The importance of fatty liver disease in clinical practice

The worldwide obesity epidemic over the last 20 years has led to a dramatic increase in the prevalence of non-alcoholic fatty liver disease, the hepatic manifestation of the metabolic syndrome. Estimates of prevalence vary depending on the population studied and the methods used to assess hepatic fat content, but are commonly quoted as between 10 and 30% of the adults in the Western hemisphere. Fatty liver develops when fatty acid uptake and synthesis in the liver exceeds fatty acid oxidation and export as TAG. Studies of pathogenesis point to insulin resistance, lipotoxicity, oxidative stress and chronic inflammation being central to the development and progression of the disease. A proportion of individuals with fatty liver develop progressive disease, though large prospective longitudinal studies are lacking. Nevertheless, fatty liver is associated with increased all-cause and liver-related mortality compared with the general population. Management of fatty liver centres around lifestyle and dietary measures to induce controlled and sustained weight loss. Management of cardiovascular risk factors aims to reduce mortality, while certain dietary interventions have been shown to reduce steatosis and inflammation. Specific pharmacological treatments also show promise, but their use is not widespread. A multi-system and multi-disciplinary approach to the management of this disorder is proposed.