Impact of the Severity of Alzheimer’s Disease on the Quality of Life, Activities of Daily Living, and Caregiving Costs for Institutionalized Patients on Anti-Alzheimer Medications in Japan

BACKGROUND: Alzheimer’s disease (AD) increases societal costs and decreases the activities of daily living (ADL) and quality of life (QoL) of the affected individuals. OBJECTIVE: We assess the impact of AD severity on ADL, QoL, and caregiving costs in Japanese facilities for the elderly. METHODS: Patients with AD in facilities for the elderly were included (47 facilities, N = 3,461). The QoL, ADL, and disease severity of patients were assessed using Barthel Index (BI), EuroQoL-5D-5L (EQ-5D-5L), and Mini-Mental State Examination (MMSE), respectively. Annual caregiving costs were estimated using patients’ claims data. The patients were subcategorized into the following three groups according to the MMSE score: mild (21≤MMSE≤30), moderate (11≤MMSE≤20), and severe (0≤MMSE≤10). Changes among the three groups were evaluated using the Jonckheere-Terpstra test. RESULTS: Four hundred and one participants were on anti-AD medicines, of whom 287 (age: 86.1±6.4 years, 76.7% women) in the mild (n = 53, 84.0±6.9 years, 71.7%), moderate (n = 118, 86.6±5.9 years, 76.3%), and severe (n = 116, 86.6±6.5 years, 79.3%) groups completed the study questionnaires. The mean BI and EQ-5D-5L scores for each group were 83.6, 65.1, and 32.8 and 0.801, 0.662, and 0.436, respectively. The mean annual caregiving costs were 2.111, 2.470, and 2.809 million JPY, respectively. As AD worsened, the BI and EQ-5D-5L scores decreased and annual caregiving costs increased significantly. CONCLUSION: AD severity has an impact on QoL, ADL, and caregiving costs.