Weekend Effect in the Management and Outcomes of Acute Myocardial Infarction in the United States, 2000-2016

OBJECTIVE: To assess the effects of weekend admission vs weekday admission on the management and outcomes of acute myocardial infarction (AMI). METHODS: Adult ST-segment elevation myocardial infarction (STEMI) and non-STEMI (NSTEMI) hospital admissions were identified using the National (Nationwide) Inpatient Sample (2000-2016). Interhospital transfers were excluded. Timing of coronary angiography (CA) and percutaneous coronary intervention (PCI) relative to the day of admission was identified. Outcomes of interest included in-hospital mortality, receipt of early CA, timing of CA and PCI, resource utilization, and discharge disposition for weekend vs weekday admissions. RESULTS: Of the 9,041,819 AMI admissions, 2,406,876 (26.6%) occurred on weekends. Compared with 2000, in 2016 there was an increase in weekend STEMI (adjusted odds ratio [aOR], 1.12; 95% CI, 1.08-1.16; P<.001) but not NSTEMI (aOR, 1.01; 95% CI, 0.98-1.02; P=.21) admissions. Compared with weekday admissions, weekend admissions received comparable CA (59.9% vs 58.8%) and PCI (38.4% vs 37.6%) and specifically lower rates of early CA (hospital day 0) (26.0% vs 20.8%; P<.001). There was a steady increase in CA and PCI use during the 17-year period. Mean ± SD time to CA was higher in the weekend group vs the weekday group (1.2±1.8 vs 1.0±1.8 days; P<.001). Weekend admission did not influence in-hospital mortality (aOR, 1.01; 95% CI, 1.00-1.01; P=.05) but had fewer discharges to home (58.7% vs 59.7%; P<.001). CONCLUSION: Despite small differences in CA and PCI, there were no differences in in-hospital mortality of AMI admissions on weekdays vs weekends in the United States in the contemporary era.