Enjoyment of life and declining physical function at older ages: a longitudinal cohort study

Background: Positive affective well-being (i.e., feelings of happiness and enjoyment) has been associated with longer survival and reduced incidence of serious illness. Our objective was to discover whether enjoyment of life also predicted a reduced risk of functional impairment over an 8-year period in a large population sample. Methods: We carried out a prospective analysis involving 3199 men and women aged 60 years or older from the English Longitudinal Study of Ageing. Enjoyment of life was assessed by questionnaire. Outcomes were impairment in 2 or more activities of daily living and changes in gait speed on a walking test. Covariates included sociodemographic factors, baseline health, depressive symptoms, impairment of mobility and health behaviours. Results: Two or more impaired activities of daily living developed among 4.4%, 11.7% and 16.8% of participants in the high, medium and low enjoyment-of-life tertiles, respectively. After adjustment for covariates, the odds of impaired activities of daily living developing were 1.83 (95% confidence interval 1.13-2.96) in the low compared with high tertile. Gait speed after 8 years was also related to baseline enjoyment of life after adjustment for gait speed and other covariates at baseline (p < 0.001). We obtained similar results when we limited analyses to participants younger than 70 years at baseline. Interpretation: This is an observational study, so causal conclusions cannot be drawn. But our results provide evidence that reduced enjoyment of life may be related to the future disability and mobility of older people.