RESUMO
Objective: To explore the relationship between serum bilirubin level and the severity of coronary artery disease (CAD). Methods: A total of 568 patients treated in our hospital from 2014-07 to 2016-03 were studied. Based on coronary angiography (CAG), the patients were divided into 2 groups: CAD group, n=438 and Non-CAD group, n=130. CAD group had 166 patients with single vessel disease, 150 with double vessel disease and 122 with triple vessel disease; taking Gensini score 34 as the border, there were 219 patients with low Gensini score and 219 with high Gensini score. Taking total bilirubin (TBIL) level>17.1 μmol/L as the border, the patients were divided into another set of 2 groups: Normal TBIL group, n=426 and High TBIL group, n=142. Clinical data, biochemical parameters, blood routine examination, color doppler ultrasound and CAG results were recorded. Blood levels of TBIL, direct bilirubin (DBIL) and indirect bilirubin (IBIL) were compared among different groups. Results: ①Compared with Non-CAD group, CAD group had decreased serum levels of TBIL, DBIL and IBIL, P<0.05, the detective rate of hyperbilirubinemia had decreasing trend; while detective rate of CAD was similar between Normal TBIL group and High TBIL group, P>0.05. ②In CAD group, the patients with more coronary branch lesions and the higher Gensini scores had the lower serum levels of TBIL, DBIL and IBIL, P<0.05. Pearson correlation analysis showed that TBIL, DBIL and IBIL were positively related to LVEF (r=0.390, r=0.283 and r=0.426), all P<0.05. ③Multi-linear regression analysis indicated that DBIL, IBIL level was the independent risk factor for CAD occurrence and having negative correlation to CAD (B=-3.766, B=-2.705), both P<0.05. ④TBIL, DBIL and IBIL levels were negatively related to hs-CRP in CAD patients (r=-0.617, r=-0.473 and r=-0.580),allP<0.05. Conclusion: Serum bilirubin level was negatively correlated to the degree of the cornary stenosis, which is independent of its forms, low bilirubin might be an independent risk factor of CAD occurrence.