Health care utilization before and after a dementia diagnosis in Medicare Advantage versus traditional Medicare

Abstract

AbstractBackgroundHalf of all Medicare beneficiaries are enrolled in Medicare Advantage (MA). Many studies document lower care utilization and mortality in MA than traditional Medicare (TM), but evidence for persons with Alzheimer's disease and related dementias (ADRD) is limited.MethodsWe conducted a retrospective cohort study of 2015–2018 Medicare claims and encounter data for community‐dwelling beneficiaries aged 65 and over in TM and MA with an incident ADRD diagnosis in 2017. We compared monthly hospitalization rates and outpatient visits 12 months before and after diagnosis and mortality 1 year from diagnosis. Models adjusted for sociodemographic characteristics and comorbidities. Sensitivity analyses addressed residual confounding using a control group with incident arthritis/glaucoma or excluding MA Special Needs Plans, and potential underreporting by restricting to MA plans with high data completeness.ResultsAmong 454,508 beneficiaries diagnosed with ADRD in 2017, 250,837 (55%) were in TM and 203,671 (45%) in MA. Four to 12 months before diagnosis, monthly hospitalizations and outpatient visits were similar in TM and MA. In the diagnosis month, 36.5% of beneficiaries in TM had a hospitalization compared with 25.4% in MA, an adjusted difference of 10.7 percentage points [95% CI: 10.3, 11.1]. Beneficiaries in TM averaged 10.5 outpatient visits in the diagnosis month compared with 8.4 in MA, an adjusted difference of 1.59 visits [95% CI: 1.47–1.70]. Utilization differences narrowed but remained higher in TM for many months. One‐year mortality was 27.9% in TM and 22.2% in MA; an adjusted odds ratio of 1.152 [95% CI: 1.135–1.169] for those in TM compared with MA. Controlling for hospitalization in the diagnosis month substantially reduced the mortality difference.ConclusionHospitalization rates and outpatient visits increased more after an ADRD diagnosis in TM than MA. One‐year post‐diagnosis, mortality was not higher in MA than TM but comparisons of quality of life and caregiver burden are needed.