Hemoglobin A1c is a better predictor of prognosis following the non-ST elevation acute coronary syndrome than fasting and admission glucose

Abstract

Glucometabolic status is an important predictor of prognosis in patients with acute myocardial infarction. Both plasma glucose levels and glycosylated hemoglobin A1c (HbA1c) were implicated as predictors of prognosis. However, previous data yielded conflicting results. We evaluated the prognostic role of plasma glucose levels and HbA1c in patients with non-ST elevation acute coronary syndrome (NSTEACS). A total of 106 consecutive patients with NSTEACS (55 with unstable angina and 51 with non-ST elevation myocardial infarction) were included. The average age was 66.1 years; 61% were male. HbA1c was measured at admission, along with other standard laboratory values. The follow-up period lasted for a year. The main combined outcome variable included death from cardiovascular causes and rehospitalization due to another acute coronary syndrome or due to heart failure. Combined end point occurred in 43 (41%) patients. Mean HbA1c value was significantly higher in the group of patients who had complications (7.6 ± 2.6 vs. 5.8 ± 1.2, p < 0.05). Logistic regression identified HbA1c [odds ratio (OR): 1.6] and male sex (OR: 0.25) as the only independent predictors of major adverse cardiac events (MACE). A Kaplan-Meier analysis showed a 2.7 times higher risk of MACE in patients with HbA1c > 6.5%. Results from our study indicate that the admission level of HbA1c, but not admission or fasting glucose, is a predictor of mortality and major adverse events in patients with NSTEACS. These results identify HbA1c to be an independent predictor also in patients with NSTEACS, and not only in those with ST elevation myocardial infarction as observed before our study.