title: Low serum total bilirubin concentrations are associated with increased prevalence of metabolic syndrome in Chinese.
abstract: BACKGROUND
  To investigate the association between serum concentrations of total bilirubin (TBil) in the physiological range and metabolic syndrome (MS) in middle-aged and elderly Chinese, as well as any associations between serum TBil concentrations and insulin resistance, hyperinsulinemia, and systemic inflammation.
  
  
  METHODS
  A cross-sectional study was conducted on 1423 individuals recruited from an urban community of Shanghai (average age 62.3 years) to investigate the relationship between bilirubin and cardiovascular diseases. Metabolic syndrome was defined according to the National Cholesterol Education Program Adult Treatment Panel III criteria for Asian Americans.
  
  
  RESULTS
  Total bilirubin concentrations were significantly lower in individuals with MS compared with those without (0.65 ± 0.21 vs 0.69 ± 0.22 mg/dL, respectively; P=0.002). The adjusted mean concentration of TBil decreased gradually with an increase in the number of components of MS (P(trend) < 0.0001). After adjustment for a range of potential confounders (e.g. age, sex, body mass index, smoking, alcohol intake, homeostasis model assessment of insulin resistance etc.), each 1 SD increase in TBil was found to be associated with a 17% reduction in the risk of MS (odds ratio 0.83; 95% confidence interval 0.73-0.95; P=0.006). Furthermore, after adjustment for all covariables, each 1 SD increase in TBil was found to be associated with lower odds of central obesity, hypertriglyceridemia, low high-density lipoprotein-cholesterol, and hyperglycemia. Serum TBil concentrations were inversely associated with hyperinsulinemia, insulin resistance, and systemic inflammation.
  
  
  CONCLUSIONS
  Serum TBil concentrations within the physiological range were inversely associated with MS and insulin resistance, hyperinsulinemia, and systemic inflammation in middle-aged and elderly Chinese.
authors.affiliation: Shanghai Clinical Center for Endocrine and Metabolic Diseases, Shanghai Institute of Endocrine and Metabolic Diseases, Department of Endocrine and Metabolic Diseases, Rui-Jin Hospital, 197 Rui-Jin 2nd Road, Shanghai, China.
authors.forename: Yaohua
authors.initials: Y
authors.lastname: Wu
authors.forename: Mian
authors.initials: M
authors.lastname: Li
authors.forename: Min
authors.initials: M
authors.lastname: Xu
authors.forename: Yufang
authors.initials: Y
authors.lastname: Bi
authors.forename: Xiaoying
authors.initials: X
authors.lastname: Li
authors.forename: Yuhong
authors.initials: Y
authors.lastname: Chen
authors.forename: Guang
authors.initials: G
authors.lastname: Ning
authors.forename: Weiqing
authors.initials: W
authors.lastname: Wang
mesh_terms: D000368:Aged; D044466:Asian People; D001663:Bilirubin / Q000097:blood*; D001786:Blood Glucose / Q000378:metabolism; D015992:Body Mass Index; D002318:Cardiovascular Diseases / Q000097:blood; D002681:China / Q000453:epidemiology; D002784:Cholesterol / Q000097:blood; D008076:Cholesterol, HDL / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D006946:Hyperinsulinism / Q000097:blood; D007249:Inflammation / Q000097:blood; D007333:Insulin Resistance; D016015:Logistic Models; D008297:Male; D024821:Metabolic Syndrome / Q000097:blood* / Q000208:ethnology; D008875:Middle Aged; D015999:Multivariate Analysis; D015995:Prevalence; D014280:Triglycerides / Q000097:blood; D014504:Urban Health / Q000706:statistics & numerical data*
chemical_list: D001786:Blood Glucose; D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D014280:Triglycerides; D002784:Cholesterol; D001663:Bilirubin