Nonalcoholic fatty liver disease: Hepatic manifestation of obesity and the metabolic syndrome

Obesity is currently a worldwide epidemic, and will likely only increase in prevalence in the coming years. The incidence of the metabolic syndrome (MetS) seems to be paralleling obesity. The MetS is strongly linked to insulin resistance, abdominal obesity, diabetes mellitus, and dyslipidemia. Nonalcoholic fatty liver disease (NAFLD) is the hepatic manifestation of obesity and the MetS. Although not currently a formal component of the MetS, data suggest a very strong correlation between NAFLD and the MetS; insulin resistance appears to be the common factor. Nonalcoholic steatohepatitis (NASH) is a more advanced stage in the spectrum of NAFLD, which can progress to cirrhosis. Management strategies for NAFLD are conceivably similar to those for the MetS, which focus on lifestyle measures aimed at weight reduction and maintenance. The purpose of this review is to highlight the growing epidemic of obesity and the MetS, and the strong likelihood of an increase in the prevalence of the already widely existent combination of NAFLD/NASH. This article describes pharmacological treatments including novel therapies aimed at the hepatic pathophysiologic process, as well as surgical options. The increasing prevalence of obesity and the MetS places a large population at risk for developing hepatic failure. Therefore, NAFLD must be acknowledged as a major worldwide public health concern.