SIRT1 and musculoskeletal system disorder: Specifically, in the musculoskeletal disorders group, the SIRT1 concentration in the case group was 1.72 ng/mL higher than in the control group (WMD, 1.72 ng/mL; 95% CI 1.37, 2.06 ng/mL; P< 0.001; I2 = 95.1%).