Longitudinal changes in health related quality of life in Japan based on nationwide surveys and Bayesian regional estimates

要旨

This study aimed to describe chronological changes in health-related quality of life (HRQoL) among Japanese adults. We analyzed data from nationwide questionnaire surveys conducted in FY2017, FY2020, and FY2024, targeting adults aged 20-85 years through a stratified two-stage random sampling method. HRQoL was assessed using EQ-5D-3L instrument. The numbers of valid respondents were 10,204 (34.0%) in FY2017, 8810 (44.1%) in FY2020, and 4,428 (29.5%) in FY2024. For prefecture-level analysis, empirical Bayesian methods (EBM) were applied to stabilize estimates derived from small samples and to examine regional time-series changes. Nationwide mean HRQoL scores were 0.9133 in FY2017, 0.8977 in FY2020, and 0.8834 in FY2024. Compared with FY2017, HRQoL declined significantly in FY2020 and further in FY2024, particularly among male aged 40-69 years and female aged 30-59 years (P < 0.05). EBM analysis confirmed trends across nearly all prefecture. HRQoL in Japan has declined over the past seven years, most notably among middle-aged and older adults. The use of repeated nationwide random sampling enabled robust assessment of longitudinal changes in HRQoL, while empirical Bayesian estimation effectively compensated for the instability arising from small sample sizes in some prefectures, allowing reliable comparisons over time.

主題