Weekend effect on the mortality rate of in-hospital cardiopulmonary resuscitations from 2010 through 2019: a retrospective population-based cohort study

Abstract

Background: A smaller number of in-hospital medical staff and professionals on the weekend may lead to worsened survival outcomes in patients who have receive in-hospital cardiopulmonary resuscitation (ICPR). However, information regarding the effect of the weekend on survival outcomes after ICPR remains lacking. Therefore, we aimed to evaluate the “weekend effect” on the 6-month and 1-year mortality after ICPR. Methods: This population-based cohort study was based on data extracted from the National Health Insurance Service database in South Korea. We enrolled 298,676 adult (≥18 years old) patients who had experienced ICPR due to in-hospital cardiac arrest (IHCA) between January 1, 2010, and December 31, 2019. The primary endpoints were 6-month and 1-year mortality after ICPR. Propensity score matching (PSM) was used to adjust clinical covariates. Results: The survival analysis before and after PSM, 6-month mortality [pre-PSM hazard ratio (HR) =1.04, 95% confidence interval (CI): 1.03–1.04, P<0.001; post-PSM HR =1.02, 95% CI: 1.01–1.03, P<0.001], and 1 year mortality (pre-PSM HR =1.03, 95% CI: 1.03–1.04, P<0.001; post-PSM HR =1.02, 95% CI: 1.01–1.03, P<0.001) of the patients who received ICPR on weekends was higher than those on weekdays. The results of the multivariable Cox regression model for 1-year mortality among the entire cohort indicated that there were significant associations between high 1-year mortality after ICPR and the confounders (weekend vs. weekday: HR =1.04, 95% CI: 1.03–1.05, P<0.001). Conclusions: The “weekend effect” on ICPR survival outcomes lasted up to 1 year in South Korea. Fast-tracking development of a rapid cardiac intervention delivery system and employing an increased number of professionals on weekends can improve the weekend ICPR mortality rates. Further investigation is required into improvements that can be made to the current ICPR system.