Socioeconomic Inequality, Physical Functioning, and Functional Independence Among the Oldest-Old: Evidence from the SHARE Survey

Population ageing has led to a rapid increase in the number of individuals aged 80 and above, yet empirical evidence on the determinants of quality of life among the oldest-old remains limited. This study investigates the socioeconomic, lifestyle, and care-related factors associated with functional independence at very advanced ages using harmonized cross-national data from the Survey of Health, Ageing and Retirement in Europe (SHARE). Focusing on individuals aged 80 and above, we estimate logistic regression models to examine the probability of experiencing limitations in activities of daily living (ADL). The results reveal a persistent socioeconomic gradient in functional health: educational attainment is significantly associated with lower odds of ADL limitations, even after controlling for age, gender, physical functioning, living arrangements, and country fixed effects. Preserved physical functioning, proxied by the absence of walking difficulties, emerges as a strong protective factor against functional dependency. By contrast, institutional residence does not exhibit an independent association with ADL limitations once individual characteristics are taken into account. These findings demonstrate that functional independence among the oldest-old reflects long-term life-course resources and lifestyle-related capacities rather than late-life care settings alone. Policies aimed at promoting successful ageing should therefore adopt a life-course perspective, emphasizing education, health literacy, and the maintenance of physical functioning to enhance quality of life at very advanced ages.