Mortality in a cohort of US firefighters from San Francisco, Chicago and Philadelphia: an update

Occup Environ Med. 2020 Feb;77(2):84-93. doi: 10.1136/oemed-2019-105962. Epub 2020 Jan 2.


Objectives: To update the mortality experience of a previously studied cohort of 29 992 US urban career firefighters compared with the US general population and examine exposure-response relationships within the cohort.

Methods: Vital status was updated through 2016 adding 7 years of follow-up. Cohort mortality compared with the US population was evaluated via life table analyses. Full risk-sets, matched on attained age, race, birthdate and fire department were created and analysed using the Cox proportional hazards regression to examine exposure-response associations between select mortality outcomes and exposure surrogates (exposed-days, fire-runs and fire-hours). Models were adjusted for a potential bias from healthy worker survivor effects by including a categorical variable for employment duration.

Results: Compared with the US population, mortality from all cancers, mesothelioma, non-Hodgkin's lymphoma (NHL) and cancers of the oesophagus, intestine, rectum, lung and kidney were modestly elevated. Positive exposure-response relationships were observed for deaths from lung cancer, leukaemia and chronic obstructive pulmonary disease (COPD).

Conclusions: This update confirms previous findings of excess mortality from all cancers and several site-specific cancers as well as positive exposure-response relations for lung cancer and leukaemia. New findings include excess NHL mortality compared with the general population and a positive exposure-response relationship for COPD. However, there was no evidence of an association between any quantitative exposure measure and NHL.

Keywords: cancer; dose-response; epidemiology; firefighters; longitudinal studies; mortality studies.

Publication types

  • Research Support, N.I.H., Intramural
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Cause of Death
  • Chicago / epidemiology
  • Cohort Studies
  • Female
  • Firefighters*
  • Humans
  • Leukemia / mortality
  • Lung Neoplasms / mortality
  • Lymphoma, Non-Hodgkin / mortality
  • Male
  • Mesothelioma / mortality
  • Mesothelioma, Malignant
  • Middle Aged
  • Neoplasms / mortality*
  • Occupational Diseases / mortality*
  • Occupational Exposure / adverse effects*
  • Occupations*
  • Philadelphia / epidemiology
  • Proportional Hazards Models
  • Pulmonary Disease, Chronic Obstructive / mortality
  • San Francisco / epidemiology
  • Young Adult