The Threshold of Admission Glycemia as a Predictor of Adverse Events in Diabetic and Non-Diabetic Patients with Acute Coronary Syndrome

Recent studies indicated a high prevalence of hyperglycemia in non-diabetic patients presenting with acute coronary syndrome (ACS). However, the threshold of admission glucose (AG) as a predictor of adverse events in ACS is unclear. OBJECTIVE: The aim of this study was to assess the threshold of admission glucose (AG) as a predictor of adverse events including Major Acute Cardiac Events (MACE) and mortality, during the first week of admitting patients presenting with ACS. MATERIAL AND METHODS: The data of 551 patients with ACS were extracted and evaluated. Patients were stratified according to their blood glucose on admission into three groups: group 1: ≤7 mmol/L (n = 200, 36.3%) and group 2: >7 mmol/L and <15 mmol/L (n = 178, 32.3%) and group 3: ≥15 mmol/L (n = 173, 31.4%). Stress hyperglycemia was arbitrarily defined as AG levels > 7 mmol/L (group 2 and 3). Patients with ACS were sub-divided into two groups: patients with unstable angina (UA, n = 285) and those with ST segment elevation myocardial Infarction (STEMI, n = 266) and data were analyzed separately using multiple regression analysis. RESULTS: The mean age of patients was 59.7 ± 14.8 years and 63% were males. The overall mortality in the population was 8.5% (5.4% in STEMI and 3.1% in UA) patients. In STEMI patients, the odds ratio of stress hyperglycemia as predictor of mortality in group 3 compared with group 1 was 3.3 (CI 0.99–10.98, P < 0.05), while in group 2 compared with group 1 was 2.4 (CI: 0.75–8.07, P = 0.065) after adjustment for age and sex. Similarly, in UA patients, the odds ratio of stress hyperglycemia in group 3 compared with group 1 was 2.7 (CI 0.37–18.98, P < 0.05), while in group 2 compared with group 1 was 2.4 (CI: 0.4–15.2, P = 0.344) after adjustment for age and sex. The incidence of more than 2 MACE in both STEMI and UA patients was higher in group 3 compared with the other two groups. Regression analysis showed that history of DM, high level of LDL cholesterol, high level of HbA1c, and anterior infarction were significant predictors of adverse events while other risk factors such as BMI, history of hypertension and smoking were of no significance. CONCLUSION: This study indicates that the stress hyperglycemia on admission is a powerful predictor of increased major adverse events and hospital mortality in patients with acute coronary syndrome.