title: Serum bilirubin levels are inversely associated with nonalcoholic fatty liver disease.
abstract: OBJECTIVE
  Serum bilirubin exerts antioxidant and cytoprotective effects. In addition, elevated serum bilirubin levels are associated with a decreased risk of metabolic and cardiovascular diseases. However, few studies have evaluated whether serum bilirubin is associated with non-alcoholic fatty liver disease (NAFLD), which is closely associated with other metabolic diseases. The aim of this study was thus to elucidate the association between serum total bilirubin levels and NAFLD.
  
  
  METHODS
  A cross-sectional study of 17,348 subjects undergoing a routine health check-up was conducted. Subjects positive for hepatitis B or hepatitis C virus, or with other hepatitis history were excluded. NAFLD was diagnosed on the basis of typical ultrasonographic findings and an alcohol consumption of less than 20 g/day.
  
  
  RESULTS
  The mean age of the subjects was 49 years and 9,076 (52.3%) were men. The prevalence of NAFLD decreased steadily as the serum bilirubin level increased in both men and women (P<0.001 for both). Multivariate regression analysis adjusted for other metabolic risk factors showed that serum bilirubin level was inversely associated with the prevalence of NAFLD [odds ratio (OR)=0.88, 95% confidence interval (CI)=0.80-0.97]. Furthermore, there was an inverse, dose-dependent association between NAFLD and serum total bilirubin levels (OR=0.83, 95% CI=0.75-0.93 in the third quartile; OR=0.80, 95% CI=0.71-0.90 in the fourth quartile vs. lowest quartile, P for trend <0.001).
  
  
  CONCLUSIONS
  Serum bilirubin levels were found to be inversely associated with the prevalence of NAFLD independent of known metabolic risk factors. Serum bilirubin might be a protective marker for NAFLD.
authors: Department of Internal Medicine, Healthcare Research Institute, Seoul National University Hospital Healthcare System Gangnam Center, Seoul, Korea.
authors: Min-Sun
authors: MS
authors: Kwak
authors: Donghee
authors: D
authors: Kim
authors: Goh Eun
authors: GE
authors: Chung
authors: Seung Joo
authors: SJ
authors: Kang
authors: Min Jung
authors: MJ
authors: Park
authors: Yoon Jun
authors: YJ
authors: Kim
authors: Jung-Hwan
authors: JH
authors: Yoon
authors: Hyo-Suk
authors: HS
authors: Lee
mesh_terms: D000328:Adult; D000428:Alcohol Drinking; D001663:Bilirubin / Q000097:blood*; D003430:Cross-Sectional Studies; D004279:DNA, Viral / Q000097:blood; D005234:Fatty Liver / Q000150:complications / Q000000981:diagnostic imaging* / Q000453:epidemiology; D005260:Female; D006509:Hepatitis B / Q000150:complications; D006526:Hepatitis C / Q000150:complications; D006801:Humans; D008297:Male; D008875:Middle Aged; D065626:Non-alcoholic Fatty Liver Disease; D016017:Odds Ratio; D015995:Prevalence; D012367:RNA, Viral / Q000097:blood; D012044:Regression Analysis; D012307:Risk Factors; D014463:Ultrasonography; D055815:Young Adult
chemical_list: D004279:DNA, Viral; D012367:RNA, Viral; D001663:Bilirubin
keywords: Bilirubin; Nonalcoholic fatty liver disease (NAFLD)