Mudança na força muscular de idosos não institucionalizados do sul do Brasil em um período de até seis anos

Abstract

Loss of muscle strength, or dynapenia, has several consequences for the health and quality of life of older adults. Muscle strength is not only an important component of health and physical performance, but also fundamental to performing activities of daily living and is considered an indicator of overall health. Our objective was to evaluate the change in muscle strength in non-institutionalized older adults living in the city of Pelotas/RS over a period of up to six years, as well as to evaluate the change in the occurrence of dynapenia among the participants and to identify possible associated factors. This is an observational study with a longitudinal design, conducted in southern Brazil with participants from the "COMO VAI?" – Consórcio de Mestrado Orientado para Valorização da Atenção ao Idoso (Master’s Consortium Oriented for the Appreciation of Older Adults Care). Data collected at baseline in 2014 and at follow-up in 2019/20 were used. Muscle strength was assessed at both visits using the Jamar® digital handheld dynamometer. Six alternating measurements were taken, three in each hand, with the highest handgrip strength measurement used. Dynapenia was assessed according to the cut-off points of <29.7 kg for men and <16.2 kg for women, considering values below -2.5 standard deviations from the mean of the local young population, as recommended by the second consensus of the European Working Group on Sarcopenia in Older People (EWGSOP2). Descriptive analyses of the sample were performed, and adjusted mixed linear and logistic models were used to assess the change between time periods and the factors associated with the change in muscle strength, considering the repetition of the outcome measures. A total of 483 older adults completed the handgrip strength tests at both visits. In men, muscle strength decreased from 38.2 kg in 2014 to 35.9 kg in 2019-20, while in women it decreased from 23.5 kg to 22.1 kg. Older age (p=0.003), black, brown, or yellow skin color (p=0.005), middle socioeconomic status (p=0.021), and schooling <8 years (p<0.001) were associated with greater decreases in muscle strength. The prevalence of dynapenia increased from 17.8% in 2014 to 24.0% in 2019-20 in men and from 11.3% to 17.5% in women. The changes in dynapenia did not differ between the subgroups of variables studied. As expected, our study showed a decline in muscle strength and an increase in the prevalence of dynapenia over a period of up to six years among the older adults studied. Our results suggest that the variation in muscle strength over time was strongly associated with socioeconomic and demographic factors. Such data will be useful in developing public policies and health programs aimed at maintaining muscle strength at this stage of life. This volume contains the research project, followed by the fieldwork report, the modifications made to the research project, the original article, and the instructions of The Journals of Gerontology: Series A - Oxford Academic to which the article is submitted.