RESUMO
Objective: To study the extent to which fear of falling (FOF) is associated with the onset of functional disability over a 2-year period in older adults using self-reported and performance-based measures. Methods: In 2012, 1,601 participants (aged 65-74 years) were recruited from four sites: Kingston and Saint-Hyacinthe, Canada; Manizales, Colombia; and Natal, Brazil. They were re-assessed in 2014. We quantified FOF using the Fall Efficacy Scale-International (FES-I; range: 16-64). Functional disability measures were (i) self-reported incident mobility disability, defined as difficulty climbing a flight of stairs or walking 400 m and (ii) incident poor physical performance, defined as a score <9 on the Short Physical Performance Battery. In the Poisson regression analysis, we included only those participants without functional disability at baseline to calculate incident risk ratios in 2014. Results: 1,355 participants completed the 2014 assessment, of which 917 and 1,078 had no mobility disability and poor physical performance at baseline, respectively. In 2014, 131 (14.3%), and 166 (15.4%) participants reported incident mobility disability and poor physical performance, respectively. After adjusting for age, sex, socioeconomic, and health covariates, a one-point increase in FES-I at baseline was significantly associated with a 4% increase in the risk of reporting incident mobility disability (95% CI: 1.02-1.05) and a 3% increase in the risk of developing poor physical performance at follow up in the overall sample (95%CI: 1.01-1.05). Conclusions: FOF is associated with a higher risk of incident mobility disability and poor physical performance in a cohort of older adults. It is increasingly important to study FOF's effect on functional disability and to take necessary measures to prevent the transition to end-stage disability.