Sex-specific associations between DXA-derived arms fat-to-lean ratio and sarcopenia in Taiwanese patients with type 2 diabetes: a cross-sectional study

Abstract

Sarcopenia is an underrecognized yet clinically significant complication in individuals with type 2 diabetes mellitus (T2DM), influenced in part by adverse alterations in body composition such as myosteatosis. This study examined sex-specific associations between regional fat-to-lean ratios, measured by dual-energy X-ray absorptiometry (DXA), and sarcopenia status in Taiwanese adults with T2DM. A cross-sectional study was conducted in 103 adults with T2DM (60 females, 43 males) aged 50–80 years. DXA quantified regional body composition, including appendicular skeletal muscle mass and regional fat mass. Dominant handgrip strength was assessed using a dynamometer. Sex-specific associations between sarcopenia and regional fat-to-lean ratios were analyzed using Spearman rank-order correlations and multivariable Firth penalized logistic regression models. Sarcopenia prevalence was 15.0% (n = 9/60) in females and 23.3% (n = 10/43) in males. Males exhibited higher lean mass, bone mineral content, and grip strength, whereas females had higher total body fat and fat-to-lean ratios. In males, arms and legs fat-to-lean ratios showed strong, body mass index (BMI)-independent correlations with sarcopenia ( r  = 0.526 and r  = 0.467, respectively; both p  < 0.01). Multivariable Firth penalized logistic regression identified BMI as an independent factor inversely associated with sarcopenia odds in both sexes. Conversely, the arms fat-to-lean ratio (Z-score) emerged as an independent correlate specifically associated with higher odds of sarcopenia in males (OR: 14.183, 95% CI: 2.261–200.137, p  = 0.002). Based on an illustrative mathematical translation, a 0.1-standard deviation increase in this ratio (equivalent to approximately 65 g of additional arm fat) was associated with a 30.4% increase in the odds of sarcopenia. Patients with T2DM demonstrate distinct sex-specific patterns in body composition associated with sarcopenia. The DXA-derived arms fat-to-lean ratio may represent an accessible, BMI-independent clinical surrogate marker to aid in identifying men with T2DM with higher odds of sarcopenia, underscoring the importance of regional body composition assessment in diabetes care.