Impact of prediabetes on cardiovascular disease risk in patients with acute myocardial infarctions

Aim: Prediabetes is known to be associated with increased cardiovascular diseases (CVD) risk and mortality. It has been reported that more than 70% of pre-diabetic patients develop Diabetes Mellitus (DM). In patients with acute myocardial infarction (AMI), diabetes increases a 2 to 4 fold risk of adverse cardiovascular events compared to non-diabetic patients. This morbidity-mortality relationship begins in the progression phase from normal glucose tolerance to diabetes. We evaluated the relationship between the presence of pre-diabetes by using hemoglobin A1c (HbA1c) values and CVD risk in patients presenting with newly diagnosed AMI. Methods: This study was a retrospective, single-centre and we examined consecutive patients who underwent coronary angiography with a diagnosis of AMI at our hospital between March 2019 and September 2020. A total of 332 patients with AMI were enrolled; patients were divided into two groups according to their HbA1c levels: non-diabetic group (HbA1c <5.7%) and pre-diabetic group (5.7% ≤HbA1c <6.05%). The primary composite endpoints were cardiovascular death, myocardial infarction or stroke. Results: Of the 332 patients, 204 (61%) patients had non-diabetic groups, and 128 (39%) patients were between the pre-diabetic groups. During the follow-up period, the primary composite endpoints amounted to 7.4% and 15.6% in the non-diabetes and prediabetes group (p=0.026). The incidences of cardiovascular death and myocardial infarction were significantly higher in the prediabetic group than the nondiabetic group (p= 0.021, p=0.004; respectively). Independent predictors for the primary composite endpoints following the multivariate analysis included SYNTAX score (odds ratio [OR]: 0.912; %95 confidence interval [CI]: 0.832-0.999, p: 0.047), left ventricular ejection fraction (OR: 0.812; %95 CI: 0.753-0.876, p< 0.001), systolic blood pressure (OR: 0.955; %95 CI: 0.927-0.985, p: 0.003) and valuable categorical HbA1c ( 5.7% ≤HbA1c<6. 5% ) (OR: 2.787; %95 CI: 1.091-7.120, p: 0.032). Conclusion: Prediabetes group has been shown to have a higher incidence of the primary composite endpoints than non-diabetes. SYNTAX score, left ventricular ejection fraction, systolic blood pressure, and HbA1c (categorical variable) were found as independent predictors for the primary composite endpoint. Preventive measures in the stage of pre-diabetes might help the prevention of developing CVD.