Abstract 9502: Prehospital Variables Associated With Neurologically Intact Survival in Elderly Survivors After Out-of-Hospital Cardiac Arrest: Evidence from a Japanese Nationwide Population-based Cohort Study

Abstract

Introduction: Prehospital variables associated with neurologically intact survival in elderly survivors after out-of-hospital cardiac arrest (OHCA) are unclear and could differ according to age. Methods: We evaluated 6,349 elderly patients with OHCA (age ≥ 65 years) of cardiac origin who achieved prehospital return of spontaneous circulation (ROSC) and survived for at least 1-month after OHCA. Data were obtained from the prospectively recorded All-Japan Utstein Registry between 2011 and 2016. Patients witnessed by emergency medical service providers were excluded. The primary outcome was 1-month neurologically intact survival, defined as a cerebral performance category (CPC) score of 1-2. Patients were divided into three groups by age (65-74, 75-89, or ≥ 90 years). The time from call receipt to ROSC was calculated. Results: The rates of 1-month CPC 1-2 in patients aged 65-74, 75-89, and ≥ 90 years were 66.5% (2,079/3,125), 52.9% (1,557/2,943), and 42.7% (120/281), respectively (p for trend < 0.001). In multivariate logistic regression analysis, initial shockable rhythm and witnessed arrest were significantly associated with 1-month CPC 1-2 for all age groups (Table). However, the presence of bystander cardiopulmonary resuscitation (CPR) was significantly associated with 1-month CPC 1-2 only for patients aged 65-74 years. Time from call receipt to ROSC was not associated with 1-month CPC 1-2 for patients aged ≥ 90 years. In recursive partitioning analysis, the best single predictor for 1-month CPC 1-2 was initial shockable rhythm for all age groups. The next predictor for patients aged 65-74 years with initial shockable rhythm was the presence of bystander CPR, whereas the witnessed arrest was the next predictor for patients aged 65-74 years with initial non-shockable rhythm and other age groups regardless of the initial rhythm. Conclusions: Prehospital variables associated with neurologically intact survival in elderly survivors after OHCA varied with age.