Abstract
Background: The associations among various COPD efficacy endpoints are variable; however, the degree of correlation is often important in examining the consistency of the results across measures that are not considered redundant.
Objectives: Determine the correlations of improvements in lung function and CT analysis of lobar volume reduction (LoVR) to health outcomes following treatment of heterogeneous emphysema with BTVA.
Methods: Single-arm trial of BTVA in patients with upper lobe predominant emphysema. Patient criteria: FEV1 15% - 45% predicted, age 40-75 years, RV>150%, TLC>100%, 6 minute walk distance (6MWD)>140 m, DLCO>20%, previous pulmonary rehabilitation. Primary efficacy endpoints: FEV1 and St. George's Respiratory Questionnaire total score (SGRQ) at 6 months. Other endpoints: body plethysmography, mMRC dyspnea, 6MWD. Pearson correlation coefficients were calculated for the association of changes from baseline to 6 months of physiologic measures and LoVR to health outcomes.
Results: 44 patients received BTVA. Mean age: 63 years, men 50%, FEV1 0.86 (31% predicted), RV 237% predicted, DLCO 35% predicted, SGRQ 59 units, 6MWD 300 m, mMRC 2.9.
Conclusion: Physiologic and CT LoVR outcomes correlate strongest with the BODE score and the perception of dyspnea. The variable degree of correlation among the health outcomes indicates the need to examine multiple efficacy variables in emphysema and reinforce that the measures are not redundant.
- © 2011 ERS