Social support and subsequent cognitive frailty during a 1-year follow-up of older people: the mediating role of psychological distress

Background Frailty and cognitive impairment are two common geriatric symptoms linking adverse health-related outcomes. However, cognitive frailty, a new definition defined by an international consensus group, has been shown to be a better predictor of increased disability, mortality, and other adverse health outcomes among older people than just frailty or cognitive impairment. This study estimated the prospective association between social support and subsequent cognitive frailty over 1 year follow-up, and whether psychological distress mediated the association. Methods The data was drawn from a prospective repeated-measures cohort study on a sample of participants aged 60 and over. A total of 2785 older people who participated in both of the baseline and 1-year follow-up survey were included for the analysis. Cognitive frailty was measured by the coexistence of physical frailty and cognitive impairment without dementia. Control variables included sex, age, education, marital status, economic status, smoking status, alcohol drinking status, chronic conditions, and functional disability. Path analyses with logistic function were performed to examine the direct effects of social support (predictors) on subsequent cognitive frailty (outcome) at 1-year follow-up and the mediating role of psychological distress (mediator) in this link. Results After adjusting for covariates and prior cognitive frailty status, social support was negatively associated with psychological distress (beta = - 0.098, 95% CI = - 0.137 to - 0.066, P < 0.001) and was negatively associated with the log-odds of cognitive frailty (beta = - 0.040, 95% CI = - 0.064 to - 0.016, P < 0.001). The magnitude of mediation effects from social support to cognitive frailty via psychological distress was a*b = - 0.009, and the ratio of a*b/(a*b + c') was 24.32%. Conclusions Lower social support is associated with increased rates of subsequent cognitive frailty over 1-year follow-up, and this link is partially mediated through psychological distress, suggesting that assessing and intervening psychological distress and social support may have important implications for preventing cognitive frailty among older people.