Clinical significance of glycated hemoglobin in acute coronary syndrome patients from the CCC-ACS project

Background Blood glucose levels are associated with the prognosis of patients with acute coronary syndrome (ACS). Glycated hemoglobin (HbA1c) reflects the average blood glucose level. The purpose of the study was to evaluate HbA1c as a prognostic indicator for ACS. Methods In total, 27,337 ACS patients from the CCC-ACS (Improving Care for Cardiovascular Disease in China - Acute Coronary Syndrome) project were enrolled in this study and divided into three groups according to HbA1c level: Group I, HbA1c level <5.7%; Group II, HbA1c level 5.7–6.4%; Group III, HbA1c level ≥6.5%. The primary outcome was an in-hospital major adverse cardiovascular event (MACE), such as all-cause death, recurrent myocardial infarction, acute or subacute stent thrombosis, heart failure, cardiogenic shock, or cardiac arrest. Baseline data and effectiveness outcome were compared among patients in the three groups. Results Group III had the highest MACE incidence (13.4% [Group III] vs. 8.7% [Group I] and 10.5% [Group II], p < 0.001). In the logistic regression, there was a statistically significant difference in HbA1c level between the groups (odds ratio [OR]: 1.110, 95% confidence interval [CI]: 1.008–1.133, p < 0.001). In the receiver operating characteristic curve, the area under the curve for MACE was 0.560 (95% CI: 0.550–0.571, p < 0.001); the cut-off value for the HbA1c level was 6.38%. Conclusion The HbA1c level was associated with the risk of MACEs in ACS patients with or without diabetes. Trial Registration clinicaltrials.gov, NCT02306616. Registered 3 December 2014—Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT02306616 .