The Impact of the Time of Admission on Baseline Mortality Risk in Patients with ST Elevation Myocardial Infarction

Abstract

Introduction: Prior studies have reported a differential mortality effect of the time of admission (weekdays vs. weekends, regular hours vs. off hours) in patients with ST elevation myocardial infarction (STEMI). However, these studies did not evaluate the relationship between the admission hours and mortality risk at admission. Patients and Methods: A total of 228 patients presenting with reperfusion eligible acute STEMI between January 2006 and March 2009 were enrolled in this study. With respect to admission hours, patients were divided into 4 groups: night (between 24.00 and 05.59 hours), morning (between 06.00 and 11.59 hours), afternoon (between 12.00 and 17.59 hours) and evening (between 18.00 and 23.59 hours)]. The relationship between admission hours and in hospital mortality risk were examined using the TIMI risk index (TRI) [heart rate x (age/10)2 /systolic blood pressure]. Results: Patients in different groups of admission hours were not significantly different in terms of age, heart rate, systolic blood pressure, Killip class > 1 or time to infarction. TRI, a predictor of in-hospital mortality, was also not significantly different between these groups defined using 6-hour time intervals (p: 0.69). Conclusion: Time of admission did not significantly affect the mortality risk at presentation in patients with STEMI. Healthcare providers should continue to work to enhance the healthcare system during regular and off-hours and to reduce existing disparities in cardiac care through multifaceted initiatives aiming to improve the timely delivery of evidence-based therapies.