Association of Serum Concentrations of Bilirubin with Risk of Coronary Artery Disease / 대한임상병리학회지

ABSTRACT

BACKGROUND: Bilirubin has been suggested as a antioxidant which protect oxidation of lipids and lipoproteins. Given that oxidized lipids and lipoproteins are known to be atherogenic, low serum concentrations of bilirubin could be associated with the high risk of coronary artery disease (CAD). But few studies have been performed for confirmation of this hypothesis. In this study, we evaluated the relationship between serum concentrations of billrubln and the angiographically documented CAD. METHODS: Eighty five CAD patients and 56 non-CAD patients, classified according to the maximum stenosis of coronary artery at angiography, were enrolled in this study. The degree of the coronary arterial stenosis were subclassified into or =50% (severely stenotic CAD). We retro-spectively reviewed serum concentrations of total and direct bilrubin at the time of angiography, compared tine mean concentrations of bilirubin between two groups and evaluated it in relation to the severity of CAD by statistical analysis. RESULTS: The mean concentration of total bilrubin was significant1y lower in CAD group 4han non-CAD group (12.8 micromol/L vs. 15.2 micromol/L, p value=0.04) The mean concentration of direct bilirubin was lower in CAD group than non-CAD group but not statistically significant (3.3 micromol/L vs. 4.2 micromol/L, p value=0.07). Although not significant, the concentration of total bilirubin in severely stenotic group (12.8 CAD group 12.8+/-4.3 micromol/L) was lower than mildly stenotic group (13.5+/-3.8 micromol/L) and non CAD group (15.2+/-7.4 micromol/L ) (p=0.07). CONCLUSIONS: This study showed that low serum concentrations of total bilirubin were associated with the high risk of CAD and supports the hypothesis that serum bilirubin could act as an antiatherosclerotic factor. Further prospective studies are required to confirm the relationship between bilirubin and CAD and to elucidate the most associated fraction of bilirubin and pathogenic mechanism.