Trajectories and determinants of ageing in Portugal: insights from EpiDoC, a nationwide population-based cohort

Introduction: The population in Portugal is ageing due to increased life expectancy and reduced fertility rates. We aimed to estimate the health trajectories of Portuguese older adults (60 + years old) in a 10-year period and to assess associated sociodemographic, lifestyle factors and multimorbidity status. Methods: Using the population-based EpiDoC cohort, we estimated the trajectories of health-related quality of life and physical function of 4135 Portuguese older adults over 10 years using linear mixed models. Factors associated to health-related quality of life and physical function were assessed using linear mixed models and random intercept tobit regression, respectively. Results: The physical disability of participants increased by 0.263 (0.240, 0.286), and health-related quality of life declined by 0.074 (-0.084, -0.063), over 10 years. With advancing age, older adults reported a faster reduction in health-related quality of life and faster increase in physical disability. In general, women were in worse health than men at baseline, albeit with a similar rate of change throughout the follow-up. Higher education and regular exercise were associated with better health-related quality of life and physical function while multimorbidity and excess weight were associated with worse reporting of these outcomes. Conclusions: These findings, based on longitudinal data with 10 years of follow-up, are essential to effectively plan resource allocation, plan better healthcare and design informed public health policies in Portugal. Brief summary: This study characterizes ageing in Portugal showing increased physical disability and decreased health-related quality of life with advancing age older adults, helping to develop public health policies.