title: Serum bilirubin levels are lower in overweight asymptomatic middle-aged adults: an early indicator of metabolic syndrome?
abstract: OBJECTIVE
  Low levels of bilirubin have recently been associated with obesity, diabetes mellitus, and metabolic syndrome. Here, we hypothesized that serum bilirubin levels might be already altered in overweight asymptomatic middle-aged individuals before full development of the metabolic syndrome.
  
  
  METHODS
  Healthy nonsmoking adults aged 25-49 (64 women and 32 men) participated in this cross-sectional study. All participants who reported stable weight within the last three months underwent standard anthropomorphological measurements of body composition, blood pressure measurements, aerobic and anaerobic capabilities assessment, dietary intake evaluation, and fasting serological measurements of total and direct bilirubin, glucose, insulin, triglycerides, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and C-reactive protein. Participants were divided into normal-weight and overweight groups. Linear correlation and multiple regression analyses were used to examine the association of serum bilirubin levels with all metabolic syndrome risk factor changes.
  
  
  RESULTS
  Serum bilirubin levels were lower in overweight healthy individuals of both sexes, and were negatively associated with abdominal obesity, insulin resistance, fasting glucose, fasting insulin, fasting triglycerides, total cholesterol, low-density lipoprotein cholesterol, and C-reactive protein levels but positively associated with aerobic body capabilities.
  
  
  CONCLUSIONS
  Our findings suggest that serum bilirubin levels have the potential to be employed as an early biomarker for indicating asymptomatic individuals at increased risk of developing metabolic syndrome.
authors: Faculty of Health Sciences, University of Primorska, Polje 42, 6310 Izola, Slovenia.
authors: Zala
authors: Z
authors: Jenko-Pražnikar
authors: Ana
authors: A
authors: Petelin
authors: Mihaela
authors: M
authors: Jurdana
authors: Lovro
authors: L
authors: Žiberna
mesh_terms: D000328:Adult; D001663:Bilirubin / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D015992:Body Mass Index; D003430:Cross-Sectional Studies; D042241:Early Diagnosis; D005260:Female; D006801:Humans; D007333:Insulin Resistance; D016014:Linear Models; D008297:Male; D024821:Metabolic Syndrome / Q000150:complications* / Q000175:diagnosis / Q000453:epidemiology; D008875:Middle Aged; D050177:Overweight / Q000097:blood* / Q000150:complications; D012044:Regression Analysis; D012307:Risk Factors; D017524:Slovenia / Q000453:epidemiology
chemical_list: D015415:Biomarkers; D001663:Bilirubin