Costs associated with increasing numbers of Medicare beneficiaries with HIV aged 65 years and older from 2026 to 2035

ImportanceAs the population of older people with HIV (PWH) in the US is growing, costs to Medicare are expected to rise substantially. ObjectivesTo project the number of Medicare beneficiaries with HIV aged 65y+ on ART in the US from 2026-2035 and the budget impact on Medicare. Design, Setting, and ParticipantsWe developed the novel CHARMED simulation model and projected the number of Medicare beneficiaries with HIV aged 65y+ on ART and associated costs from 2026 to 2035; we populated the model with age and sex-stratified clinical data and costs derived from 2023 Traditional Medicare (TM) claims and accounted for enrollment in Medicare Advantage, as well as healthcare inflation. Main Outcomes and MeasuresNumbers of Medicare beneficiaries with HIV aged 65y+ on ART and undiscounted costs to Medicare from 2026-2035. ResultsWe projected that 111,600 PWH would be enrolled in Medicare and in care at the beginning of 2026 (65-69y: 57,370; 70-74y: 32,940; 75-79y: 14,670; 80y+: 6,610). By the end of 2035, this number would nearly double, to 193,560 (65-69y: 70,490; 70-74y: 62,820; 75-79y: 38,290; 80y+: 21,960). Annual costs to Medicare for PWH 65y+ on ART would increase 2.5-fold, from $11.4 billion at the end of 2026 to $28.6 billion at the end of 2035. Cumulative 10-year costs are projected to be $195.6 billion with 66.5% of cumulative costs due to ART. If ART costs are reduced by 60% as per the Inflation Reduction Act or generic ART, Medicare would save $78.0 billion over the next decade. Conclusions and RelevanceThe number of Medicare beneficiaries with HIV 65y+ on ART will more than double over the next decade, resulting in $195.6 billion in 10-year total costs to Medicare. Reducing ART costs through the IRA or generic oral ART could lead to 40% lower overall Medicare spending for older Medicare beneficiaries with HIV. KEY POINTSO_ST_ABSQuestionC_ST_ABSAs the population of people with HIV in the US grows older, what are the expected costs to Medicare and the impact of antiretroviral therapy (ART) costs? FindingsUsing microsimulation modeling, we find that the number of Medicare beneficiaries with HIV 65y+ on ART will more than double over the next decade. At current costs of ART and health care-associated inflation, total 10-year costs to Medicare are anticipated to be $196.5 billion; reducing ART costs through the Inflation Reduction Act or generic ART could lower Medicare spending by 40%. MeaningEfforts to reduce ART costs, while maintaining access to high-quality ART, are critical to reduce total Medicare costs as more people with HIV are anticipated to enroll in Medicare in the next 10 years.