Real-world healthcare resource utilization of Alzheimer's disease in the early and advanced stages: a retrospective cohort study

To compare all-cause and Alzheimer's disease (AD)-related healthcare resource utilization (HCRU) by cognitive stage. This retrospective study analyzed insurance claims data linked to electronic health records (01/01/2015-12/31/2021). Patients with ≥1 cognitive assessment (Mini-Mental State Examination or Montreal Cognitive Assessment) and ≥1 medical or pharmacy claim for an AD diagnosis or AD medications were included. Inverse probability of treatment weighting (IPTW) was used to address potential confounding. All-cause and AD-related HCRU were summarized per patient per year (PPPY) and compared between early AD and advanced AD cohorts (defined according to cognitive scores) using generalized linear regression models; adjusted incidence rate ratios (IRRs), and 95% confidence intervals (CI) were reported. A total of 193 patients were included (median age: 82 years; 63.2% female), 108 with early AD and 85 with advanced AD, with similar mean follow up. All-cause HCRU, on average, was similar between early AD and advanced AD cohorts (37.4 PPPY and 38.9 encounters PPPY, respectively). For AD-related HCRU, patients with early AD had fewer encounters PPPY, on average, than patients with advanced AD (1.26 and 3.88 encounters, respectively). Following IPTW adjustment, the advanced AD cohort had significantly higher overall AD-related HCRU (IRR: 3.64 [95% CI: 1.96-6.75],