Prognostic factors for regression from impaired glucose tolerance to normal glucose regulation in Japanese patients with nonalcoholic fatty liver disease.

Objective: The aim of this retrospective cohort study was to assess the predictive factors for the regression from impaired glucose tolerance (IGT) to normal glucose regulation (NGR) in patients with nonalcoholic fatty liver disease (NAFLD).

Methods: A total of 164 NAFLD patients who had IGT in the first 75-g oral glucose tolerance test (OGTT) and underwent a repeated OGTT five years later were enrolled. A multivariate logistic regression analysis was carried out to identify factors predicting the regression from IGT to NGR.

Results: Out of the 164 patients, 29 regressed from IGT to NGR within five years after the first OGTT. The multivariate analysis by logistic regression showed that regression from IGT to NGR occurred when the patient was young (risk ratio for ten years: 0.38; 95% confidence interval [CI] 0.20-0.72; p=0.003), had a fasting plasma glucose (FPG) level of <100 mg/dL (risk ratio: 6.53; 95%CI 1.88-21.73; p=0.003), had a 2-hr post-load plasma glucose (PG) level of <160 mg/dL (risk ratio: 4.86; 95%CI 1.08-22.72; p=0.040), a body mass index (BMI) decrease of ≥1.5 (risk ratio: 5.20; 95% CI 1.41-19.24; p=0.014), physical activity of ≥2 Metabolic Equivalent of Task (MET) h/day (risk ratio: 5.57; 95%CI 1.68-18.44; p=0.005), and showed disappearance of the fatty liver by ultrasonography at five years (risk ratio: 9.92; 95%CI 2.87-34.34; p<0.001).

Conclusion: Our results suggest that six factors: young age, FPG <100 mg/dL, 2-hr post-load PG of <160 mg/dL, BMI decrease of ≥1.5, physical activity of ≥2 MET h/day, and the disappearance of fatty liver predict the regression from IGT to NGR in NAFLD patients.