Is 70 the new 60? A longitudinal analysis of cohort trends inintrinsic capacity in England and China

Abstract

To understand how the health of older adults today compares to that of previous generations, we estimated intrinsic capacity and subdomains of cognitive, locomotor, sensory, psychological and vitality capacities in participants of the English Longitudinal Study on Ageing (ELSA) and the China Health and Retirement Longitudinal Study (CHARLS). We applied multilevel growth curve models to examine change over time and cohort trends. We found that more recent cohorts entered older ages with higher levels of capacity, and their subsequent age-related declines were somewhat compressed compared to earlier cohorts. These improvements in capacity were large, with the greatest gains being in the most recent cohorts. For example, a 68-year-old ELSA participant born in 1950 had higher capacity than a 62-year-old born just 10 years earlier. Trends were similar for men and women, and findings were generally consistent across English and Chinese cohorts.

Figure 1

Intrinsic capacity and subdomains mean factor scores by birth cohort and age in ELSA (main analyses). Note: Longitudinal individual weights were used for multilevel growth curve models to ensure representativeness to participants aged 50+ and living in England in 2002 who were still alive and residing in private households by wave 9. The point estimates and their 95% confidence intervals are displayed in the graph.

Figure 2

Intrinsic capacity and subdomains mean factor scores by birth cohort and age in CHARLS (comparative analyses). Note: Survey weights were used to ensure representativeness to participants aged 50+ and living in China. Here we displayed the point estimates and their 95% confidence intervals from the multilevel growth curve models.