Total energy expenditure and functional status in the older adults

Introduction: The population of Latin America (LA) is aging faster than the population of developed countries. Higher total energy expenditure in free living conditions, regardless of any activity, has been strongly associated with lower risk of mortality in healthy older adults. Also, good performance in physical and functional tests are markers of good prognosis. However, it is not yet clear what is the association between total energy expenditure, performance in physical and functional tests and habitual physical activity, and which of these tests are associated with energy expenditure. Objective: to evaluate the association between the total energy expenditure measured by doubly labelled water and the functional status of the older adults. Materials and Methods: This is a cross-sectional study, including 56 older people recruited from health services linked to participating institutions. Socio-demographic, anthropometric and clinical characteristics (through the application of a structured questionnaire), as well as the functional status were assessed. The participants were also submitted to dual energy x-ray absorptiometry (DEXA) to assess body composition. Total energy expenditure (GET) was assessed using the doubly labelled water method and the physical activity profile was verified using a self-report questionnaire and an activity monitor based on accelerometry. Results: The results showed that the highest total energy expenditure correlated with the best performance in the gait speed tests (r = 0.266; p = 0.047), 6-minute walk test (r = 0.424; p = 0.001) and maximum handgrip strength (r = 0.478; p = 0.000). Multivariate regression analysis in a model adjusted for sex and fat-free mass revealed an association between total energy expenditure and the 6-minute walk test (ß = 1.790; t = 2.080; p = 0.044) and the number of sedentary events (ß = 6.389; t = 2.147; p = 0.038). Conclusion: The results of this study suggest that, in clinical practice, older individuals with lower gait speed, worse performance in the 6-minute walk test and lower handgrip strength, may have lower total energy expenditure, being the stimulus for its increase important for the prevention of possible problems related to low energy expenditure. (AU)