A Mendelian randomization study reveals TNF-β as a potential protective factor against sarcopenia

Sarcopenia, defined by the loss of muscle mass and strength, significantly impacts the elderly and is linked to chronic inflammation. The exact causal relationship between circulating inflammatory factors and sarcopenia is not yet clear. We employed a 2-sample Mendelian randomization analysis using 91 circulating inflammatory factors as exposures and 4 sarcopenia traits as outcomes to explore potential causality. Our analysis confirmed a significant causal association between circulating inflammatory factors and sarcopenia. Specifically, tumor necrosis factor-beta was significantly associated with all sarcopenia traits (appendicular lean mass: P < .001, odds ratio [OR] = 1.023; left grip strength: P < .001, OR = 1.010; right grip strength: P = .001, OR = 1.008; walking pace: P = .017, OR = 1.004), supported by Bonferroni correction and multiple sensitivity analyses. Tumor necrosis factor-beta has emerged as a critical protective factor for sarcopenia, suggesting that targeting its levels may influence treatment approaches. This study emphasized the role of inflammatory pathways in sarcopenia and demonstrated the utility of Mendelian randomization in identifying these associations.