INS and type 2 diabetes mellitus: The T2DM patients were not significantly different to the HC group in terms of age, sex, education, BMI, blood pressure, fasting insulin, fasting C-peptide, HOMA2-IR, total cholesterol, low-density lipoprotein (LDL) cholesterol, homocysteine, blood urea nitrogen, serum creatine, cystatin C, uric acid, and thyroid stimulating hormone (p > 0.05).