In nondiabetic patients, elevated admission glucose level is a strong predictor of short-term adverse outcome in patients with acute coronary syndrome. Admission glucose may be affected by meals, the circadian cycle, and also the stress response. Glycated hemoglobin A1c is a convenient marker of long-term glucose regulation. However, the prognostic value of diabetic control assessed by HbA1c level in patients with acute coronary syndrome (ACS) is still undefined.
To determine the association between (admission glucose and HbA1c) and short term outcome in patients not known to be diabetics presented with ACS.
PATIENTS AND METHODS:
This observational study included 50 consecutive patients without known diabetes mellitus admitted to the coronary care unit with ACS. Patients were sub-divided into three groups: patients with unstable angina (UA, n = 10), those with ST segment elevation myocardial Infarction (STEMI, n = 18) and those with non ST segment elevation myocardial infarction (NSTEMI, n = 22). Patients were stratified according to their HbA1c into three groups: Group 1: <6.5
(12, 24%), group 2: 6.5- 8.5 (22, 44%) and group 3: > 8.5 (16, 32%). Both glucose and HbA1c were measured on admission. The diagnosis of ‘‘undiagnosed DM’’ was made if patients presented with fasting glucose >7.0 mmol/L or random glucose >11.1 mmol/L together with an admission HbA1c >6.5% according to the latest ADA recommendations. Main outcome measure was left ventricular (LV) systolic function which was assessed by ejection fraction (EF); and the set point was 50%. Data were analyzed separately using multiple regression analysis.
The mean age of patients was 60.6 ± 6.33 years and 74% were males. Of total, 42% were smokers, 68% were hypertensive, 48% had hyperlipidemia and BMI ≥ 30 in 22%. Eighteen percent of patients were diagnosed as new cases of DM. Mean admission glucose was higher in patients with EF< 50% compared to those with EF> 50% with statistically significant difference (P< 0.05). There was a linear correlation between EF% and HbA1c in all types of presentation. 95.5% of patients in group 2 and 100% of patients in group 3 showed EF<50% with statistically significant difference (P< 0.05).
HbA1c on admission is a powerful predictor of LV systolic dysfunction as a major adverse event of acute coronary syndrome in patients not known to be diabetics. Measurement of HbA1c levels may improve risk assessment in those patients when presenting with ACS