Association Between Glycated Hemoglobin and Severity of Coronary Artery Disease in Type 2 Diabetic Patients With Myocardial Infarction.

Background Cardiovascular disease is a leading cause of morbidity and mortality worldwide, with a high prevalence in developing countries, and coronary artery disease (CAD) is a major contributor to it. Diabetes mellitus is a major risk factor for CAD. However, research on the association between glycated hemoglobin (HbA1c) levels and severity of CAD is lacking in developing countries like Pakistan. Therefore, this study aimed to investigate the association between HbA1c levels and the severity of CAD in type 2 diabetic patients with myocardial infarction (MI). Method This cross-sectional study was conducted on 225 type 2 diabetic patients with CAD at Cardiology Unit, Jinnah Hospital, Lahore, Pakistan during the period of one year from August 2020 to August 2021. The recruitment of patients was done via consecutive sampling and predefined inclusion and exclusion criteria. Data was collected through a self-devised proforma. The Gensini scoring system was used to determine the CAD severity. Participants were stratified into two groups based on the Gensini score system. Statistical analysis was performed using IBM SPSS Statistics for Windows, Version 25 (Released 2017; IBM Corp., Armonk, New York, United States) via an independent t-test and chi-squared tests, Pearson's correlation coefficient, and linear regression analysis. A p-value < 0.05 was set statistically significant. Results Of 225 patients, 145 patients (64.45%) had non-severe CAD, while 80 patients (35.55%) had severe CAD. Patients with good glycemic control accounted for n=69 (30.66%), while those with poor glycemic control comprised n=156 (69.34%) of the study population. The differences in means with standard deviations (means ± SD) of Gensini scores (p=0.001) and HbA1c levels (p=0.002) between two study groups (patients with severe CAD and non-severe CAD) were statistically significant. A significant positive correlation was found between HbA1c levels and CAD severity (correlation coefficient (r)=0.75, p=0.002). Moreover, linear regression analysis endorsed the HbA1c level as an important predictor of CAD severity, with a beta coefficient (β) of 3.11 and a 95% CI of 1.52-4.60 (p < 0.001). Conclusion This study demonstrates a significant association between HbA1c levels and CAD severity in type 2 diabetic patients with MI. Elevated HbA1c levels are strongly linked to increased CAD severity, highlighting the importance of tight glycemic control in managing CAD in diabetic patients. This study suggests that HbA1c levels can serve as a preliminary marker for early detection of high-risk acute CAD patients, enabling prompt interventions and enhanced clinical outcomes.