Scientific Reports · Oct 19, 2026
Active ageing across the retirement transition in Korea: regional trajectories and risk of low active ageing
By Lee GM, Cho HK, Hong JW et al.
Retirement may reshape health, participation, and security in later life. Because service access and community resources may differ by region, this study examined whether Active Ageing Index (AAI) trajectories across retirement differed by metropolitan versus non-metropolitan residence among Korean older adults experiencing retirement, and whether predictors of transition to low active ageing differed by region. Five biennial waves (2014–2022) of the Korean Longitudinal Study of Aging were analyzed. Retirees were identified, and regional groups were balanced at the retirement wave using propensity score matching. Event-aligned AAI trajectories were examined using piecewise generalized estimating equation (GEE) models with region-by-time interactions. Cox models examined transition to low AAI and tested interactions between region and individual characteristics. Models adjusted for gender, age, education, marital status, smoking, drinking, and physical activity. AAI was lower at the retirement wave than at the pre-retirement wave, whereas the post-retirement slope was not significant. This retirement-wave difference was attenuated and no longer statistically significant after excluding labor force participation from the AAI participation domain. Region-by-time interactions and region-by-predictor interactions were not statistically significant. Age ≥ 75 years was associated with higher risk of transition to low AAI, whereas physical activity was associated with lower risk. Among Korean retirees, regional differences in AAI trajectories and predictors of transition to low AAI were not statistically significant under the metropolitan/non-metropolitan classification. The retirement-wave decline in total AAI was attenuated after excluding labor force participation from the AAI participation domain. Older age, physical inactivity, and post-retirement participation-related changes may be more closely related to low active ageing after retirement than the broad regional classification used in this study.