Cohort differences in trajectories of life satisfaction among Japanese older adults.

Abstract

Individual development and aging are shaped by historical changes in sociocultural contexts. Studies indicate that later-born cohorts experience improvements in well-being in the young–old. However, whether this historical trend holds in the old–old remains unknown. Using longitudinal data of Japanese older adults, we examined birth cohort differences in trajectories of well-being as measured by life satisfaction. Data were derived from a nationally representative study conducted from 1987 to 2012. We compared earlier- and later-born cohorts over 10 years in two age groups: the young–old (n = 1,195 per cohort; age 63–74; years of birth: 1913–1924 and 1925–1936) and the old–old (n = 436 per cohort; age 75–86; years of birth: 1901–1912 and 1913–1924). To control for covariates, we used case-matched cohorts based on age and sex. Growth curve models were employed to estimate age-related changes in life satisfaction by age group. At age 75 years, life satisfaction was higher in the later-born cohort than in the earlier-born cohort across age groups. Cohort differences in the rate of change in life satisfaction were absent among the young–old. Among the old–old, the later-born cohort showed steeper declines than the earlier-born cohort. Socioeconomic, social, and health resources did not fully explain the cohort differences in both age groups. Our results suggest that historical improvements in well-being in the young–old do not persist into the old–old. Societal advancements may enable later-born cohorts to survive with limited resources.