Low serum Metrnl levels are associated with increased risk of sarcopenia in the older adults

Abstract Purpose Sarcopenia is a geriatric syndrome characterized by progressive loss of muscle mass and function. Meteorin-like (Metrnl) is a secretory protein that has protective effects on skeletal muscle injury. However, the association of Metrnl level with sarcopenia remains unclear. Methods A total of 772 community-dwelling older adults (median age = 76 years), comprising 409 males and 363 females, from both urban and rural areas were enrolled. Serum Metrnl was measured by enzyme-linked immunosorbent assay. Appendicular skeletal muscle mass index (ASMI), grip strength, and gait speed were measured for the assessment of sarcopenia. Results We found that serum Metrnl levels were lower in patients with sarcopenia [median (IQR) = 180.1 (151.3–220.3) pg/mL] than older adults without sarcopenia [211.9 (163.2–270.0) pg/mL, P < 0.001]. Receiver-operating characteristic curve analysis showed that the optimal cut-off value of serum Metrnl level that predicted sarcopenia was 197.2 pg/mL with a sensitivity of 59.2% and a specificity of 63.8% (AUC = 0.63, 95% CI = 0.59–0.67, P < 0.001). Multivariate logistic regression analyses showed that lower serum Metrnl level (< 197.2 pg/mL) was significantly associated with increased risk of sarcopenia (adjusted OR = 2.358, 2.36, 95% CI = 1.528–3.685, P < 0.001). Moreover, serum Metrnl concentration was positively correlated with the components of sarcopenia including ASMI ( r = 0.135, P < 0.001), grip strength ( r = 0.102, P = 0.005), and gait speed ( r = 0.106, P = 0.003). Conclusions Taken together, our findings demonstrate that low serum Metrnl level is correlated with increased risk of sarcopenia in the older adults.