Alterações antropométricas e bioelétricas em decorrência da sarcopenia em idosos: International Mobility in Aging Study IMIAS Brasil

Abstract

Sarcopenia is a syndrome characterized by reduced muscle mass, muscle strength, and physical performance. It is considered one of the principal causes of disability in older adults, which implies impairments in functional capacity and quality of life. There are many factors involved in its geneses, such as decreased protein synthesis, proteolysis, changes in neuromuscular integrity, and fat content. This study evaluated the relationship between sarcopenia and anthropometric and bioelectric parameters in older adults. This study is a cross-sectional nested in a cohort, of the 3rd wave of the International Mobility in the Aging Study - IMIAS Brasil project in 2016, with the participation of 169 older adults. Anthropometric and bioelectric data were collected to assess nutritional status. We used anthropometric data to calculate the body mass index (BMI), and bioelectric data to define the skeletal muscle mass index (MMI). The diagnosis of sarcopenia was obtained using low muscle mass, strength, and physical performance assessment. The bioelectrical impedance vector analysis (BIVA) was used the phase angle (PA). In older adult participants, 14.8% had sarcopenia. Regarding anthropometric nutritional status, 7.1% were thin, and 69.8% were overweight. Older adults with sarcopenia had a lower BMI and arm, calf, and muscle perimeter values than those without these conditions (p<0.05). PA values were lower for men with sarcopenia (p<0.003). In the analysis stratified by sex according to the BIVA, groups of older adults with sarcopenia had longer vectors compared to the others (p<0.0001). When plotting individual vectors, we observed reduced cell mass in 71% of women and 36% of men with sarcopenia. In conclusion, older adults with sarcopenia had lower values of anthropometric parameters regarding muscularity. Also, they had a bioelectric nutritional profile with impaired cellularity.