Determinants of limitations in activities of daily living among community-dwelling persons aged 80 years and older: Longitudinal national evidence from the Health, Aging and Retirement in Thailand study, 2015–2022

Aim: Few studies have longitudinally assessed the determinants of limitations in activities of daily living (LADL) among persons aged ≥80 years. The aim of this study was to estimate the determinants of LADL among persons aged ≥80 years based on 4-wave national longitudinal data from Thailand. Methods: Data from the Health, Aging and Retirement in Thailand study from 2015, 2017, 2020 and 2022 were utilized. The sample was restricted to community-dwelling persons aged ≥80 years (analytic sample: n = 3113 observations). For the pooled sample, the average age was 85.4 years (range 80–117 years). Established measurements were used to assess LADL. Linear fixed effects regression was applied to assess the time-varying determinants and outcomes. Results: Linear fixed effects regressions showed that increasing age, an increase in the number of chronic conditions, an increase in depressive symptoms, higher religious involvement and being underweight increased LADL, whereas increases in exercise frequency and increases in subjective life expectancy decreased LADL. In addition, in subgroup analysis among 60–79-year-olds, transitioning to widowhood and work status decreased LADL. Further differences between ≥80-year-olds and 60–79-year-olds include that an increase in depressive symptoms and increase in chronic conditions only increased LADL among ≥80-year-olds and not among 60–79-year-olds. Conclusions: This longitudinal study enhances our understanding of the determinants of LADL among persons aged ≥80 years. Strategies to delay or decrease depressive symptoms and chronic conditions, proper weight management and increasing physical activity might help in reducing LADL. Geriatr Gerontol Int 2025; 25: 403–410.