The role of hemoglobin A1c as a predictor of major adverse cardiovascular events in patients with type 2 diabetes mellitus after percutaneous coronary intervention: a case-cohort study

Abstract Background Few studies have investigated the potential predictive value of glycosylated hemoglobin A (HbA1c) and clinical outcomes in diabetic patients after percutaneous coronary intervention (PCI), and the results of the reports have often been inconclusive and contradictory. We have organized a study to investigate the relationship between HbA1c and the occurrence of major adverse cardiovascular events (MACE) in diabetic patients after PCI. Methods This case-cohort study was conducted on 563 diabetic patients who underwent PCI. All studied patients had an HbA1c level measured within 24 h before angioplasty. All patients were followed for six months regarding the occurrence of MACE, and the HbA1c level was measured again at the end of the sixth month of follow-up. In the case of MACE, the subjects were considered the case group, and other non-MACE patients were included in the control group. Results 505 patients remained in the study at the end of follow-up. MACE occurred in 23 (4.6%) patients during the first month and in 57 (11.3%) patients by the end of the sixth month. Baseline HbA1c was an independent predictor of MACE and mortality at the end of month-6 (P = 0.008 and 0.001, respectively). Conclusions The level of HbA1c at the time of admission has a significant predictive value for the occurrence of MACE in diabetic patients who undergo PCI. However, post-PCI glycemic control may not effectively reduce the risk of MACE in this population. Clinical trial registration Not applicable.