Related Experiment Video
Updated: Apr 26, 2026

Autonomic Function Following Concussion in Youth Athletes: An Exploration of Heart Rate Variability Using 24-hour Recording Methodology
Published on: September 21, 2018
Duty-related risk of sudden cardiac death among young US firefighters
A Farioli1, J Yang2, D Teehan2
1Department of Environmental Health(Environmental & Occupational Medicine & Epidemiology), Harvard School of Public Health, Boston, MA 02115, USA, The Cambridge Health Alliance, Harvard Medical School, Cambridge, MA 02139, USA, Department of Medical and Surgical Sciences (DIMEC), University of Bologna, Bologna 40138, Italy.
Background:
Little is known regarding duty-related risks for sudden cardiac death (SCD) among young firefighters.
Aims:
To investigate duty-related SCD among US firefighters aged 45 or younger.
Methods:
We collected data on duty-related SCD from the US Fire Administration (USFA) and the US National Institute for Occupational Safety and Health (NIOSH). Two physicians independently reviewed each record. The proportions of time spent by firefighters performing specific duties were estimated from a municipal department, 17 large metropolitan departments and a national database. We estimated the duty-specific relative risks (RRs) and 95% confidence intervals (95% CI) of SCD relative to non-emergency duties based on the observed deaths and the expected average proportions of time per duty.
Results:
The USFA recorded 205 age-eligible on-duty SCDs between 1996 and 2012; 86 (42%) of these deaths and one additional SCD were investigated by NIOSH (total n = 206). NIOSH was more likely (P < 0.001) to report on SCD associated with physical training (69% of cases were investigated) and fire suppression (57%). Compared with non-emergency duties, the risk of SCD was increased for fire suppression (RR 22.1, 95% CI 14.8-32.9), alarm response (RR 2.6, 95% CI 1.5-4.6), alarm return (RR 4.1, 95% CI 2.7-6.2) and physical training (RR 4.8, 95% CI 3.2-7.2). RRs for SCD were higher among firefighters with a pre-existing history of a cardiac condition. All 16 SCDs associated with alarm response occurred among volunteer firefighters.
Conclusions:
The performance of strenuous emergency duties is strongly associated with an increased risk of SCD among young firefighters, particularly among those with a history of cardiovascular disease.
Related Concept Videos
Cardiopulmonary Resuscitation III: AED Use
Cardiopulmonary Resuscitation I: Adult
Coronary Artery Disease III: Clinical Manifestations
Introduction Cardiac Emergencies
Exercise and Cardiovascular Response
Light to moderate physical activity initiates a series of interconnected responses in the body. The heart rate modestly increases in anticipation of the workout, followed by widespread vasodilation as oxygen consumption by skeletal muscles increases. This results in decreased peripheral resistance, increased capillary blood flow, and accelerated...
Pneumothorax-I
Pneumothorax can be even further classified as spontaneous, traumatic, and tension pneumothorax.

