The Association between Sarcopenic Obesity and DXA-Derived Visceral Adipose Tissue (VAT) in Adults

Many people with overweight and obesity are affected by sarcopenia, which is represented by a phenotype known as sarcopenic obesity (SO), characterized by excessive body fat (BF), combined with reduced muscle mass and strength. In this population, it is vital to identify the factors associated with SO. With this aim in mind, we investigated the association between visceral adipose tissue (VAT) mass and SO in patients with overweight or obesity in a nutritional setting. A total of 256 participants (23.8% female) with overweight or obesity were involved and completed a body composition assessment, including VAT mass, using dual-energy X-ray absorptiometry (DXA). The sample was initially categorized according to whether the individual had the SO phenotype; they were then classified according to their VAT mass into three tertiles (lowest, medium, and highest). Among the 256 participants, who had a median body mass index (BMI) of 29.3 (interquartile range (IQR): 27.0-32.4) kg/m² and a median age of 51.0 (IQR: 47.0-54.0) years, 32.4% were identified as having SO, and they displayed a higher median VAT mass (517.0 (IQR: 384.5-677.0) vs. 790.0 (IQR: 654.0-1007.0) g; p < 0.05). The logistic regression model that accounted for age, sex and BMI revealed that a higher VAT mass increases the risk of SO (odds ratio (OR) = 1.003; 95% confidence interval (CI): 1.001-1.004; p < 0.05). In conclusion, VAT mass appears to be an independent factor associated with SO in people with overweight or obesity. However, due to the cross-sectional design, no information regarding any causality between higher VAT mass and SO can be provided. Additional longitudinal research in this direction should therefore be conducted.