GPT and depressive symptom measurement: BMI, body mass index; IIEF-5, international index of erectile function 5; SAS, self-rating anxiety scale; SDS, self-rating depression scale; FPG, fasting plasma glucose; HbA1c, glycated hemoglobin; TC, total cholesterol; TG, triglyceride; TT, testosterone; TSH, thyroid stimulating hormone; Scr, serum creatinine; Urea, carbamide; ALT, alanine aminotransferase; AST, aspartate aminotransferase.