Trajectories of physical function, depressive symptoms, and cognitive performance before and after falls in older adults: A matched multicohort study

BACKGROUND: Impairments in physical, psychological, and cognitive functioning are associated with an increased risk of falls. However, how these functional domains change longitudinally before and after fall events remains unclear. We examined individual and joint trajectories of these outcomes preceding and following falls. METHODS AND FINDINGS: Using data collected between 2010 and 2021 from three national cohorts in China, the UK, and the USA, we included 28,773 adults aged ≥60 years and performed 1:1 matching between participants who reported falls during follow-up and those who did not. Physical function, depressive symptoms, and cognitive performance were assessed repeatedly using measures of activities of daily living, standardized depression scales, and cognitive test performance, respectively. Falls were self-reported, and fall-related characteristics were evaluated by the need for medical attention, the number of falls, and hip fracture. Statistical analyses included piecewise linear mixed-effects models and group-based multi-trajectory models, with adjustment for age, sex, cohort, socioeconomic status, lifestyle factors, sensory function, and major chronic conditions. A total of 10,990 matched participants who experienced falls and those who did not were included (5,495:5,495; mean age 71.0 [SD 7.2]; 5,010 women and 5,980 men). Compared with participants who did not experience falls, those who experienced falls had poorer physical function, more severe depressive symptoms, and poorer cognitive performance at the time of the fall; these differences were apparent up to 5 years before a fall event and persisted thereafter. Participants who experienced falls also exhibited faster worsening of physical function both before (βfall * pre-time -0.116, 95% CI [-0.142, -0.089]) and after the fall event (βfall * post-time -0.039, 95% CI [-0.050, -0.028]). Faster worsening of depressive symptoms was observed only before the fall event (βfall * pre-time -0.018, 95% CI [-0.026, -0.011]), whereas faster decline in cognitive performance was observed only thereafter (βfall * post-time -0.008, 95% CI [-0.016, 0.000]). In joint trajectory analyses, participants who experienced falls were more likely to experience progressive multidomain functional decline, with the highest odds ratio (2.45, 95% CI [1.97, 3.05]) observed for concurrent worsening across all three domains. Associations were stronger among participants who experienced more severe falls. The main limitations of this study were the reliance on self-reported falls and some functional measures, and the observational design, which precluded causal inference. CONCLUSIONS: In older adults, multidomain functional decline appears to precede falls by several years and worsens further after fall events. Falls may therefore signal broader functional deterioration and highlight the need for prevention and management strategies addressing physical, psychological, and cognitive domains.