Serum total bilirubin levels and disease severity in patients with stable coronary artery disease.

Aim: Serum total bilirubin (STB), a protective cardiovascular factor, was retrospectively investigated to determine the relationship between STB levels and the severity of disease in Chinese patients with stable coronary artery disease (CAD).
Patients and Methods: A total of 347 eligible patients presenting to our department from December 2007 to December 2012 were divided into tertiles according to their Syntax scores (low, moderate, and high). To clarify the association between STB levels and major adverse cardiovascular events (MACE), all patients were divided into two groups according to the median baseline STB (greater than or less than 13.2 μmol/l), which was measured after at least 12-h fast. All participants were followed for a mean of 37.1 months for MACE, including all-cause death, recurrent nonfatal myocardial infarction, and recurrent percutaneous coronary intervention.
Results: The STB levels were significantly lower in the high Syntax score group than those of the other groups and were negatively correlated with the Syntax score and number of diseased vessels. Follow-up data showed a higher incidence of MACE in the low STB group compared with the high STB group. Elevated STB levels predict the long-term prognosis of patients with stable angina pectoris. Finally, Kaplan-Meier analysis showed a significantly higher event-free survival rate in the patients with high STB levels than those in the low STB group.
Conclusions: STB levels were independently associated with the severity of disease in patients with stable CAD. Elevated STB is associated with cardiovascular events and may be useful as a biomarker of the severity and prognosis of stable CAD.