Association between glycosylated hemoglobin and acute coronary syndrome in type 2 diabetes mellitus

Abstract

Background and objective: Chronic hyperglycemia in type 2 diabetes increases the risk of microvascular events. However, the prognostic value of hemoglobin A1c (HbA1c) level in patients with coronary atherosclerotic disease has not been well characterized and remains controversial. This study was an attempt to know the association between HbA1c and acute coronary syndrome (ACS) in Indian type 2 diabetic patients. Materials and Methods: This study is a case-control study done at a tertiary care hospital. Cases were diabetic patients with ACS and controls were diabetic patients without any evidence of ACS. To eliminate confounding bias, matching was done between two groups for age, sex, duration of diabetes, presence of hypertension, smoking, and dyslipidemia. Patients belonging to either gender in age group of 40-80 years, with diagnosis of diabetes mellitus (as per American diabetic association (ADA) criteria) on treatment were selected. HbA1c was measured by immunological assay. Results: A total of 60 cases (Group A, diabetic patients with ACS) and 60 controls (Group B, diabetic patients without the evidence of ACS) were included in the study. Mean age of patients in group A is 64.22 ± 6.39 years and in group B is 64.48 ± 6.57 years. Duration of diabetes group in A is 9 ± 5.75 years and in group B is 9.2 ± 5.45 years. The association of HbA1c level with ACS was highly significant when analyzed by multiple regression analysis after adjusting for confounders (adjusted odds ratio (OR): 4.92, confidence interval (CI): 2.16-11.17, P = 0.0001).The difference in HbA1c level between the groups was highly significant in the whole groups (P < 0.0001) and when analyzed by categorizing the patients based on gender, presence of hypertension, dyslipidemia, and smoking. Conclusion: HbA1c level is strongly associated with risk of ACS. Occurrence of ACS was significantly more in patients with HbA1c level more than 7% when compared with patients with HbA1c level less than 7%.