Factors Associated with Advanced Fibrosis in Patients with Nonalcoholic Fatty Liver Disease

Introduction. Nonalcoholic fatty liver disease includes conditions such as nonalcoholic steatosis and nonalcoholic steatohepatitis, with varying degrees of fibrosis that can progress to cirrhosis and hepatocellular carcinoma. Although the gold standard for its diagnosis remains liver biopsy, many non-invasive methods have been proposed to aid in both the diagnosis of the disease and the evaluation of the presence of liver fibrosis, which is a strong and independent factor for liver related mortality. Objectives. The objectives of this study were: 1) to identify the clinical and laboratory features associated with the presence of advanced fibrosis in individuals with biopsy-confirmed nonalcoholic fatty liver disease; 2) to evaluate the performance of non-invasive markers in identifying patients with advanced fibrosis. Methods. A cross-sectional-analytic study that evaluated patients with nonalcoholic fatty liver disease treated in the outpatient clinic of a university hospital of reference in hepatology, between January 2013 and December 2016. Results. 81 patients aged 53.3 ± 9.8 years were included in this study; 39.5% were men and 70.1% were obese. When comparing patients with advanced fibrosis to those without advanced fibrosis, patients with advanced fibrosis had a lower proportion of males than females (17.6 vs. 45.4%, p = 0.038), a higher proportion of hypothyroidism (29.4 vs. 6.3%, p = 0.017) and a higher median AST (52 vs. 31 U/L, p = 0.005). In logistic regression analysis, only hypothyroidism was independently associated with advanced fibrosis (OR = 4.975; CI 95% 1.050 - 23.574; p = 0.043). Spearman correlation analysis showed that higher levels of fibrosis on liver biopsy, were associated with higher levels of TSH (r = 0.304; p = 0.036), AST (r = 0.277; p = 0.019), GGT (r = 0.284; p = 0.017) and LDL (r = 0.258; p = 0.037). Regarding the performance of the non-invasive markers, the area under the ROC curve of Fibrosis 4 score was 0.723 (p = 0.008), that of Nonalcoholic fatty liver disease fibrosis score was 0.713 (p = 0.022), that of gamma-glutamyl transferase platelet ratio was 0.697 (p = 0.019) and that of aspartate-to-alanine aminotransferase ratio was 0.689 (p = 0.031). Conclusions. Hypothyroidism is a factor independently associated with advanced fibrosis. In the outpatient setting, non-invasive markers may be useful in identifying patients with advanced fibrosis.