title: Histological severity and clinical outcomes of nonalcoholic fatty liver disease in nonobese patients.
abstract: Although nonalcoholic fatty liver disease (NAFLD) is closely linked to obesity, around 10%-20% of nonobese Americans and Asians still develop NAFLD. Data on this special group are limited. We therefore studied the severity and clinical outcomes of nonobese NAFLD patients. Consecutive NAFLD patients who underwent liver biopsy were prospectively recruited. We used the NASH Clinical Research Network system to score the histology. The Asian body mass index cutoff of 25 kg/m2was used to define nonobese NAFLD. Among 307 recruited NAFLD patients, 72 (23.5%) were nonobese. Compared to obese patients, nonobese patients had lower NAFLD activity score (3.3 ± 1.3 vs. 3.8 ± 1.2; P = 0.019), mainly contributed by steatosis (1.7 ± 0.8 vs. 2.0 ± 0.8; P = 0.014) and presence of hepatocyte ballooning (60.9% vs. 73.4%; P = 0.045). Similarly, nonobese patients had lower fibrosis stage (1.3 ± 1.5 vs. 1.7 ± 1.4; P = 0.004), serum cytokeratin-18 fragments (283 vs. 404 U/L; P < 0.001) and liver stiffness measurement by transient elastography (6.3 vs. 8.6 kilopascals; P < 0.001). By multivariate analysis in nonobese patients, only elevated serum triglyceride level was independently associated with higher NAFLD activity score (adjusted odds ratio [OR], 1.644; P = 0.021), whereas elevated creatinine level was the only factor associated with advanced fibrosis (adjusted OR, 1.044; P = 0.025). After a median follow-up of 49 months, 6 patients died, 2 developed hepatocellular carcinoma, and 1 had liver failure, all of whom were in the obese group.
  
  
  
  Nonobese NAFLD patients tend to have less-severe disease and may have a better prognosis than obese patients. Hypertriglyceridemia and higher creatinine are the key factors associated with advanced liver disease in nonobese patients. (Hepatology 2017;65:54-64).
authors.affiliation: Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Shatin, Hong Kong.
authors.forename: Jonathan Chung-Fai
authors.initials: JC
authors.lastname: Leung
authors.affiliation: Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Shatin, Hong Kong.
authors.forename: Thomson Chi-Wang
authors.initials: TC
authors.lastname: Loong
authors.affiliation: Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Shatin, Hong Kong.
authors.forename: Jeremy Lok
authors.initials: JL
authors.lastname: Wei
authors.affiliation: Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Shatin, Hong Kong.|State Key Laboratory of Digestive Disease, The Chinese University of Hong Kong, Shatin, Hong Kong.
authors.forename: Grace Lai-Hung
authors.initials: GL
authors.lastname: Wong
authors.affiliation: Department of Anatomical and Cellular Pathology, The Chinese University of Hong Kong, Shatin, Hong Kong.
authors.forename: Anthony Wing-Hung
authors.initials: AW
authors.lastname: Chan
authors.affiliation: Department of Anatomical and Cellular Pathology, The Chinese University of Hong Kong, Shatin, Hong Kong.
authors.forename: Paul Cheung-Lung
authors.initials: PC
authors.lastname: Choi
authors.affiliation: Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Shatin, Hong Kong.|State Key Laboratory of Digestive Disease, The Chinese University of Hong Kong, Shatin, Hong Kong.
authors.forename: Sally She-Ting
authors.initials: SS
authors.lastname: Shu
authors.affiliation: Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Shatin, Hong Kong.|State Key Laboratory of Digestive Disease, The Chinese University of Hong Kong, Shatin, Hong Kong.
authors.forename: Angel Mei-Ling
authors.initials: AM
authors.lastname: Chim
authors.affiliation: Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Shatin, Hong Kong.|State Key Laboratory of Digestive Disease, The Chinese University of Hong Kong, Shatin, Hong Kong.
authors.forename: Henry Lik-Yuen
authors.initials: HL
authors.lastname: Chan
authors.affiliation: Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Shatin, Hong Kong.|State Key Laboratory of Digestive Disease, The Chinese University of Hong Kong, Shatin, Hong Kong.
authors.forename: Vincent Wai-Sun
authors.initials: VW
authors.lastname: Wong
mesh_terms: D001706:Biopsy; D005260:Female; D006801:Humans; D008099:Liver / Q000473:pathology; D008297:Male; D008875:Middle Aged; D065626:Non-alcoholic Fatty Liver Disease / Q000150:complications / Q000473:pathology*; D009765:Obesity / Q000150:complications; D011379:Prognosis; D011446:Prospective Studies; D012720:Severity of Illness Index