Nonalcoholic fatty liver disease (NAFLD) is the hepatic manifestation of the metabolic syndrome (MetS) and defined as the accumulation of fat in the liver in patients who do not consume significant amounts of alcohol.1 NAFLD encompasses a wide spectrum of conditions, from simple fat accumulation (fatty liver) to steatohepatitis (NASH) with or without fibrosis up to the stage of cirrhosis.1 Features of MetS are highly prevalent in patients with NAFLD and the risk of developing NAFLD increases with the number of components of MetS. As a consequence, the increasing prevalence of MetS and NAFLD go hand in hand, and NAFLD is strongly associated with insulin resistance, type 2 diabetes, central adiposity, dyslipidemia, and hypertension.1,2
NAFLD affects an estimated 20-30% of people in the United States and is the leading cause of chronic liver disease in the Western World.2,3 NASH, the most aggressive form of the disease, when accumulation of liver fat is accompanied by cellular injury and inflammation, is estimated to affect 2-5% of Americans; however, the actual prevalence of NASH may be considerably higher due to the challenge of identifying patients with the disease, which remains largely symptomless until well advanced.3-5 The disease can progress to fibrosis, cirrhosis, and/or hepatocellular carcinoma (HCC)2,4 making these the second leading cause of liver transplants in the United States and poised to become the leading cause of transplants by 2020.6 Several clinician specialties are involved in the management of this disease, and the role of the endocrinologists, diabetologists, and primary care clinicians is crucial in the early recognition, diagnosis, and overall management of NAFLD and NASH.7
