The Effect of Admission at Weekends on Clinical Outcomes in Patients with Non-ST-segment Elevation Acute Coronary Syndrome and Its Contributing Factors

We investigated the effects of weekend admission on adverse cardiac events in patients with non-ST-segment elevation acute coronary syndrome (NSTE-ACS). Patients with NSTE-ACS treated with percutaneous coronary intervention (PCI) were divided into a "weekend group" and a "weekday group" according to the emergency room arrival time. The primary outcome was 30-day major adverse cardiac events (MACE) including cardiac death, recurrent myocardial infarction, repeat revascularization, and urgent PCI. Of 577 patients, 168 patients were allocated to the weekend and 409 patients to the weekday group. The incidence of 30-day MACE was significantly higher in the weekend group (Crude: 15.5% vs. 7.3%, P = 0.005; propensity score matched: 12.8% vs. 4.8%, P = 0.041). After adjustment for all the possible confounding factors, in Cox proportional hazard regression analysis, weekend admission was associated with a 2.1-fold increased hazard for MACE (HR, 2.13; 95% CI, 1.26-3.60, P = 0.005). These findings indicate that weekend admission of patients with NSTE-ACS is associated with an increase in 30-day adverse cardiac event. GRAPHICAL ABSTRACT: [Image: see text]