Nonalcoholic Fatty Liver Disease and its association with Insulin Resistance: A Study from Bangladeshi Newly Diagnosed Impaired Glucose Tolerance Subjects

Abstract

Background: Nonalcoholic fatty liver disease (NAFLD) is a clinicopathological condition strongly associated with obesity, type 2 diabetes, and metabolic syndrome. NAFLD is more prevalent in T2DM subjects but in the prediabetic state, particularly in impaired glucose tolerance (IGT) very, limited data are elucidated. The present study is aimed to examine the association of insulin resistance with NAFLD in subjects with newly diagnosed IGT. Methods: We studied 74 purposively recruited IGT [M/F, 34/40; age (ranges) in years, (25-64)] subjects whose NAFLD was confirmed by ultrasound assessment of the liver. IGT was diagnosed by 75 g OGTT as per WHO Group Study criteria. Serum glucose was measured by glucose-oxidase method. Serum insulin was measured by ELISA technique. Insulin resistance (HOMA-IR) was calculated by homeostasis model assessment (HOMA). Results: Compared to the without NAFLD counterparts, NAFLD subjects showed significantly higher levels of fasting serum insulin (17.26 ± 8.49 vs. 13.38 ± 4.40, p=0.015), postprandial serum insulin (90.06 ± 42.23 vs. 69.87 ± 38.10, p=0.034) and HOMA-IR (2.20 ± 1.0 vs. 1.73 ± 0.55, p=0.012) as well as significantly lower levels of HOMA%S (52.13 ± 20 vs. 63.92 ± 25.44, p=0.029). On multiple linear regression analysis, the fatty liver group showed significant positive association with HOMA-IR (β=0.270, p=0.020) after adjusting the effects of major confounders of sex, percent body fat (%BF) and body mass index (BMI). On binary logistic regression analysis, HOMA-IR was found to be a significant determinant of NAFLD (OR=2.679, 95% CI: 1.079-6.652, p=0.034) after adjusting the effects of %BF, BMI, and triglyceride (TG). Conclusions: High proportions (about forty seven percent) of IGT subjects are more likely to develop NAFLD. Altered glucose metabolism and fatty liver are associated with each other where insulin resistance plays linking role between their associations.