title: Association of serum total bilirubin level with severity of coronary atherosclerosis is linked to systemic inflammation.
abstract: OBJECTIVE
  Although cardiovascular protective action of bilirubin has been attributed to its antioxidant effect, there was scarce data regarding the anti-inflammatory properties. Herein, we aimed to assess the relationship between serum total bilirubin level and severity of coronary artery disease (CAD) in association with the direct inflammatory marker such as C-reactive protein (CRP), the other indirect markers included in inflammation process such as neutrophil to lymphocyte ratio (NLR) and red cell distribution width (RDW) in patients with stable CAD.
  
  
  METHODS
  Angiographic data of 1501 patients were analyzed in this retrospective cross-sectional study. Patients were categorized according to Gensini scores as control, mild CAD and severe CAD groups. The association of clinical and laboratory parameters with the severity of CAD were determined by multivariable linear regression analysis.
  
  
  RESULTS
  Total bilirubin level in the control group was significantly higher than those of the other groups. After multivariable linear regression analysis total bilirubin [β=-3.131 (-4.481, -1.782), p<0.001] was significantly associated with the severity of CAD. Futhermore, there was a moderate and significant inverse correlation between serum total bilirubin level and the severity of CAD (r=-0.173, p<0.001), CRP (r=-0.112, p<0.001), NLR (r=-0.070, p=0.026) and RDW (r=-0.074, p=0.027).
  
  
  CONCLUSIONS
  Serum total bilirubin level was independently and inversely associated with the severity of coronary atherosclerosis in patients with stable CAD. In addition, total bilirubin level was inversely correlated with CRP, NLR and RDW. These results suggest that besides its already known effect on the oxidative stress, higher serum total bilirubin level may exhibit an anti-inflammatory effect in the coronary atherosclerotic process.
authors.affiliation: Turkiye Yuksek Ihtisas Education and Research Hospital, Department of Cardiology, Ankara, Turkey. Electronic address: mkakboga@yahoo.com.
authors.forename: Mehmet Kadri
authors.initials: MK
authors.lastname: Akboga
authors.affiliation: Turkiye Yuksek Ihtisas Education and Research Hospital, Department of Cardiology, Ankara, Turkey.
authors.forename: Ugur
authors.initials: U
authors.lastname: Canpolat
authors.affiliation: Gazi University Medical Faculty, Department of Cardiology, Ankara, Turkey.
authors.forename: Asife
authors.initials: A
authors.lastname: Sahinarslan
authors.affiliation: Gazi University Medical Faculty, Department of Cardiology, Ankara, Turkey.
authors.forename: Yakup
authors.initials: Y
authors.lastname: Alsancak
authors.affiliation: Gazi University Medical Faculty, Department of Cardiology, Ankara, Turkey.
authors.forename: Serdar
authors.initials: S
authors.lastname: Nurkoc
authors.affiliation: Turkiye Yuksek Ihtisas Education and Research Hospital, Department of Cardiology, Ankara, Turkey.
authors.forename: Dursun
authors.initials: D
authors.lastname: Aras
authors.affiliation: Turkiye Yuksek Ihtisas Education and Research Hospital, Department of Cardiology, Ankara, Turkey.
authors.forename: Sinan
authors.initials: S
authors.lastname: Aydogdu
authors.affiliation: Gazi University Medical Faculty, Department of Cardiology, Ankara, Turkey.
authors.forename: Adnan
authors.initials: A
authors.lastname: Abaci
mesh_terms: D000328:Adult; D000368:Aged; D001663:Bilirubin / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D002097:C-Reactive Protein / Q000032:analysis; D016009:Chi-Square Distribution; D017023:Coronary Angiography; D003324:Coronary Artery Disease / Q000097:blood* / Q000175:diagnosis / Q000276:immunology; D003430:Cross-Sectional Studies; D004909:Erythrocyte Indices; D005260:Female; D006801:Humans; D007249:Inflammation / Q000097:blood* / Q000175:diagnosis / Q000276:immunology; D018836:Inflammation Mediators / Q000097:blood*; D016014:Linear Models; D018655:Lymphocyte Count; D008214:Lymphocytes / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009504:Neutrophils / Q000276:immunology*; D011237:Predictive Value of Tests; D065840:Protective Factors; D012189:Retrospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index
chemical_list: D015415:Biomarkers; D018836:Inflammation Mediators; D002097:C-Reactive Protein; D001663:Bilirubin
keywords: Atherosclerosis; Bilirubin; CRP; Inflammation; NLR; RDW