Trajectories of Accumulation of Health Deficits in Older Adults: Are There Variations According to Health Domains?

Abstract

Objectives: To analyze sex- and education-specific trajectories of health deficits accumulation (DA) throughout old age and to examine whether these trajectories differ according to health domains.

Design: Population-based prospective cohort study.

Setting: and participants: In Spain, 3228 community-dwelling individuals aged 60 years or older were followed up for 10 years.

Measures: At baseline and 3 follow-up visits, a DA index (0 to 100% deficit) was calculated based on the number and severity of 52 health deficits across the domains of physical and cognitive function, self-rated health and vitality, mental health, and morbidity. Trajectories of overall and domain-specific DA indexes were estimated using mixed models for repeated measurements, allowing for homogeneous linear, piecewise linear, and smooth nonlinear DA trends over age.

Results: Women showed greater DA than men, but differences leveled out with age: annual increments in DA index (95% confidence interval) for participants aged <70, 70-80, and ≥80 years were, respectively, 0.40 (0.30-0.50), 0.68 (0.57-0.80), and 1.30 (1.07-1.54) in men and 0.63 (0.53-0.73), 0.99 (0.89-1.10), and 1.31 (1.09-1.53) in women. These changes were mainly driven by a progressive accumulation of chronic diseases and by quadratic declines in physical and cognitive function. Both men and women showed improvements in mental health with age. In general, women and participants with lower education had decreased physical and cognitive function and accumulated morbidities faster than their counterparts. Only individuals with very fast declines in function and fast accumulation of morbidities showed a significant worsening of self-rated health and vitality over time.

Conclusions: Public health interventions aimed at promoting healthy ageing should focus on prevention and early control of chronic diseases, as well on the preservation of function and early rehabilitation, with the latter being more relevant during the latter stages of life. Post-acute and long-term care services should incorporate adequate physical therapy and nursing facilities to promote attainable levels of functionality in older adults.

Keywords: Deficit accumulation; function; healthy ageing; mental health; mixed models; morbidity; repeated measures.