The long-term rate of change in lung function in urban professional firefighters: a systematic review

Abstract

BackgroundDespite the known occupational hazards, it is not yet clear whether long-term career firefighting leads to a greater rate of decline in lung function than would normally be expected, and how this rate of change is affected by firefighting exposures and other risk/protective factors.MethodsA systematic search of online electronic databases was conducted to identify longitudinal studies reporting on the rate of change in the forced expiratory volume in one second (FEV1) of forced vital capacity (FVC). Included studies were critically appraised to determine their risk of bias using the Research Triangle Institute Item Bank (RTI-IB) on Risk of Bias and Precision of Observational Studies.ResultsTwenty-two studies were identified for inclusion, from four different countries, published between 1974 and 2016. Examined separately, studies were categorised by the type of firefighting exposure. Firefighters experienced variable rates of decline in lung function, which were particularly influenced by cigarette smoking. The influence of routine firefighting exposures is unclear and limited by the methods of measurement, while firefighters exposed to ‘non-routine’ severe exposures unanimously experienced accelerated declines.ConclusionsThe data provided by longitudinal studies provide an unclear picture of how the rate of change in lung function of firefighters relates to routine exposures and how it compares to the rate of change expected in a working-age population. Non-smoking firefighters who routinely wear respiratory protection are more likely than otherwise to have a normal rate of decline in lung function. Exposure to catastrophic events significantly increases the rate of decline in firefighter lung function but there is limited evidence detailing the effect of routine firefighting. Future studies will benefit from more robust methods of measuring exposure.Trial registrationInternational Prospective Register of Systematic Reviews (PROSPERO), registration number (CRD42017058499).

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

“…Acute airway inflammation has been documented 27. However, it remains unclear whether urban career firefighters without exposure to a non-routine disastrous event have an accelerated decline in pulmonary function 28. In our study, COPD mortality was significantly associated with cumulative fire-hours, after adjusting for employment duration.…”

Decreased Pulmonary Function Over 5 Years in US Firefighters

“…Heterogeneity and lack of excessive declines in pulmonary function in firefighters and associations with fire fighting duties have also been shown across cohorts. 14 , 27 , 34 , 35 Studies observing the Boston Fire Department from the late 1970s to the early 1980s found that firefighters who were not engaged in active firefighting duty also had large reductions in both FEV 1 and FVC, suggesting that other factors besides fire and smoke exposure promoted respiratory and pulmonary ailments. Additionally, these studies showed that firefighters who transitioned to less active assignments also had a greater decrement in ventilatory capacity than those who remained in fire-fighting positions.…”

“… 26 A systematic review of longitudinal changes in lung function among firefighters found non-smoking firefighters who routinely wore respiratory protection were more likely to have normal rates of decline in lung function. 27 Firefighters who reported “never or rarely” using their respiratory protection equipment during fire knockdown had a higher odds (odds ratio [OR]: 2.20; 95% confidence interval [CI]: 1.02 to 4.74) of accelerated FEV 1 decline (greater than 50 mL/yr) than those who “often or frequently” used their respiratory protection equipment. 40 The unprotected airway also provides an important exposure risk to carcinogens.…”

“…A recent systematic review of longitudinal changes in lung function in firefighters found high variability in the reported rates of decline, and the authors concluded that more evidence is needed on the effects of routine firefighting on lung function. 27 Therefore, the purpose of this study was to investigate changes in pulmonary function in a large cohort of career firefighters over a 5-year period using occupational medical records.…”

Will exposure to fire smoke at the Grenfell Tower fire cause long-term adverse health effects to firefighters of the London Fire Brigade?

“…A systematic review of the cumulative effects of firefighting on lung function has recently been published (3). It includes 22 studies whose findings are 'highly variable and provide an unclear picture of how the rate of change in lung function of firefighters relates to routine exposures; moreover the evidence for an 'exposure-response' relationship is not compelling'.…”