Glycated Hemoglobin (HbA1c) Correlation with Severity of Coronary Artery Disease in Non-diabetic Patients - A Hospital based Study from North-Eastern India

Introduction: Glycated Hemoglobin (HbA1c) levels are predictive of cardiovascular disease and mortality in patients with diabetes mellitus, however, association of HbA1c with Coronary Artery Disease (CAD) in non-diabetics is inconsistent. Aim: To evaluate the correlation between HbA1c level and severity of CAD in non-diabetic patients using syntatax score in a cohort of proven CAD on angiography at Gauhati Medical College, Guwahati, Assam, India, which is a major tertiary care hospital of North-Eastern India. Materials and Methods: We prospectively collected data of non-diabetic patients with proven CAD on angiography from June 2014 to June 2015. Patients were divided into four groups (interquartiles) according to HbA1c levels, less than 4.8%, 4.8% to 5.1%, 5.1% to 5.6%, and 5.6% to 6.5%. Severity of CAD was assessed using syntatax score and the number of coronary vessels diseased. We compared different quartiles of HbA1c with regard to syntatax score and number of diseased vessels. Results: A total of 346 patients were included in the study. Mean age was 58.1 +/- 10.4 years. Of the total 91.9% (318) were males, 44.8% (155) were hypertensives, 29.2% (101) were smokers and 34.7% (120) were dyslipidemic. We found that CAD severity by syntatax score as well as number of vessels involved was significantly different among quartiles (p-values <0.001 and <0.001 respectively). Increase in HbA1c level was strongly correlated with disease severity and higher syntatax score. A significant increase was noted in the mean number of diseased vessels (p-value <0.001) as HbA1c level increases. Age, gender, hypertension and dyslipidemia did not show significant difference among quartiles however smoking was found to be an independent predictor of severity of CAD by syntatax score (p <0.05). Conclusion: From this clinical study, we can conclude that a significant correlation exists between HbA1c and severity of CAD by syntatax score as well as number of vessels involved in non-diabetes.