Obesidade sarcopênica, síndrome metabólica e desempenho físico em mulheres de meia-idade: um estudo transversal

Abstract

Introduction: Population‟s aging associated with increased life expectancy demands chronic diseases to require more attention, particularly those related changes in morph physiological standards. In this sense, sarcopenic obesity and metabolic syndrome are associated with increased cardiovascular risk. However, those conditions have been poorly studied in middle-aged women, particularly in low-income regions such as Northeast Brazil. It is important to consider women in this age group as a vulnerable to metabolic syndrome, seeking their potential risk factors. Furthermore, the relationship of sarcopenic obesity with physical performance is not clear in literature, or their level of impact when compared to sarcopenia or obesity alone. Objectives: 1) To evaluate the prevalence of sarcopenic obesity and to explore the relationship between sarcopenic obesity and physical performance in middle-aged women from Northeast Brazil. 2) To determine the prevalence of metabolic syndrome, and identified factors associated with this syndrome in middle-aged women in Northeast Brazil. Methods: Cross-sectional study in a sample of 500 women between 40 and 65 years living in Parnamirim-RN. We collected demographic and socioeconomic data, anthropometric measurements, menopausal status, reproductive history, lifestyle habits, physical activity, quality of life, body composition (bioimpedance electrical), estradiol hormone and physical performance (grip strength, knee extensor and flexor strength – isometric dynamometry, gait speed and chair stand test). The sarcopenia was determined by the 20th percentile (<6.08 kg/m²) of the sum of appendicular skeletal muscle mass divided by height squared (kg/m2) and obesity by waist circumference ≥ 88 cm. Sarcopenic obesity was defined as the coexistence of sarcopenia and obesity. Metabolic syndrome is considered by the presence of at least three of the following criteria: abdominal obesity (waist circunference > 88 cm), fasting glucose ≥ 110 mg/dL, triglycerides ≥ 150 mg/dL, high density lipoprotein (HDL) < 50 mg/dl and blood pressure ≥ 130/85 mmHg, according to the diagnostic criteria of the NCEP-ATP III. The four groups of women (sarcopenic obese, sarcopenic, obese and normal) were compared to physical performance variables using analysis of variance (ANOVA) and linear regressions adjusted for potential confounders (age, education and menopausal status). To compare means and frequencies of variables between groups of presence or absence of metabolic syndrome t or Chi-square test were used. Finally, multivariate Poisson regression models were conducted to estimate the prevalence ratio and identify associated factors, by the method step by step (stepwise approach). In all tests, it was considered p < 0.05 and confidence intervals of 95%. Results: Prevalence rates of the four obesity-sarcopenia groups were: Sarcopenic obesity (7.1%), obesity (67.4%), sarcopenia (12.4%) and normal (13%) (n = 491). Women with sarcopenic obesity had significantly lower grip strength, weaker knee extension and flexion and longer time to raise from a chair compared with non-obese and non-sarcopenic women (p values < 0.001). Except for the chair stands, these statistically significant differences were also found between sarcopenic obese and obese women. There was no significant difference for gait speed across the four groups (p = 0.50). Regarding metabolic syndrome (n = 419), 275 (65.6%) cases were identified. The three most prevalent indicators were obesity (73.5%), reduced HDL (63.0%), and elevated blood pressure (60.9%). In the final adjusted model, black race (PR: 1.34, CI: 1.11 - 1.63), lower grip strength/BMI (PR: 1.32, CI: 1.15 - 1.50), worse quality of life (PR: 1.20, CI 95%: 1.03 - 1.40), low levels of estradiol (PR: 1.16, CI: 1.00 - 1.34) and surprisingly, more walking (PR: 1.16, CI: 1.01 - 1.34) were significantly associated with metabolic syndrome. Conclusions: Sarcopenic obesity was present in 7.1% of middle-aged women and it was associated with poor physical performance. Sarcopenic obesity may occur in middle-aged women with limitations beyond pure sarcopenia or obesity alone. The prevalence of metabolic syndrome in our sample was high (65,6%) in the present sample. Black race, lower grip strength/BMI, worse quality of life, lower levels of estradiol and more walking were risk factors for metabolic syndrome. Metabolic syndrome and obesity sarcopenic are a long-term threat to the health of middle-aged women with a burden potential for the public health system. The results may help in the development of health promotion strategies to prevent morbidity and mortality associated with these conditions in this vulnerable population.