicare entitlement and calculated age–sex standardized ART% over time. We used multivariable logistic regression to assess the association between ART prescription and sociodemographic factors and chronic conditions by age strata (<65, ≥65 years) in 2019. Results: ART% increased over time and was highest among people with HIV aged 50–64 years in 2019: 95% in males and 92% in females. Multivariable analysis showed that female sex was associated with less ART%, with odds ratios (ORs) of 0.65 (95% confidence interval [CI] 0.60–0.70) and 0.34 (95% CI 0.30–0.39), than male sex in those aged <65 and ≥65 years, respectively. The youngest and oldest enrollees had lower ART use (e.g., OR 0.43 [95% CI 0.34–0.54] for 18–29 vs. 50–64 years; OR 0.34 [95% CI 0.30–0.39] for ≥80 vs. 65–69 years). The top conditions associated with less ART included dementia and alcohol use disorder. Other factors included no Part D low-income subsidy, non-Hispanic white race, and Midwest residence. Conclusions: ART use increased over time in US Medicare enrollees. Non-Hispanic white, female, and the youngest and oldest enrollees received less ART. Multimorbidity, substance use, and dementia were associated with less ART use. Research to overcome these disparities is needed.