Effect of Yearly Number of Fires Fought on Risk for Atrial Fibrillation in Firefighters

A firefighter emerges from a thick cloud of smoke while battling the Kincade Fire along Chalk Hill Road in Healdsburg, California on October 27, 2019. – Powerful winds were fanning wildfires in northern California in “potentially historic fire” conditions, authorities said October 27, as tens of thousands of people were ordered to evacuate and sweeping power cuts began in the US state. (Photo by Philip Pacheco / AFP) (Photo by PHILIP PACHECO/AFP via Getty Images)
A study assessed the relationship between atrial fibrillation and occupational exposure in patients employed as firefighters.

A survey found that firefighters may be at higher risk for atrial fibrillation (AF) as the number of fires they fight per year increases. These findings were published in the Journal of the American Heart Association.

Firefighters who had affiliations with 5 national or international professional organizations were contacted by email and a link to participate in the study was put on the organization’s website. Active firefighters (n=10,860) were asked to complete a survey which assessed demographics, occupational history, cardiovascular and health history, and annual of exposure to fires. Non-firefighter participants or retired firefighters were recruited by their firefighter family members and were surveyed as the control group. Risk factors for AF, stroke, and transient ischemic attack (TIA) were evaluated.

Firefighters in the study were 93.5% men; 95.5% were aged 60 years or older; 92.2% were White, American Indian, or Alaskan Native; 89% were career firefighters; and 15.4% had prior military experience.

AF was self-reported among 2.9% of men and 0.9% of women (P =.005). In all cases, the prevalence of AF was higher among individuals who reported having comorbidities (all P £.042).

Stratified by the number of fires fought per year, a linear positive relationship was observed between fires fought and lifetime prevalence of AF (0-5 fires: 2.01% vs ³31 fires: 4.55%) but not with stroke or TIA (0-5 fires: 0.72% vs ³31 fires: 0.76%).

Significant predictors for AF included being a man (adjusted odds ratio [aOR], 2.98; 95% CI, 1.22-7.25; P =.017), history of hypertension (aOR, 2.75; 95% CI, 2.13-3.53; P <.001), obstructive sleep apnea (aOR, 1.89; 95% CI, 1.44-2.48; P <.001), and number of fires fought per year (aOR, 1.14; 1.04-1.25; P =.006). Younger age (<60 years; aOR, 0.50; 95% CI, 0.34-0.73; P <.001) and alcohol use (aOR, 0.68; 95% CI, 0.52-0.89; P =.004) decreased risk for AF.

Predictors of stroke or TIA included traditional risk factors such as AF, diabetes, hypertension, anticoagulation use, and age (all P £.043) and not number of fires fought (aOR, 1.01; 95% CI, 0.85-1.2; P =.898).

This study may have been limited by relying on self-reported health status and by grouping retired firefighters with non- firefighters as the control group.

“Through survey-based collection of data from over 10,000 respondents, this study has shown that increased prevalence of AF in [firefighters] is associated with increased exposure to the firefighting environment,” the researchers noted. “Further research into causal relationships, underlying mechanisms, and risk mitigation strategies is crucial and will lead to a better understanding of cardiovascular risk factors in [firefighting] and the ability to protect and care for [firefighters] in the line of duty.”


Vanchiere C, Thirumal R, Hendrani A, et al. Association between atrial fibrillation and occupational exposure in firefighters based on self-reported survey data. J Am Heart Assoc. Published online March 23, 2022. doi:10.1161/JAHA.121.022543