Risk factors for severe coronary artery disease - a case-control study of patients who have undergone coronary artery bypass grafting.

To investigate risk factors for coronary artery disease (CAD), we analyzed the clinical parameters of patients with a coronary artery bypass graft (CABG) in a case-control study. Eighty-eight patients (75 males and 13 females) who underwent CABG surgery between 2001 and 2002 were compared with age- and sex-matched healthy controls randomly chosen from the registry of Kobari Health Care Center. Wilcoxon’s signed rank test and McNemar’s test were used for pairwise comparisons. Multivariate logistic regression analysis was used to identify significant risk factors for CABG. Significant differences between the patients and controls were observed in HDL-C (p < 0.001), HbA1c (p < 0.001), Brinkman Index (BI; p < 0.001), body mass index (BMI; p = 0.002), and systolic blood pressure (SBP; p = 0.013). Subjects with an abnormal BMI, HbA1c, or HDL-C or high BI value made up a significantly higher proportion of the patients who underwent CABG, compared to their age- and sex-matched controls. Multivariate logistic regression analysis identified high levels of HbA1c, low levels of HDL-C, and high scores on the BI as significant risk factors for needing a CABG. These results demonstrate that, despite the modification of laboratory determinations by antecedent treatment, HDL-C, HbA1c, BI, BMI, and SBP are significant indicators of risk for CAD.