Correlation between insulin resistance and liver histology in patients with nonalcoholic steatohepatitis with and without obesity

Introduction Insulin resistance (IR) plays a central role in pathogenesis of nonalcoholic steatohepatitis (NASH). The aim of this study was to correlate histopathological grading and IR in overweight/obese patients with NASH as compared with lean NASH. Methods Patients with NASH who underwent liver biopsy between January 2012 and December 2012 were included. Anthropometric, clinical, and biochemical features, necro-inflammatory grades, and fibrosis stage on liver biopsies were scored according to Brunt and non-alcoholic fatty liver disease (NAFLD) activity score (NAS). Results Of 42 patients, 33 (78.6%) had body mass index (BMI) >= 23 kg/m(2) (overweight/obese) while 9 had BMI < 23 kg/m(2) (lean). Mean fasting blood sugar (FBS) and HbA1c levels in overweight/obese patients with NASH were higher than in lean NASH (p < 0.05). The median homeostatic model assessment-estimated insulin resistance (HOMA-IR) among NASH patients with BMI >= 23 kg/m(2) was higher than among those with BMI < 23 kg/m(2) (3.02 [0.34-17.22] vs. 2 [0.52-5.26]; p = 0.045). However, fasting insulin levels were comparable among lean and overweight/obese patients with NASH. Metabolic syndrome could be predicted with 75% sensitivity and 85.3% specificity at a HOMA-IR cutoff value of 3.9. No significant difference was observed with regard to HOMA-IR levels with Brunt grades, Brunt staging, Brunt grades 1 and 2, Brunt scores < 2 and > 2, and NAS scores, and NAS scores < 4 and > 4. Conclusions Although IR was significantly higher in overweight/obese patients with NASH as compared with that in lean patients with NASH, there was no difference in the correlation of HOMA-IR with histology between these groups.