GPT and diabetes mellitus: Among the subjects included in the longitudinal analyses, the mean values of the BMI, waist circumstance, fasting blood glucose, TG, AST, ALT, GGT, the prevalence of being overweight, diabetes and dyslipidemia were significantly higher in the NAFLD subjects than in the non-NAFLD subjects at baseline, whereas the value of HDL-C was significantly lower (Table 1).