Weekend Onset of Acute Myocardial Infarction Does Not Have a Negative Impact on Outcome in Japan

Abstract

Studies from North America indicate that patients admitted during the weekend with acute myocardial infarction (AMI) have a worse outcome than weekday-admitted patients, probably reflecting a lower rate of invasive procedures. However, it is unclear whether the same is true in Japan, which has a different healthcare system. Using the Japanese Acute Coronary Syndrome Study (JACSS) database, this study included 4,805 consecutive patients who were admitted within 48 h of onset of AMI (3,526 [73.4%] patients with weekday onset [Monday through Friday] and 1,279 [26.6%] with weekend onset [Saturday and Sunday]). There were no significant differences between the 2 groups in patient background and clinical features. The proportions of patients who underwent emergency catheterization (88.4% vs 88.0%) and reperfusion therapy (81.5% vs 81.4%) were also similar. There were no differences between the 2 groups in the in-hospital, 30-day, and 1-year mortality rates. Even after various adjustments, there was no difference in the risk of death associated with weekend versus weekday onset of AMI. There were no obvious differences in outcome for Japanese AMI patients in the weekday- or weekend-onset group, suggesting the quality of the Japanese healthcare system is similar for the entire week.