Correlação entre o tecido apendicular mole magro avaliado pelo DXA com a força muscular de membros superiores: um estudo transversal

Abstract

Introduction: Sarcopenia is characterized by progressive loss of muscle mass and strength. Therefore, the assessment of muscle quantity and functionality is essential to understand its progression and clinical impact. Indicators such as handgrip strength (HGS) and elbow flexion strength (EFS) are widely used to measure muscle functionality, while lean soft appendicular tissue (LSAT), assessed by dual-energy X-ray absorptiometry (DXA), is the reference standard for measuring a proxy for skeletal muscle mass. Investigating the relationship between these configurations can contribute to more accurate diagnoses and more effective clinical practices. Objective: To correlate LSAT with upper limb muscle strength. Methods: An observational study with cross-sectional data collection was carried out in healthy individuals, in which sociodemographic and clinical data were collected, as well as body composition according to DXA, and strength tests such as HGS and EFS were performed. Muscle strength was measured in the right upper limbs of the participant and maximum forces were used for analysis. The normality of distribution of continuous variables was verified by the Shapiro-Wilk test. To verify the existence of an association between continuous variables, the Spearman correlation test was used. A value of p <0.05 was considered statistically significant for all tests. Results: Regarding the evaluation of muscle strength, the study showed that there were significant differences between the sexes (p <0.001). Men presented higher values ​​compared to women, both in isolated strength (HGS: 36 kg vs 24 kg; EFS: 23 kg vs 13.8 kg) and in combined strength (57.8 kg vs 37.4 kg). The analyses indicated a strong correlation between HGS and LSAT (rho = 0.72), EFS and LSAT (rho = 0.76) and combined strength and LSAT (rho = 0.78), suggesting that the increase in kilograms of these variables is strongly related to the increase in kilograms of LSAT, regardless of sex. Conclusion: The study demonstrated a strong correlation between LSAT, estimated by DXA, and upper limb muscle strength, contributing to the body of existing scientific evidence on this topic and reinforcing the relevance of muscle strength assessment to investigate the relationship between functionality and muscle composition in different contexts, thus collaborating with the improvement of diagnostic tools applicable to clinical practice and scientific research