Out-of-hospital cardiac arrest in the elderly: A large-scale population-based study.

BACKGROUND: There is little information on elderly people who suffer from out-of-hospital cardiac arrest (OHCA).

AIM: To determine 30-day mortality and neurological outcome in elderly patients with OHCA.

METHODS: OHCA patients ≥ 70 years of age who were registered in the Swedish Cardiopulmonary Resuscitation Register between 1990 and 2013 were included and divided into three age categories (70-79, 80-89, and ≥ 90 years). Multiple logistic regression analyses were performed to identify independent predictors of 30-day survival.

RESULTS: Altogether, 36,605 cases were included in the study. Thirty-day survival was 6.7% in patients aged 70-79 years, 4.4% in patients aged 80-89 years, and 2.4% in those over 90 years. For patients with witnessed OHCA of cardiac aetiology found in a shockable rhythm, survival was higher: 20%, 15%, and 11%, respectively. In 30-day survivors, the distribution according to the cerebral performance categories (CPC) score at discharge from hospital was similar in the three age groups. In multivariate analysis, in patients over 70 years of age, the following factors were associated with increased chance of 30-day survival: younger age, OHCA outside the home, witnessed OHCA, CPR before arrival of EMS, shockable first-recorded rhythm, and short emergency response time.

CONCLUSIONS: Advanced age is an independent predictor of mortality in OHCA patients over 70 years of age. However, even in patients above 90 years of age, defined subsets with a survival rate of more than 10% exist. In survivors, the neurological outcome remains similar regardless of age.