Effects of prediabetes on coronary collateral circulation in patients with coronary artery disease

The risk for cardiovascular disease almost increases in patients with impaired glucose tolerance compared with those with normal glucose tolerance. In experimental studies, it has been shown that impaired fasting glucose has negative effect of coronary collateral circulation (CCC). The aim of this study is to investigate the effects of prediabetes on coronary collateral development in patients with coronary artery disease.

We retrospectively enrolled 230 patients who underwent coronary angiography. All study participants had at least one occluded major coronary artery. Prediabetes was defined according to the American Diabetes Association definition and patients were then classified into having prediabetes group and control group. To classify CCC we used Rentrop's scoring system. Rentrop grades of 0 and 1 indicate poor CCC whereas 2 and 3 indicate good CCC. Groups were compared using the χ, the Student t or the Mann-Whitney U-tests. To identify predictors of CCC, multivariable logistics regression analysis was performed.

The prediabetes group consisted of 104 patients and the control group consisted of 126 patients. Both groups were comparable for basal characteristics. Poor CCC was higher in the patients with prediabetes (P < 0.001). Multivariable logistic regression analysis showed that fasting glucose level was the only independent predictor of CCC (B = -0.124; odds ratio = 0.883; 95% confidence interval = 0.85-0.92; P < 0.001).

Our study showed that coronary collateral development was impaired in patients with prediabetes when compared with patients with coronary artery disease who had normal fasting glucose level.