Natural History of Non Alcoholic Fatty Liver Disease and Predictors of Advanced Fibrosis

The prevalence of non-alcoholic fatty liver disease (NAFLD ) in the American population is approximately 30% in adults and 10% in children, making it the most common. Cause of chronic liver disease in the United States. Although the majority of patients with NAFLD have a benign clinical course, the development of non-alcoholic steatohepatitis (NASH ), with necro-inflammation and progressive fibrosis, increases the risk for development of cirrhosis and its complications. Among patients with NASH, approximately 28% develop cirrhosis over an 8-year follow-up period. NASH and advanced fibrosis is associated with increased morbidity and mortality among those patients with advanced histologic severity such as NASH and fibrosis the gold standard for diagnosing and staging NAFLD is liver biopsy. Liver biopsy is associated with costs and risks that make it impractical for generalized use in a condition that affects such a high portion of the population. Furthermore, liver biopsy is also limited by significant sampling error in NAFLD. Thus, there is a pressing need for accurate non-invasive predictors of NAFLD that would also allow differentiation of those subjects at higher risk of disease progression. At present, in the clinical setting, some demographic factors, blood tests, and imaging studies can be used to predict a higher risk of disease in patients being evaluated for NAFLD. These predictors, however, are of limited sensitivity and specificity compared with liver biopsy. The development and validation of accurate predictors and scoring systems to identify patients at higher risk for NASH and fibrosis would allow identification of subjects who would benefit the most from liver biopsy and potentially help monitor disease