Mortality among acute myocardial infarction patients admitted to hospitals on weekends as compared with weekdays in Taiwan

Weekend effect has been considered to be associated with poorer quality of care and patient’s survival. For acute myocardial infarction (AMI) patients, the question of whether patients admitted during off-hours have worse outcomes as compared with patients admitted during on-hours is still inconclusive. We conducted this study to explore the weekend effect in AMI patients, using a nationwide insurance database in Taiwan. Using Taiwan National Health Insurance (NHI) claims database, we designed a retrospective cohort study, and extracted 184,769 incident cases of AMI through the NHI claims database between January 2006 and December 2014. We divided the patients into weekend admission group and weekday admission group. Patients were stratified as ST elevation/non-ST elevation AMI and receiving/not receiving percutaneous coronary intervention (PCI). We used a logistic regression model to examine the relative risk of in-hospital mortality and 1-year mortality which were obtained from the Taiwan National Death Registry between study groups. We found no difference between weekend group and weekday group for risk of in-hospital mortality (15.8% vs 16.2%, standardized difference 0.0118) and risk of 1-year mortality (30.2% vs 30.9%, standardized difference 0.0164). There was no statistically significant difference among all the comparisons through the multivariate logistic regression analysis adjusting for all the covariates and stratifying by the subtypes of AMI and whether or not executing PCI during hospitalization. As for AMI patients in Taiwan, admission on weekends or weekdays did not have a significant impact on either in-hospital mortality or 1-year cumulative mortality.