Exercise-related out-of-hospital cardiac arrest in Victoria, Australia

Characteristics and outcomes of exercise-related out-of-hospital cardiac arrests (OHCA) are not well described in Australia.

This was a retrospective observational study of non-exercise-related aetiology and exercise-related OHCAs from the Victorian Ambulance Cardiac Arrest Registry between 2008 and 2016, including 12-month quality of life data from 2010 to 2016. Exercise-related OHCA was defined as taking place during or within 1 h of at least moderate intensity exercise. Descriptive statistics and adjusted logistic regression analyses were performed.

During the study period there were 482 exercise-related and 33,358 non-exercise-related OHCAs. Jogging/running were the most frequent precipitating sports. The incidence rate of exercise-related OHCA was low (<1 per 100,000 person-years). Compared to non-exercise-related aetiology, exercise-related OHCAs were younger (mean 54 versus 70 years, p < 0.001) and more likely to present in an initial shockable rhythm (85% versus 18%, p < 0.001). Bystander CPR, and bystander or EMS defibrillation at any time, were more common among exercise-related arrests (93% versus 38%, p < 0.001 and 91% versus 24%, p < 0.001, respectively). A public access defibrillator was used in 24% of shockable exercise-related OHCAs compared with 4% of non-exercise-related OHCAs (p < 0.001). After adjustment for arrest characteristics, exercise-related OHCAs were more likely to survive to hospital discharge (50% versus 14%, p < 0.001; adjusted odds ratio [AOR] = 1.56, 95% confidence interval [CI] 1.25-1.96, p < 0.001) and survive to 12-months with good functional recovery (72% versus 62%, p = 0.012; AOR = 1.57, 95% CI 1.08-2.28, p = 0.018).

Exercise-related OHCAs were associated with better short- and long-term prognoses compared to non-exercise-related OHCAs. The underlying factors associated with this survival benefit warrant further investigation.