Is Nonalcoholic Fatty Liver Disease Indeed the Hepatic Manifestation of Metabolic Syndrome?

Metabolic syndrome (MetS) is a cluster of central obesity, dyslipidaemia, insulin resistance and hypertension. MetS frequently co-exists with non-alcoholic fatty liver disease (NAFLD), which is characterized by fat accumulation in the liver in the absence of alcohol abuse, viral hepatitis and other causes of chronic liver diseases. Both MetS and NAFLD are associated with an increased risk for cardiovascular disease and type 2 diabetes mellitus. There are also other associations between MetS and NAFLD. In the present narrative review, we discuss the links between MetS and NAFLD in terms of prevalence, risk factors and treatment (both lifestyle interventions and drug therapy). Such associations highlight the common pathophysiological pathways of these metabolic disorders, although data for an independent association are not robust. Nevertheless, NAFLD may be regarded as a hepatic manifestation of MetS.