The development of a non-invasive model to predict the presence of non-alcoholic steatohepatitis in patients with non-alcoholic fatty liver disease

Non-alcoholic steatohepatitis (NASH) is an advanced and aggressive form of non-alcoholic fatty liver disease (NAFLD), which remains difficult to diagnose without a liver biopsy. Hyperferritinemia has increasingly been associated with the presence of NASH. Hence, we sought to explore the relationship between ferritin and NASH and to develop a composite model based on ferritin to predict the presence of NASH.A total of 405 patients with biopsy-proven NAFLD were enrolled in the study. Comparison was explored to assess differences between patients with and without NASH, upon which a scoring model was established using variables found to be independent predictors of NASH.Among all patients with NAFLD, 291 (72%) had biopsy-proven NASH, and 114 (28%) had non-NASH. Mean age was 48 ± 12 years, and 56% were female. Ferritin was significantly higher in NASH compared with non-NASH patients (184 vs 126, respectively; P 0.001) but lacked diagnostic accuracy for predicting NASH alone (area under the curve [AUC 0.62]). The addition of other significant variables such as aspartate aminotransferase, body mass index, platelet count, diabetes, and hypertension to ferritin improved the prediction of NASH with an AUC 0.81 (95% confidence interval: 0.76-0.86). Internal validation of the model using imputed data sets demonstrated that AUC did not change materially.While higher ferritin was significantly associated with NASH, ferritin alone lacked diagnostic accuracy to predict NASH. However, incorporating several easily obtainable variables with ferritin allowed the construction of a novel scoring system that can be easily applied in the clinical setting to guide management of NAFLD.