title: Duty-related risk of sudden cardiac death among young US firefighters.
abstract: BACKGROUND
  Little is known regarding duty-related risks for sudden cardiac death (SCD) among young firefighters.
  
  
  OBJECTIVE
  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.
authors.affiliation: Department 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.
authors.forename: A
authors.initials: A
authors.lastname: Farioli
authors.affiliation: Department 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.
authors.forename: J
authors.initials: J
authors.lastname: Yang
authors.affiliation: Department 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.
authors.forename: D
authors.initials: D
authors.lastname: Teehan
authors.affiliation: Department of Environmental Health(Environmental & Occupational Medicine & Epidemiology), Harvard School of Public Health, Boston, MA 02115, USA, Interdisciplinary for Hormone and Metabolic Disorders, Endokrinologikum ULM, 89073 Ulm, Germany.
authors.forename: D M
authors.initials: DM
authors.lastname: Baur
authors.affiliation: Department of Health and Exercise Sciences, Skidmore College, Saratoga Springs, New York, NY 12866, USA.
authors.forename: D L
authors.initials: DL
authors.lastname: Smith
authors.affiliation: Department 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, skales@hsph.harvard.edu.
authors.forename: S N
authors.initials: SN
authors.lastname: Kales
mesh_terms: D000328:Adult; D002318:Cardiovascular Diseases / Q000150:complications / Q000401:mortality*; D016757:Death, Sudden, Cardiac / Q000209:etiology; D004630:Emergencies; D005260:Female; D061388:Firefighters / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D009314:National Institute for Occupational Safety and Health, U.S.; D009784:Occupational Diseases / Q000209:etiology / Q000401:mortality*; D016272:Occupational Health / Q000706:statistics & numerical data*; D018635:Rescue Work; D012307:Risk Factors; D014481:United States / Q000453:epidemiology; D014940:Work Schedule Tolerance
keywords: Firefighters; longitudinal study; occupational disease; occupational exposure; sudden cardiac death.
references.citation: Med Sci Sports Exerc. 2011 Sep;43(9):1752-9
references.pmid: 21364484
references.citation: J Occup Environ Med. 2006 Oct;48(10):1047-53
references.pmid: 17033504
references.citation: Med Sci Sports Exerc. 2014 Mar;46(3):448-54
references.pmid: 23924919
references.citation: Ergonomics. 2013;56(9):1465-73
references.pmid: 23869685
references.citation: Cardiol Rev. 2011 Jul-Aug;19(4):202-15
references.pmid: 21646874
references.citation: N Engl J Med. 2007 Mar 22;356(12):1207-15
references.pmid: 17377158
references.citation: Extrem Physiol Med. 2013 Feb 01;2(1):6
references.pmid: 23849605
references.citation: J Occup Med. 1981 Nov;23(11):762-6
references.pmid: 7320775
references.citation: Am J Cardiol. 2008 Mar 1;101(5):585-9
references.pmid: 18308003
references.citation: J Obes. 2012;2012:908267
references.pmid: 22888409
references.citation: Environ Health. 2003 Nov 06;2(1):14
references.pmid: 14613487
references.citation: Am J Cardiol. 2013 Dec 15;112(12):1962-7
references.pmid: 24079519
references.citation: J Strength Cond Res. 2002 May;16(2):271-7
references.pmid: 11991781
references.citation: J Occup Med. 1975 Apr;17(4):247-50
references.pmid: 1127475
references.citation: BMJ. 2012 Jul 26;345:e4800
references.pmid: 22835925
references.citation: J Am Coll Cardiol. 2013 Mar 12;61(10):1027-40
references.pmid: 23473408
references.citation: Occup Med (Lond). 2014 Jun;64(4):228-30
references.pmid: 24850812
references.citation: PLoS One. 2014 Feb 04;9(2):e87539
references.pmid: 24503596
references.citation: Am J Cardiol. 2009 Nov 15;104(10):1441-5
references.pmid: 19892065
references.citation: N Engl J Med. 2018 Jun 21;378(25):2441-2442
references.pmid: 29897867
references.citation: NFPA J. 1996 Jul-Aug;90(4):63-5, 68-70, 77
references.pmid: 10158564
references.citation: Occup Med (Lond). 2012 Oct;62(7):566-9
references.pmid: 22826554
references.citation: Neurosci Biobehav Rev. 2009 Feb;33(2):63-70
references.pmid: 18534677
references.citation: Eur Heart J. 2008 Aug;29(15):1881-8
references.pmid: 18534976