The relationship between age and outcome in out-of-hospital cardiac arrest patients

Abstract

Aim: To determine the association between age and outcome in a large multicenter cohort of out-of-hospital cardiac arrest patients.

Methods: Retrospective, observational, cohort study of out-of-hospital cardiac arrest from the CARES registry between 2006 and 2013. Age was categorized into 5-year intervals and the association between age group and outcomes (return of spontaneous circulation (ROSC), survival and good neurological outcome) was assessed in univariable and multivariable analysis. We performed a subgroup analysis in patients who had return of spontaneous circulation.

Results: A total of 101,968 people were included. The median age was 66 years (quartiles: 54, 78) and 39% were female. 31,236 (30.6%) of the included patients had sustained ROSC, 9761 (9.6%) survived to hospital discharge and 8058 (7.9%) survived with a good neurological outcome. The proportion of patients with ROSC was highest in those with age <20 years (34.1%) and lowest in those with age 95-99 years (23.5%). Patients with age <20 years had the highest proportion of survival (16.7%) and good neurological outcome (14.8%) whereas those with age 95-99 years had the lowest proportion of survival (1.7%) and good neurological outcome (1.2%). In the full cohort and in the patients with ROSC there appeared to be a progressive decline in survival and good neurological outcome after the age of approximately 45-64 years. Age alone was not a good predictor of outcome.

Conclusions: Advanced age is associated with outcomes in out-of-hospital cardiac arrest. We did not identify a specific age threshold beyond which the chance of a meaningful recovery was excluded.

Keywords: Age; Cardiac arrest; Out-of-hospital cardiac arrest; Outcome; Predictor.