Association between muscle mass and adipo-metabolic profile: a cross-sectional study in older subjects

Abstract

Background: Sarcopenia, the decrease in muscle mass and function, may lead to various negative health outcomes in elderly. The association among sarcopenia with adiposity and metabolic markers has rarely been studied in the elderly population, with controversial results. The aim of this study is to evaluate this relationship in older subjects.

Methods: A cross-sectional study was conducted in 290 elderly patients, focusing on the possible association between muscle mass loss, assessed by relative skeletal muscle mass (RSMM), and an adipo-metabolic profile (AMP) defined by adiposity and metabolic biochemical markers. Measurements of body composition were assessed by dual energy X-ray absorptiometry. Biochemical parameters, such as albumin, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, total cholesterol, triglycerides, C-reactive protein, and homocysteine and its related markers (folate and vitamin B12) were measured. Using canonical correlation analysis and structural equation modeling, an individual score of AMP was created and correlated with RSMM.

Results: The AMP-RSMM correlation was equal to +0.642 (95% confidence interval, +0.512 to +0.773; P<0.001). Hence, a negative association between sarcopenia severity and adiposity/metabolic biochemical markers was highlighted.

Conclusion: This study contained a novel way to examine the relationship between the variables of interest based on a composite index of adiposity and metabolic conditions. Results shed light on the orientation and magnitude of adiposity and metabolic markers in preventing muscle mass loss. There might be a protective effect of adiposity, compatible with the "obesity paradox."

Keywords: dual energy X-ray absorptiometry; elderly; metabolic risk markers; muscle mass loss.

Figure 1

Scatterplot of the AMP and RSMM index (correlation=r =0.642). AMP is a composite variable defined by averaging the canonical variate pair of DXA and hematochemical indicators. Abbreviations: AMP, adipo-metabolic profile; DXA, dual-energy X-ray absorptiometry; RSMM, relative skeletal muscle mass.