Costs and resource use of community-dwelling patients with Alzheimer's disease in Japan: 18-month results from the GERAS-J study

Objective To determine the longitudinal societal costs and burden of community-dwelling patients with Alzheimer's disease (AD) and their caregivers in Japan. Methods GERAS-J was an 18-month, prospective, longitudinal, observational study. Using the Mini-Mental State Examination (MMSE), patients routinely visiting memory clinics were stratified into groups based on AD severity at baseline (mild, moderate, and moderately severe/severe [MS/S]). Healthcare resource utilization and caregiver burden were assessed using the Resource Utilization in Dementia and Zarit "Caregiver" Burden Interview questionnaires, respectively. Total monthly societal costs were estimated using Japan-specific unit costs of services and products (patient direct healthcare use, patient social care use, and informal caregiving time). Results Overall, 553 patients (156 mild; 209 moderate; 188 MS/S) were enrolled. MMSE scores declined (1.73, 1.38, and 0.95 points for the mild, moderate, and MS/S AD groups, respectively) and caregiver burden and resource utilization increased over 18 months in each of the AD severity groups. Cumulative total societal costs per patient over 18 months were 3.1, 3.8, and 5.3 million Japanese yen (29,006, 35,662, and 49,725 USD) for mild, moderate, and MS/S AD, respectively. Both patient social care costs and caregiver informal care costs increased with baseline disease severity, with >50% of total costs due to caregiver informal care in each disease severity subgroup. Conclusions Total treatment costs increased with AD severity over 18 months due to increases in both patient social care costs and caregiver informal care costs. Our data suggest current social care services in Japan are insufficient to alleviate the negative impact of AD on caregiver burden.