Long-Term Outcomes of Nonalcoholic Fatty Liver Disease

Abstract

Nonalcoholic fatty liver disease (NAFLD) is a prevalent disease with 20–30 % of the population affected in many developed and developing countries. Studies assessing the prognosis of NAFLD have shown that simple steatosis has a benign long-term outcome without excess mortality compared to the general population but that patients with NASH or with fibrosis have increased long-term mortality with standardized mortality ratio of 1.34–2.6 and hazard ratio of 1.004–1.05. The excess mortality of NAFLD patients is mainly due to cardiovascular disease. Liver-related mortality is also elevated in patients with NAFLD, especially in those patients with NASH or advanced fibrosis. A simple noninvasive fibrosis marker such as the NAFLD fibrosis score might be useful for predicting overall mortality and cause-specific mortality in these patients. A proportion of NAFLD develop concomitant or subsequent NASH at a rate of 10–20 %, and about 10 % of NASH cases progress to cirrhosis. NAFLD can progress to HCC, especially in patients with cirrhosis or advanced liver fibrosis. In addition to these liver-related complications, metabolic complications can also occur. The incidence of newly developed diabetes is elevated in NAFLD patients, and nonfatal and fatal cardiovascular diseases occur more frequently in patients with NAFLD. Therefore, cardiovascular assessment and liver-related surveillance might be considered in patients with NAFLD. In summary, we should pay more attention to patients with NAFLD, especially those with advanced forms of the disease because these individuals have increased morbidity and mortality.