Bronchodilator response in healthy subjects

Background: The ATS/ERS Task Force (Eur Respir J 2005; 26:948-968) recommends an increase of both 12% and 200 mL in FEV1 or FVC to define a positive bronchodilator (+BD) response. These criteria are based largely on expert opinion. We aimed to describe the BD response response characteristics of the COPDGene non-smoking, healthy cohort. Methods: We evaluated 422 non-smoking, healthy adult patients with acceptable and repeatable spirograms obtained before and after (pre- and post-BD) two inhalations of albuterol (200 mcg) at 21 COPDGene sites. The same equipment (ndd, Zucih, Switzerland) and methodologies were used at each site. We determeined the mean, SD and 95th percentile for absolute (mL) and percent (%) differences between pre-BD and post-BD for FEV1, FVC and FEV6. We also determined the number of subjects that met current ATS/ERS Task Force recommendations for +BD response. Results: The mean, SD and 95th percentile for absolute and percent differences between pre-BD and post-BD mean are shown (Table). The percent of subjects that met ATS/ERS Task Force recommendations for +BD response for FEV1 was 5.7% and for FVC was 5.2%. Conclusion: Our results indicate that in a healthy adult population, a significant BD response for FEV1 is approximately 200 mL and 9%; corresponding values for FVC are 200 mL and 6%. Our results are in agreement with the ATS/ERS Task Force recommendation for an absolute increase in FEV1 and FVC (200 mL) to define a +BD response but suggest that the 12% increase criteria for FEV1 and FVC is too large.