Ageing Fast and Slow: A Longitudinal Examination of the Gap Between Subjective Age and Chronological Age and the Role of Functional Health.

Objectives: Although it is known that subjective age is strongly influenced by health, few studies have explored this relation longitudinally. This study aims to examine the longitudinal evolution of the age differential between subjective and chronological age, as well as how functional limitations and birth cohort affect this evolution.

Methods: This study analyses four waves covering 10 years (2004-2014) of the English Longitudinal Study on Ageing, making use of 35,242 observations of 14,219 participants. Using random intercept mixed models in an age vector approach, the difference of the gap between chronological and subjective age is examined over age, conditional on cohort, and subsequently by functional limitations group.

Results: Participants felt, on average, about 9 years younger than their actual age. Subjective ageing happens about a third slower than objective ageing on average. Later-born cohorts feel younger than earlier-born cohorts at a given age. The difference between chronological age and subjective age differs about 8 years between those with and without functional health limitations, but the onset of such functional limitations only decreases the gap with about 1-3 years.

Discussion: This study found that recent cohorts feel younger than older cohorts. The onset of a health limitation represents only about half of the subjective age effect. This illustrates there are large selection effects into the group of people to whom health limitations occur, with people already feeling less young before the actual event occurrence.