Increased 5-year risk of stroke, atrial fibrillation, acute coronary syndrome, and heart failure in out-of-hospital cardiac arrest survivors compared with population controls: A nationwide registry-based study

Abstract

Aim: Long-term risks of stroke, atrial fibrillation, or flutter (AF), acute coronary syndrome (ACS), and heart failure (HF) among survivors of out-of-hospital cardiac arrest (OHCA) are unknown. We aimed to examine 5-year risks of these outcomes among 30-day survivors of OHCA.

Methods: Thirty-day survivors of OHCA without a prior (or within 30 days after cardiac arrest) history of stroke, AF, ACS, or HF and population controls without a prior history of these conditions were identified using Danish nationwide registries. Five-year risks of stroke, AF, ACS, and HF standardized to the distributions of age, sex, and comorbidities among OHCA survivors and controls were obtained using multivariable regression.

Results: Of 4,362 30-day OHCA-survivors, 1,051 were stroke-, AF-, ACS-, and HF-naïve and matched with controls using age, sex, and time of OHCA event. Absolute five-year risks for OHCA survivors vs. controls were for stroke: 6.3% [95% confidence interval (CI) 4.1-8.5] vs. 2.0% [1.6-2.5], AF: 7.9% [5.7-10.2] vs. 2.6% [2.1-3.1], ACS: 5.0% [3.2-6.8] vs. 1.5% [1.1-1.9], and HF: 12.7% [10.1-15.4] vs. 1.2% [0.9-1.6], respectively. Corresponding relative risks were 3.18 [95% CI 1.76-4.61] for stroke, 3.03 [1.93-4.14] for AF, 3.23 [1.69-4.77] for ACS, and 10.40 [6.57-14.13] for HF.

Conclusion: When compared with population controls, OHCA survivors had significantly increased five-year risks of incident stroke, AF, ACS, and HF.

Keywords: Acute coronary syndrome; Atrial fibrillation and atrial flutter; Heart failure; Long-term risk; Out-of-hospital cardiac arrest survivors; Stroke.