Associations between the triglyceride‒glucose index and the odds of low muscle mass and sarcopenia: a systematic review and meta-analysis

Sarcopenia, the age-related loss of muscle mass and function, is a public health concern linked to insulin resistance (IR). The triglyceride‒glucose (TyG) index, a marker of IR, may reflect a decrease in muscle health. This meta-analysis, which adhered to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines, reviewed studies from electronic databases investigating the association between the TyG index and low muscle mass or sarcopenia. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated via a random effects model. Twenty cross-sectional studies involving 521,778 participants were included. A higher TyG index was associated with higher odds of low muscle mass (OR = 1.28; 95% CI: 1.10–1.50) and sarcopenia (OR = 1.63; 95% CI: 1.29–2.07). Dose‒response analysis revealed that for every 1-unit increase in the TyG index, the odds of low muscle mass were 1.79 times higher (OR = 1.79; 95% CI: 1.60–2.00). The TyG index is linked to higher odds of low muscle mass and sarcopenia, highlighting its potential as a screening tool. However, due to the cross-sectional design of the included studies, causal relationships cannot be inferred. Longitudinal studies are needed to establish causality. Not applicable.