RBP4 and diabetes mellitus: The correlation of RBP4 with TSH (r = 0.241; P = 0.004) and T3 (r = -0.158; P = 0.018) remained significant even after adjustments for potential confounders including age, sex, smoking, hypertension, diabetes, BMI, and the levels of Cr, FBG, TC, TG, HDL-C, and LDL-C.