Lean NAFLD: an Underrecognized Outlier
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Nonalcoholic fatty liver disease (NAFLD) is commonly diagnosed in obese or overweight individuals. However, lean individuals with NAFLD are not rare but represent one significant end of the phenotypic spectrum of NAFLD. Although initial observations between obese and lean NAFLD reveal some metabolic parallels, these associations vary widely given differences in study populations and metabolic parameters assessed. The role of body composition in risk assessment is significant and incompletely assessed during most clinical encounters. Recent multinational investigation reveals an increased mortality in lean individuals with nonalcoholic steatohepatitis (NASH). Many aspects of lean NAFLD need further exploration including epidemiology, clinical risk assessment, histologic changes unique to lean NAFLD, genetic and pathophysiologic mechanisms predisposing at risk individuals, natural history, and treatment strategies in this underrecognized population.
KeywordsLean Nonobese Normal weight Nonalcoholic fatty liver disease (NAFLD) Nonalcoholic steatohepatitis (NASH)
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JW and AJS declare that they have no conflicts of interest.
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This article does not contain any studies with human or animal subjects performed by any of the authors.
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