Association among measures of mobility-related disability and self-perceived fatigue among older people: a population-based study

OBJECTIVE: To investigate the relationship between self-perceived fatigue with different physical functioning tests and functional performance scales used for evaluating mobility-related disability among community-dwelling older persons. METHOD: This is a cross-sectional, population-based study. The sample was composed of older persons with 65 years of age or more living in Cuiabá, MT, and Barueri, SP, Brazil. The data for this study is from the FIBRA Network Study. The presence of self-perceived fatigue was assessed using self-reports based on the Center for Epidemiologic Studies-Depression Scale. The Lawton instrumental activities of daily living scale (IADL) and the advanced activities of daily living scale (AADL) were used to assess performance and participation restriction. The following physical functioning tests were used: five-step test (FST), the Short Physical Performance Battery (SPPB), and usual gait speed (UGS). Three models of logistic regression analysis were conducted, and a significance level of α<0.05 was adopted. RESULTS: The sample was composed of 776 older adults with a mean age (SD) of 71.9 (5.9) years, of whom the majority were women (74%). The prevalence of self-perceived fatigue within the participants was 20%. After adjusting for covariates, SPPB, UGS, IADL, and AADL remained associated with self-perceived fatigue in the final multivariate regression model. CONCLUSION: Our results suggest that there is an association between self-perceived fatigue and lower extremity function, usual gait speed and activity limitation and participation restriction in older adults. Further cohort studies are needed to investigate which physical performance measure may be able to predict the negative impact of fatigue in older adults.