Determination of factors affecting exercise capacity in community-dwelling elderly people.

Abstract

Exercise capacity declines with age. However, the effect of common geriatric symptoms, that are related to physical performance, on exercise capacity is unclear. The study aimed to determine the impacts of sarcopenia, frailty, balance, and depression on both overall and abnormal exercise capacity. One hundred and nineteen community-dwelling older adults over 65 years of age were included in the cross-sectional study. Sarcopenia and frailty status were determined according to the "European Working Group on Sarcopenia in Older People2" and "Fried frailty criteria", respectively. Exercise capacity, balance and depression were assessed with the 6-min walk test (6MWT), the Timed Up and Go Test (TUG) and the Geriatric Depression Scale (GDS), respectively. Of the participants, 5% were sarcopenic, 32.8% were frail, and 29.4% had abnormal exercise capacity (6MWT < 82% pred). According to multivariate linear regression analysis, the model consisting of sarcopenia, frailty, TUG and GDS was explained 53% of the variation in 6MWT (R = 0.73, R2 = 0.53, p < 0.001), and all variables except GDS were independent predictors of exercise capacity (p < 0.05). Sarcopenia was the strongest predictor of 6MWT (β =-79.76, p = 0.011). The model including sarcopenia, TUG, frailty, and GDS provided 29% prediction of abnormal exercise capacity (Nagelkerke R2 = 29.7, p < 0.001), while TUG was the sole significant predictor in the model (Odd Ratio:1.32, p < 0.002), according to logistic regression analysis. This study indicates that changes in exercise capacity are more influenced by the presence of sarcopenia, and that poor TUG performance is the greatest risk factor for the impaired exercise capacity.