Effects of prediabetes on coronary collateral circulation in patients with coronary artery disease Hasan Kadi, Koksal Ceyhan, Metin Karayakali, Atac Celik, Ahmet Ozturk, Fatih Koc and Orhan Onalan Background 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. Methods 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 v 2 , the Student t or the Mann–Whitney U-tests. To identify predictors of CCC, multivariable logistics regression analysis was performed. Results 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). Conclusion 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. Coron Artery Dis 22:233–237  c 2011 Wolters Kluwer Health | Lippincott Williams & Wilkins. Coronary Artery Disease 2011, 22:233–237 Keywords: collateral circulation, coronary artery disease, prediabetes Department of Cardiology, Faculty of Medicine, Gaziosmanpasa University, Tokat, Turkey Correspondence to Hasan Kadi, MD, Department of Cardiology, Faculty of Medicine, Gaziosmanpasa University, Tokat 60200, Turkey Tel: + 90 356 2129500; fax: + 90 356 2129526; e-mail: drhkadi@gmail.com Received 14 January 2011 Accepted 28 January 2011 Introduction According to the American Diabetes Association’s new de- scription, patients with impaired fasting plasma glucose are considered prediabetics [1]. It is estimated that 50% of patients with prediabetes will develop type II diabetes mellitus within 10 years [2]. Large-scale studies and meta-analyses indicated that mortality and future risks of cardiovascular conditions are increased in patients with prediabetes [3,4]. In an experimental study conducted by Weihrauch et al. [5], it was shown that chronic hyper- glycemia attenuates coronary collateral development. In addition, it has been reported that in patients with meta- bolic syndrome, coronary collateral development is im- paired [6,7]. In normal human heart, there are many collateral vessels linking major coronary arteries [8]. As most of the col- lateral channels in normal people or patients with mild coronary artery disease are small and carry only minimal flow, they do not appear in coronary angiography. In order for collateral vessels to appear, coronary artery should be 99 or 100% stenosis [9]. Coronary collateral circulation (CCC) is an alternative way of blood supply to ischemic region in coronary artery disease. Although some insights about collateral formation mechanisms were obtained as a result of the developments in molecular biology and genetic studies, the exact mechanism of collateral develop- ment is not known. Despite the fact that the only pre- requisite for collateral development is shown to be the degree of coronary artery stenosis [10], there are signi- ficant differences even among the patients with similar degree of coronary artery disease. Approximately one-third to one-quarter of the patients with coronary artery disease, especially the ones involving multiple arteries, are not suitable for revascularization procedures. In these patients, an alternative way of sup- plying blood to the distal part of the occluded artery is CCC. Therefore, a full understanding of factors affect- ing CCC development is important in treatment of the patients not suitable for revascularization procedures. The aim of this study is to study the effect of prediabetes on coronary collateral development in patients with coro- nary artery disease. Materials and methods Study design Retrospective, observational. Pathophysiology and natural history 233 0954-6928  c 2011 Wolters Kluwer Health | Lippincott Williams & Wilkins DOI: 10.1097/MCA.0b013e328345241b Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.