High fasting insulin concentrations may be a pivotal predictor for the severity of hepatic fibrosis beyond the glycemic status in non-alcoholic fatty liver disease patients before development of diabetes mellitus.

BACKGROUND

Insulin resistance and type 2 diabetes mellitus (T2DM) contribute to the progression of non-alcoholic fatty liver disease (NAFLD). However, the relationship between glucose metabolic factors and the histological severity in NAFLD patients before development of T2DM is not well known.

METHODS

In 103 biopsy-proven NAFLD patients (68 men and 35 women) with hemoglobin A1c of <6.5% and fasting blood glucose of <126 mg/dL, we investigated whether glucose metabolic factors influenced the severity of hepatic fibrosis without prior known T2DM.

RESULTS

Female gender, age, serum aspartate aminotransferase, the aspartate aminotransferase/alanine aminotransferase ratio, fasting immunoreactive insulin (f-IRI), homeostasis model assessment - insulin resistance, hemoglobin A1c, hyaluronic acid, and type IV collagen 7 s were significantly higher, and 1,5-anhydroglucitol was significantly lower, in the fibrosis stage F3 group than in the F0-2 group. Multiple logistic regression analysis showed that only f-IRI (P = 0.006; odds ratio, 1.15151; 95% confidence interval, 1.04198-1.27254) was significantly indicated as a predictive factor for F3. As determined by both forward and backward stepwise selection analyses to optimize the model, f-IRI (P = 0001; odds ratio, 1.16788) remained an independent predictive factor for F3. To discriminate the F3 group from the F0-2 group, the area under the receiver operating characteristic curves showed that fasting insulin was 0.7219, and the best cut-off value of f-IRI was 13.2 μU/mL in the receiver operating characteristic curve analysis.

CONCLUSIONS

High fasting insulin concentrations may be a pivotal glucose metabolic predictor for the severity of hepatic fibrosis beyond the glycemic status in NAFLD patients before development of T2DM.