Clinical paper Long-term prognosis and causes of death among survivors after out-of-hospital cardiac arrest: A population-based longitudinal study

Abstract

Background: We aimed to identify the long-term prognosis and causes of death of out-of-hospital cardiac arrest (OHCA) survivors. Methods: Using claims data from the National Health Insurance Service (NHIS) database, we included 4937 OHCA patients (aged > 18 years) who were hospitalized between January 2005 and December 2015 and had survived for 30 days or more. The endpoints were long-term mortality and causes of death. Subgroup analyses were performed based on whether cardiac procedures were performed, and risk factors associated with cardiac and noncardiac deaths were identified. Results: We followed 4937 OHCA patients for a median of 3.3 years and up to 14 years of follow-up. The all-cause 1-, 3-, 5-, and 10-year cumulative mortality were 35.2%, 46.5%, 52.3%, and 62.7%, respectively. Regarding the 1130 OHCA survivors who had undergone cardiac procedures, the all-cause 1-, 3-, 5-, and 10-year cumulative mortality were 10.7%, 16.9%, 21.4%, and 30.6%, respectively. More patients (56.2%) died from noncardiovascular causes than from cardiovascular causes (43.8%) among the 2738 total patients who had died. The proportion of patients with cardiac death was significantly higher in the patient group with a cardiac procedure than in the group without a cardiac procedure (49.6% vs. 31.7%; P value < 0.001). A higher Charlson comorbidity index (CCI) was associated with an increased risk of cardiac mortality in the cardiac procedure group. Conclusions: The long-term mortality among OHCA survivors remains high, particularly within the first year. Individual characteristics are crucial for the follow-up of OHCA survivors and may help improve their long-term prognosis.