Non-alcoholic fatty liver disease (NAFLD) currently represents the most common liver disease in Western countries, being
found in 25-30% of the general population. NAFLD embraces a wide range of metabolic hepatic damage characterised by steatosis and,
in some cases, associated non-alcoholic steatohepatitis (NASH). The long-term hepatic prognosis of NAFLD patients depends on the histological
stage at diagnosis: simple steatosis has a favourable outcome, whereas patients with NASH can develop cirrhosis and other
liver-related complications, including hepatocellular carcinoma.
Progression of fibrosis is thought to develop in up to one third of NASH patients, including the development of cirrhosis, but regression
is also possible in pre-cirrhotic stages. Independent predictors of fibrosis are older age, diabetes, obesity, hypertension, and the degree of
insulin resistance. Patients with NAFLD, particularly those with NASH, have a higher prevalence and incidence of clinically manifested
cardiovascular disease, independently of classical cardiometabolic risk factors. Hepatocellular carcinoma (HCC) is usually diagnosed at a
late stage, but it may also occur in non-cirrhotic NASH, as obesity and diabetes both independently increases the risk of developing HCC.
Liver-related mortality is increased up to ten-fold in patients with NASH.