Background: This study aimed to analyze survival rates among patients with acute coronary syndrome (ACS) covered and not covered by the National Comprehensive Care after Myocardial Infarction (KOS-Zawał) program.
Methods: A total of 179972 patients after myocardial infarction (MI) were enrolled in KOS-Zawał program between October 2017 and March 2020 and were included in the comparative analysis with survival analysis. A group of 24496 (13.61%) patients received KOS-Zawał services, while a group of 155476 (86.39%) were not covered by the KOS-Zawał program. The time points for observation of the incidence of death were set at 30, 180, and 365 days from the end of the first hospitalization.
Results: There was a lower incidence of death in favor of the KOS-Zawał group relative to the non-KOS-Zawał group both in hospital and at 30, 180, and 365 days after the end of hospitalization, respectively: 0.19% vs. 6.55%; 0.80% vs. 8.39%; 2.92% vs. 10.74%; and 6.35% vs. 13.40%. Survival analysis revealed a statistically significantly lower (P <0.0001) probability of death in the KOS-Zawał group compared with the non-KOS-Zawał group. Also, logistic regression analysis confirmed that patients in the KOS-Zawał group had a significantly lower risk of death than those in the non-KOS-Zawał group (odds ratio, 0.710; 95% confidence interval, 0.554-0.908; P = 0.007).
Conclusions: The KOS-Zawał comprehensive care program reduces the risk of death in the first year after MI by 29%. There are indications of a biased interpretation of the data due to the initial better clinical status of post-MI patients covered by the KOS-Zawał program.
Keywords: KOS-Zawał limitations; KOS-Zawał program; acute coronary syndrome; mortality risk; myocadiac infarction.