Effects of Prediabetes on Long-term Risk of Developing Cardiac Events in Patients Presenting With Acute Coronary Syndrome.

Objectives: The aim of this work was to identify the long-term risk associated with prediabetes and developing subsequent cardiac events in patients presenting with acute coronary syndrome (ACS) at a tertiary health-care centre.

Methods: In this retrospective cohort study, we analyzed patients admitted with ACS between January and December 2013. Two hundred thirty patients with prediabetes were matched to a comparison cohort of patients with no diabetes based on age, sex, and diagnosis code of the International Statistical Classification of Diseases and Related Health Problems---10th revision. The primary outcome was incidence of ACS readmission over a 5-year period.

Results: There were 46 (20%) readmissions for ACS in the prediabetes cohort and 33 (14.3%) in the no-diabetes cohort. Univariable conditional logistic regression showed that prediabetes was not a significant risk factor for ACS readmission (odds ratio, 1.481; 95% confidence interval, 0.909 to 2.414; p=0.115). After accounting for other major risk factors for coronary disease, prediabetes was not shown to be a significant risk factor for ACS readmission (odds ratio, 1.333; 95% confidence interval, 0.795 to 2.233; p=0.276).

Conclusions: Among patients presenting with ACS, prediabetes was not associated with increased risk of readmission for subsequent cardiac events compared with patients with no diabetes after 5 years of follow-up. A longer follow-up duration is needed.