Nonalcoholic Fatty Liver Disease: A Wide Spectrum Disease

Nonalcoholic Liver Disease (NAFLD) is considered a wide spectrum progressive disease and has emerged as a major cause of chronic liver disease worldwide. It has a global prevalence of 24%, an increasing incidence in both adults and children, in parallel with the pandemic burden of obesity, Type 2 Diabetes Mellitus (T2DM) and Metabolic Syndrome (MS). The pathogenic drivers are still unknown and are not likely to be identical among all patients. The natural history of NAFLD is not linear: it progresses to Nonalcoholic Steatohepatitis (NASH) in 10–30% of the cases, and about 10–15% of NASH patients progress to cirrhosis. The major cause of mortality of NAFLD patients is cardiovascular disease (CVD), being liver-related mortality only the third cause. New valid markers to distinguish patients who progress to either cirrhosis or CVD and new treatments are still to be developed. In spite of the great efforts devoted to achieving these goals, real options for new non-invasive markers for the diagnosis of NASH-cirrhosis and new therapeutic agents are still limited. This chapter will discuss the most updated data about the epidemiology, risk factors, pathogenesis, available experimental models, new diagnostic tools and new treatment options for NAFLD and NASH.