Neurologic Recovery at Discharge and Long-Term Survival After Cardiac Arrest

Importance Brain injury is the leading cause of death following cardiac arrest and is associated with severe neurologic disabilities among survivors, with profound implications for patients and their families, as well as broader societal impacts. How these disabilities affect long-term survival is largely unknown. Objective To investigate whether complete neurologic recovery at hospital discharge after cardiac arrest is associated with better long-term survival compared with moderate or severe neurologic disabilities. Design, Setting, and Participants This cohort study used data from 4 mandatory national registers with structured and predefined data collection and nationwide coverage during a 10-year period in Sweden. Participants included adults who survived in-hospital cardiac arrest (IHCA) or out-of-hospital cardiac arrest (OHCA) beyond 30 days and who underwent predefined neurologic assessment conducted by health care professionals at hospital discharge using the Cerebral Performance Category (CPC) scale between January 2010 and December 2019. Patients were divided into 3 categories: complete recovery (CPC 1), moderate disabilities (CPC 2), and severe disabilities (CPC 3-4). Statistical analyses were performed in December 2023. Exposure CPC score at hospital discharge. Main Outcomes and Measures The primary outcome was long-term survival among patients with CPC 1 compared with those with CPC 2 or CPC 3 or 4. Results A total of 9390 cardiac arrest survivors (median [IQR] age, 69 .0 [58.0-77.0] years; 6544 [69.7%] male) were included. The distribution of functional neurologic outcomes at discharge was 7374 patients (78.5%) with CPC 1, 1358 patients (14.5%) with CPC 2, and 658 patients (7.0%) with CPC 3 or 4. Survival proportions at 5 years were 73.8% (95% CI, 72.5%-75.0%) for patients with CPC 1, compared with 64.7% (95% CI, 62.4%-67.0%) for patients with CPC 2 and 54.2% (95% CI, 50.6%-57.8%) for patients with CPC 3 or 4. Compared with patients with CPC 1, there was significantly higher hazard of death for patients with CPC 2 (adjusted hazard ratio [aHR], 1.57 [95% CI, 1.40-1.75]) or CPC 3 or 4 (aHR, 2.46 [95% CI, 2.13-2.85]). Similar associations were seen in the OHCA and IHCA groups. Conclusions and Relevance In this cohort study of patients with cardiac arrest who survived beyond 30 days, complete neurologic recovery, defined as CPC 1 at discharge, was associated with better long-term survival compared with neurologic disabilities at the same time point.