CORRECTED March 30, 2023 // An earlier version of this article incorrectly listed "endobrachial valves" in the headline and the fourth paragraph, instead of "endobronchial valves."
Independent of pulmonary function, improvement in exercise capacity and quality of life after lung volume reduction using endobronchial valves (EBV) are associated with a significant survival benefit, according to study results published in Respiratory Medicine. The benefits were independent of reduction in target lobe volume or the presence of a complete lobar atelectasis.
In patients with more severe chronic obstructive pulmonary disease (COPD), the usual treatments of smoking cessation, pharmacological therapy, pulmonary rehabilitation aiming for symptom reduction, minimizing the burden of disease, slowing disease progression, and improving exercise tolerance fall short according to Sharyn A. Roodenburg, PhD candidate in the department of pulmonary diseases, University of Groningen (the Netherlands), and colleagues.
Lung volume reduction is generally reserved for patients with COPD that has a predominantly emphysematous phenotype and severely hyperinflated lungs. While both surgical and bronchoscopic lung volume reduction (BLVR) approaches are in use, bronchoscopic approaches are less invasive and incur lower morbidity. When technically feasible, they are generally preferred over open surgery.
BLVR using endobronchial valves (EBV), the most effective and commonly employed technique, has been shown in randomized controlled trials to improve pulmonary function, exercise capacity, and health-related quality of life.
Noting a survival benefit in prior studies among patients with complete lobar atelectasis following treatment, the authors wrote that their own clinical experience has been that significant treatment responses (pulmonary function and/or exercise capacity) observed in patients with a partial lobar atelectasis may also be associated with a survival benefit. Their aim was to evaluate whether pulmonary function, radiological, health-related quality of life, and/or exercise capacity outcome responders to EBV treatment have a survival benefit over nonresponders.
Their analysis included data collected prospectively out of four clinical trials (CHARTIS, STELVIO, IMPACT, and LIBERATE) from June 2008 to Dec. 2020 at the University Medical Center Groningen. Predetermined potential predictors of survival included change in forced expiratory volume in 1 second (FEV1), change in residual volume (RV), change in RV/total lung capacity (RV/TLC) ratio, change in 6-minute walk distance (6MWD), change in total score on the St. George’s Respiratory Questionnaire (SGRQ), target lobe volume reduction (TLVR), and presence of complete lobar atelectasis (defined as a TLVR of 100%).
Mean age was 61.3 years among the 428 included patients (68% women). Data on both the 6MWD and SGRQ total score at baseline and 1-year follow-up were available for 252 patients. SGRQ decreased by 8.3 points or more, and 6MWD increased by 26 meters or more over baseline. Among these patients, 113 (45%) were responders on both 6MWD and SGRQ, 49 (19%) patients were responders on 6MWD only, 31 (12%) patients on SGRQ only, and 59 (23%) were nonresponders on both. Survival was significantly worse among nonresponders on 6MWD, SGRQ, or on both. 6MWD and SGRQ response were independent predictors for improved survival time (hazard ratio, 0.50; 95% confidence interval, 0.28-0.89; P = .02 and HR, 0.54; 95% confidence interval, 0.30-0.94; P = .03, respectively). Survival was not significantly affected by the presence of complete lobar atelectasis or pulmonary function improvements.
"Especially in patients with a low FEV1 (< 50% predicted), 6-minute walk distance was found to be a better predictor for mortality than pulmonary function. A possible explanation for why change in 6-minute walk distance is a better predictor for survival after EBV treatment than the change in pulmonary function and hyperinflation might be that the 6-minute walk distance not only reflects the pulmonary limitation of these patients, but also captures the extrapulmonary manifestations of COPD, such as cardiac dysfunction, musculoskeletal disorders, fatigue, and psychological symptoms, all of which can impact survival," the authors noted.
The study received no funding, and the authors did not report any disclosures.
This story originally appeared on MDedge.com, part of the Medscape Professional Network.
Lead image: The National Institute of Health
Cite this: Exercise Capacity and QOL Linked to Significant Survival Benefit With Endobronchial Valves - Medscape - Mar 24, 2023.