ABSTRACT
BACKGROUND: At a time when the world's population is aging, one of the most important challenges for the healthcare field is to control the decline of the musculoskeletal system. This decline consists of a reduction in muscle mass and function, which is called sarcopenia and is associated with adverse health outcomes. Although there has been an increase in the number of publications on sarcopenia and its consequences, the reported prevalence varies widely, since these depend on the characteristics of the population studied, the definitions found in the literature and the cut-off points adopted. In this perspective, the heterogeneity in the classification and the different reference values has a critical impact on the epidemiology of sarcopenia, since neither the procedures, the components and the cut-off points are consistent. OBJECTIVES: To develop cut-off points for the screening of sarcopenia in community-dwelling older people residents in the northeast of Brazil and compare the prevalences between the values defined by the consensus and the values of the population studied. METHODS: Community-dwelling older men and women living in three cities in the countryside of Rio Grande do Norte were evaluated. Cutoff points were defined for the variables used to screen for sarcopenia (handgrip strength, SMI, gait speed and SPPB) using the 20th percentile of their population distributions. RESULTS: The sample was composed of 1,290 older people (62.5% female and 37.5% male), with an average of 69.5 (± 6.05) years of age. Regarding the cutoff points, the handgrip values were defined as 25.3 kg and 16 kg for men and women, respectively. Considering the SMM adjusted according to their height, the values of 7.88 kg/m2 were adopted for men and 5.52 kg/m2 for women. When adjusting by BMI we obtained 0.73 kg/BMI for men and 0.41 kg/BMI for women. For gait speed it was defined 0.71 m/s for men and 0.63 m/s for women. In the case of SPPB, the result was the same for both genders (≤8). When applying the values found in the studied population, a variation in prevalence was observed for both men and women, depending on the cut-off points and consensus used. CONCLUSION: The cutoff values found in our population were lower than those adopted by international consensus (EWGSOP2, IWGS and FNIH), except for HGS in woman and SMI/m2 for men. Therefore, using specific cutoff points for different populations can provide an accurate assessment of the presence of sarcopenia and better target health prevention strategies for the older people living in the community.
ABSTRACT
BACKGROUND: The reduction of female sex hormones causes changes in the contractile properties of muscles as well as infiltration of fat in the muscle tissue. This results in a consequent decline in muscle strength. These changes are related to higher levels of functional impairment and physical disability. In this sense, several anthropometric indices have been used to quantify body and visceral fat. Thus, the objective of this paper is to propose cutoff points for adiposity anthropometric indices in order to identify low muscle mass, as well as to analyze the relationship between these indices and low muscle mass in middle-aged and older women. METHODS: Cross-sectional analytical study carried out in the Northeast of Brazil. The sample was formed by 593 women between 40-80 years old. Data collection included anthropometric assessment (BMI: Body Mass Index - WC: Waist Circumference - WHR: Waist-to-hip Ratio - WHtR: Waist-to-height Ratio - CI: Conicity Index - BAI: Body Adiposity Index - VAI: Visceral Adiposity Index - LAP: Lipid Accumulation Product), bioimpedance test and biochemical dosage. Moreover, sociodemographic data and practice of physical activity were collected. Descriptive statistics, Student's t-test, ROC curves, chi-squared and logistic regression were performed. RESULTS: The participants had a mean age of 53.11 (8.89) years, BMI of 28.49 (5.17) kg/m2 and WC of 95.35 (10.39). The prevalence of low muscle mass was 19.4%. Based on sensitivity and specificity of adiposity anthropometric indices, cutoff points were developed to identify the presence of low muscle mass (p < 0.05), except for VAI. After logistic regression, WC (OR = 6.2; CI 95%: 1.4-28.1), WHR (OR = 1.8; CI: 1.0-3.4), WHtR (OR = 5.0; CI 95%: 1.0-23.7) and BAI (OR = 14.5; CI 95%: 6.6-31.7) were associated with low muscle mass. CONCLUSIONS: All anthropometric indices, except VAI, showed adequate accuracy in identifying low muscle mass in women, especially those that took into account WC. This suggests that they can become accessible and also be cost-effective strategies for assessing and managing health outcomes related to muscle mass analysis.
