RT Journal Article SR Electronic T1 Paradoxical response to bronchodilators: Radiologic correlates and clinical implications JF European Respiratory Journal JO Eur Respir J FD European Respiratory Society SP 4634 VO 44 IS Suppl 58 A1 Surya Bhatt A1 James Wells A1 Victor Kim A1 Gerard Criner A1 Craig Hersh A1 Megan Hardin A1 William Bailey A1 Hrudaya Nath A1 Douglas Stinson A1 Carla Wilson A1 Barry Make A1 Mark Dransfield YR 2014 UL http://erj.ersjournals.com/content/44/Suppl_58/4634.abstract AB BackgroundBronchodilator response is seen in a significant proportion of patients with chronic obstructive pulmonary disease (COPD). However, there are also reports of a paradoxical response to bronchodilators, resulting in bronchoconstriction and significant respiratory distress. Asymptomatic bronchoconstriction is likely far more common; however there has been no systematic study of this paradoxical response (PR).MethodsSubjects from a large multicenter study (COPDGene) that included current and former smokers, were categorized into two groups based on PR defined as at least a 12% and 200ml reduction in FEV1 and/or FVC post-bronchodilator.Results:9986 subjects were included. PR was seen in 4.54%, and the frequency was similar in those with COPD and smokers without airflow obstruction. Those with PR were younger, more likely to be current smokers, and had worse airflow obstruction. Compared to Caucasians, PR was twice as common in African Americans (6.9% vs. 3.4%;p <0.001). On multivariate analyses, African American race (adjusted OR 1.89, 95%CI 1.50 to 2.39), reduced emphysema (OR 0.996,95%CI 0.992 to 0.999) and increased wall area% of segmental airways (OR 1.04,95%CI 1.01 to 1.08) were independently associated with PR. PR was also independently associated with worse dyspnea, lower six minute walk distance, higher BODE index, and greater frequency of exacerbations (adjusted RR 1.33, 95%CI 1.06 to 1.66). These relationships held true when PR was defined by other %FEV1 change criteria.ConclusionsParadoxical response to bronchodilators is associated with distinct clinical and radiologic features, and may represent a novel COPD phenotype associated with worse outcomes.