The intersection between alcohol-related liver disease and nonalcoholic fatty liver disease

In this Review, Arrese and colleagues discuss the intersection of nonalcoholic fatty liver disease and alcohol-related liver disease, including their pathophysiology, clinical management and suggestions for future research. Nonalcoholic fatty liver disease (NAFLD) and alcohol-related liver disease (ALD) are the leading causes of chronic liver disease worldwide. NAFLD and ALD share pathophysiological, histological and genetic features and both alcohol and metabolic dysfunction coexist as aetiological factors in many patients with hepatic steatosis. A diagnosis of NAFLD requires the exclusion of significant alcohol consumption and other causes of liver disease. However, data suggest that significant alcohol consumption is often under-reported in patients classified as having NAFLD and that alcohol and metabolic factors interact to exacerbate the progression of liver disease. In this Review, we analyse existing data on the interaction between alcohol consumption and metabolic syndrome as well as the overlapping features and differences in the pathogenesis of ALD and NAFLD. We also discuss the clinical implications of the coexistence of alcohol consumption, of any degree, in patients with evidence of metabolic derangement as well as the use of alcohol biomarkers to detect alcohol intake. Finally, we summarize the evolving nomenclature of fatty liver disease and describe a recent proposal to classify patients at the intersection of NAFLD and ALD. We propose that, regardless of the presumed aetiology, patients with fatty liver disease should be evaluated for both metabolic syndrome and alcohol consumption to enable better prognostication and a personalized medicine approach.

Automated summary

In this Review, Arrese and colleagues discuss the pathophysiology, clinical management, and future research directions of nonalcoholic fatty liver disease (NAFLD) and alcohol-related liver disease (ALD), which are the leading causes of chronic liver disease worldwide. The authors highlight the shared features and interactions between alcohol and metabolic dysfunction in the development and progression of liver disease, as well as the under-reporting of alcohol consumption in patients classified as having NAFLD. They propose the evaluation of both metabolic syndrome and alcohol consumption in patients with fatty liver disease to improve prognosis and personalize treatment.