Exercise-induced bronchoconstriction in female cleaners: effect of smoking

Abstract

Background. Airborne particles and pollutants, such as dust, tobacco smoke and automobile exhaust, are considered as stimulants that contribute to the development of exercise-induced bronchoconstriction (EIB). Objective. To evaluate prevalence of EIB and its relation to smoking in female cleaners. Methods. We performed a cross-sectional study including 43 female cleaners aged 26 to 57 (mean age 36.9±7.6), with duration of exposure 5 to 24 years (mean duration 11.6±5.5). In addition, 45 female office workers (aged 27 to 58, mean age 38.1±5.7) were studied as a control. Evaluation of exposed and unexposed workers included completion of a questionnaire, skin prick tests to common aeroallergens, spirometry, and constant submaximal exercise challenge test (ECT) on cycle ergometer. Results. We found similar EIB prevalence in both cleaners and office workers (9.3% vs. 6.7%; P=0.276). Bronchial reaction to exercise, expressed as a mean fall index FEV1, was significantly greater in ECT positive cleaners (23.4% vs. 16.1%, P=0.041). EIB was strongly linked to atopy and positive family history for asthma in both groups. EIB was non-significantly associated with daily smoking in office workers (P=0.276), whereas in cleaners that association just missed significance (P=0.074). Association between EIB and daily mean of cigarettes consumed was significant in smoking cleaners (P=0.039), whereas its association with smoking experience was non-significant in both groups. Bronchial reaction to exercise was significantly greater in exposed than in unexposed smokers (9.4% vs. 4.5%; P=0.036). Association of EIB with exand passive smoking was non-significant in both occupation groups. Conclusions. Our data suggest that daily smoking could interact with workplace exposure in development and severity of EIB in female cleaners.