The Lung Function of Male Metropolitan Fire-Fighters Compared To General Population Controls
Presentation at Research Forum of the 2012 Bushfire CRC and AFAC Annual Conference.
The spirometer, which is used to measure lung capacity, was invented in the mid-19th Century. London Fire fighters are reported to be amongst the first people to have their lung function assessed using this new technology in 1846. More recently spirometry results were used to highlight the effects of exposures in New York Fire-fighters during the 9/11 disaster. The main objectives of this study were to compare changes in lung function over time between male metropolitan fire-fighters and general population controls, and to investigate associations between fire-fighters' use of respiratory protection devices and accelerated lung function decline.
Methods – A 3-year longitudinal comparison of FEV1 (forced expiratory volume in 1 second) and forced vital capacity (FVC) between 281 fire-fighters and 933 population controls from the North West Adelaide Health Study. Repeated measures and logistic regression models were used to compare FEV1 and FVC and risk of accelerated (>0.050 L/year) FEV1 decline between the cohorts. Within the fire-fighter cohort, risk of accelerated FEV1 decline was compared between subgroups based on use of respiratory protection devices.
Results – Population controls showed very similar mean annual declines for FEV1 and FVC across age categories. Fire-fighters had a lower FEV1 decline compared to controls (OR=0.60, 95%CI 0.44; 0.83), however, fire-fighters who never or rarely used respiratory protection during fire knockdown had an accelerated FEV1 decline compared to those who used it often or frequently (OR=2.20, 95%CI 1.02; 4.74).
Conclusions – Younger fire-fighters showed an increase in lung function relative to their older colleagues, while population controls consistently showed decline of lung function across all ages. Fire-fighters who reported to never or rarely use their respiratory protection had an increased risk of accelerated FEV1 decline. This study further highlights the importance of consistent use of respiratory protection devices by fire-fighters and monitoring of their (respiratory) health.