Off-hour admission and outcomes for patients with acute myocardial infarction undergoing percutaneous coronary interventions

Background Prior studies have suggested that patients with acute myocardial infarction (AMI) who are admitted during off-hours (weekends, nights and holidays) have higher mortality when compared with patients admitted during regular hours. Methods We analyzed consecutive patients with AMI (ST-elevation myocardial infarction [STEMI] and non-STEMI) who were treated with percutaneous coronary interventions from January 1998 to June 2010 at an academic medical center. Multivariable logistic regression models were used to estimate the association between off-hour admission and clinical outcomes adjusted for demographic and clinical variables. Results There were 3,422 and 2,664 patients with AMI admitted during off-hours and regular hours, respectively. Patients admitted during off-hours were more likely to have STEMI (56% vs 48%, P b .001), have cardiogenic shock at presentation (6% vs 4%, P = .002), and develop shock after presentation (6% vs 5%, P = .004). After multivariable analyses, off-hour admission was not significantly associated with in-hospital mortality (odds ratio [OR] 1.12, 95% CI 0.84-1.49), 30-day mortality (OR 1.12, 0.87-1.45), or 30-day readmissions (OR 1.01, 0.84-1.20) but was significantly associated with composite major complications and any of emergent coronary artery bypass graft surgery, ventricular arrhythmia, stroke/transient ischemic attack, and gastrointestinal/retroperitoneal/intracranial bleeding (OR 1.27, 1.05-1.55, P = .015). There was no significant time trend in the adjusted mortality difference between off-hours and regular hours. The results were not different between STEMI and non-STEMI. Conclusions Patients who were admitted during off-hours did not have higher mortality or readmission rates as compared with ones admitted during regular hours at an academic medical center. (Am Heart J 2015;169:62-8.).