The height and weight of patients were measured by the same trained group. The body mass index (BMI) was calculated as the weight in kilograms divided by the height in meters squared. In our previous study, serum irisin levels were accurately measured using a highly quantitative enzyme-linked immunosorbent assay (ELISA) kit from Phoenix Pharmaceuticals Science, Inc. (Burlingame, CA, USA). An automated ELISA reader was used to quantify the results (Varioskan Flash Spectral Scanning Multimode Reader; Thermo Fisher Scientific, Waltham, MA, USA). Irisin levels in the two measurements were consistent.23 (link) Therefore, in the present study, serum irisin levels were measured using an ELISA kit. CHOL, HDL-C, LDL-C, TG, CK, and FPG levels were measured using the Dade-Behring Dimension RXL Autoanalyzer (Siemens Healthcare Diagnostics, Marburg, Germany). The reference intervals for CHOL, HDL-C, LDL-C, TG, CK, and FPG were 3.62 to 5.70 mmol/L, 1.03 to 1.55 mmol/L, 1.81 to 3.36 mmol/L, 0.56 to 2.26 mmol/L, 38 to 174 U/L, and 3.3 to 6.1 mmol/L, respectively. FT3, FT4, and TSH levels were measured by an electrochemiluminescence immunoassay technique using the Abbott Architect i2000 (Abbott Diagnostics, Abbott Park, IL, USA). The reference intervals for FT3, FT4, and TSH were 1.71 to 3.71 pg/mL, 0.70 to 1.48 ng/dL, and 0.35 to 4.94 µIU/mL, respectively.