Abstract 4001: Differences in Mortality between Weekend and Weekday Admission for Acute Myocardial Infarction (A 16-Year New Jersey Statewide Study)
Background Patients with acute myocardial infarction need urgent diagnostic procedures and therapeutic interventions that are often less likely to be available on weekends.
Methods Using the Myocardial Infarction Data Acquisition System (MIDAS), we studied the differences in mortality among 231,164 patients admitted for first acute myocardial infarction by whether the admission occurred on a weekend or weekday. All admissions to non-federal hospitals in New Jersey from 1987 to 2002 were included.
Results Patients admitted on weekends were less likely to have cardiac catheterization, percutaneous interventions, and coronary artery bypass graft, especially in the first and second day of hospitalization (p<0.0001). This effect was magnified in more recent years. In patients admitted from 1999–2002 (N=59,786), mortality at 30 days after admission was significantly higher for patients admitted on weekends (12.9% vs. 12.0%, p=0.0055). The difference became significant the day after admission (3.3% vs. 2.7%, p=0.0002) and persisted at one year (1% absolute mortality difference). The higher 30-day mortality remained statistically significant after adjustment for demographics, site of the infarction, and comorbidities (Relative Risk 1.048, 95% CI 1.022–1.076, p=0.0004). This difference became weaker and statistically insignificant after additional adjustment for invasive cardiac procedures (RR 1.023, 95% CI 0.997–1.049, p=0.0904), implying that a lower rate of invasive procedures may be in part responsible for the difference in mortality.
Conclusions Patients admitted on weekends had lower use of invasive cardiac procedures and higher mortality. This implies that better staffing on weekends or regionalization of care may improve the outcome of patients with acute myocardial infarction.