Bronchodilator Responsiveness and Reported Respiratory Symptoms in an Adult Population

BackgroundThe relationship between patient-reported symptoms and objective measures of lung function is poorly understood. AimTo determine the association between responsiveness to bronchodilator and respiratory symptoms in random population samples. Methods4669 people aged 40 years and older from 8 sites in Canada completed interviewer-administered respiratory questionnaires and performed spirometry before and after administration of 200 ug of inhaled salbutamol. The effect of anthropometric variables, smoking exposure and doctor-diagnosed asthma (DDA) on bronchodilator responsiveness in forced expiratory volume in 1 second (FEV1) and in forced vital capacity (FVC) were evaluated. Multiple logistic regression was used to test for association between quintiles of increasing changes in FEV1 and in FVC after bronchodilator and several respiratory symptoms. ResultsDeterminants of bronchodilator change in FEV1 and FVC included age, DDA, smoking, respiratory drug use and female gender [p1 was associated with wheezing [p for trend ConclusionsBronchodilator responsiveness in FEV1 or FVC are associated with different respiratory symptoms in the community. Both flow and volume bronchodilator responses are useful parameters which together can be predictive of both wheezing and breathlessness in the general population.