The old, old-old, and the oldest old: continuation or distinct categories? An examination of the relationship between age and changes in health, function, and wellbeing.

This study aims to examine whether old age, old-old age, and oldest-old age comprise distinct categories via comparing persons aged 75-84, 85-94, and 95+ on demographics, health, function, and wellbeing. The sample was drawn from a representative longitudinal cohort of older persons in Israel. Matched cohort comparisons found a significant decline in Activities of Daily Living (ADL), instrumental ADL, cognitive function, percent of participants who go outside their home, and physical activity, with an increase in physical and mobility difficulties, and no difference in depressed affect or loneliness. Longitudinal results showed increased widowhood, institutionalization, comorbidity, physical and mobility difficulties, loneliness, and depressed affect, as well as decreased subjective health and physical activity over time. In the absence of changes in social support as manifested by marital status and community living, there was no decline in wellbeing. Current evidence of various gradual quantitative differences suggest that in most respects old age may be better conceptualized as a single phase marked by a continual quality.