Changes in Therapeutic Hypothermia and Coronary Intervention Provision and In-Hospital Mortality of Patients With Out-of-Hospital Cardiac Arrest: A Nationwide Database Study*

Objectives: To evaluate the change in provision of therapeutic hypothermia and coronary intervention (postresuscitation care) over time and to clarify the association between these provisions and in-hospital mortality in patients with out-of-hospital cardiac arrest. Design: A nationwide retrospective cohort study using multiple propensity score analyses. Setting: Japanese Diagnosis Procedure Combination inpatient database. Patients: Adult patients with cardiogenic out-of-hospital cardiac arrest related to ventricular fibrillation were identified from July to December in 2008-2012 (385 hospitals; n = 3,413). Measurements and Main Results: We evaluated the proportion of patients receiving postresuscitation care and all-cause mortality at 30 days after out-of-hospital cardiac arrest. The proportion of postresuscitation care provision increased significantly over the study period (Mantel-Haenszel trend test, p < 0.001). The overall 30-day mortality was 52.0% (1,774/3,413), and the crude 30-day mortality decreased significantly during the study period (p = 0.006). Logistic regression analysis showed significant associations between the fiscal years 2011 and 2012 and 30-day mortality (2011: odds ratio, 0.75; 95% CI, 0.57-0.98 and 2012: odds ratio, 0.61; 95% CI, 0.47-0.81). Multiple propensity score analysis incorporating postresuscitation care showed that 30-day mortality was significantly associated with postresuscitation care, and the significant associations between 30-day mortality and the years 2011 and 2012 were no longer observed (2011: odds ratio, 1.05; 95% CI, 0.82-1.3 and 2012: odds ratio, 0.95; 95% CI, 0.74-1.2). Conclusions: The 30-day survival rate of adult patients with cardiogenic out-of-hospital cardiac arrest related to ventricular fibrillation improved significantly after 2010 in Japan. This improvement may be associated with an increase in postresuscitation care provision.