Demographics, comorbidities, and comedications in newly diagnosed patients with Alzheimer's disease and related dementias: Findings from United States Medicare claims data

Background: Medicare claims data enables broad characterization of United States (US) patients with Alzheimer's disease and related dementias (ADRD). Resulting insights can be used as a reference to describe this population and as a benchmark for generalizability of patients with ADRD enrolled in clinical trials.

Objective: To characterize demographics, comorbidities, comedications, and healthcare resource utilization in US patients with newly diagnosed ADRD, focusing on differences across Medicare fee-for-service (FFS) and Medicare Advantage enrollees.

Methods: This observational cohort study used complete (100%) Medicare claims data inclusive of both FFS and Medicare Advantage insurance types. Study patients were ≥65-years-old with ≥12 months of continuous pre-index enrollment and Medicare Part D coverage. Two cohorts of patients were selected in calendar year 2019; those newly diagnosed with ADRD and those with a new acetylcholinesterase inhibitor (AChEI) claim.

Results: The newly diagnosed ADRD and new AChEI users cohorts included 861,727 and 395,319 patients, respectively. Demographics and comedications were generally similar across the two cohorts, supporting internal validity of the study results. Circulatory system-related comorbidities and mood disorders were common in both cohorts. Differences in race, inpatient claims and long-term care claims were observed between insurance types.

Conclusions: The study results provide a reference for describing the ADRD population in the US and emphasize the importance of evaluating new Alzheimer's disease drugs in broad patient populations with comorbidities and concomitant medication use.