Comparative analysis of pulmonary function decline in patients undergoing bronchoscopic lung volume reduction with endobronchial valves versus conservative treatment in emphysema management: A longitudinal coarsened exact matched analysis

BackgroundChronic obstructive pulmonary disease (COPD) and emphysema display a chronic and progressive disease for the individual patient. The forced expiratory volume in one second (FEV₁) is declining with age as displayed in the Fletcher-Peto curve. Despite established benefits of bronchoscopic lung volume reduction (BLVR) using endobronchial valves (EBVs), long-term data suggest a gradual reduction in the magnitude of these benefits.PurposeThis study aimed to compare the rate of lung function change in emphysema patients undergoing BLVR versus those receiving conservative management, utilizing coarsened exact matching to ensure balanced baseline characteristics.Patients and MethodsIn this retrospective single center study data between 2015 and 2021 was analyzed. BLVR patients achieving significant volume reduction (≥563 mL) were matched to conservatively managed controls based on age, sex, BMI, and smoking history. Pulmonary function changes after successful BLVR with valves, including forced expiratory volume in one second (FEV₁) and residual volume (RV), were monitored and analyzed over a 3-year period.ResultsA total of 60 patients, evenly distributed between the two groups (30 each), were included in the analysis. Median FEV₁ change was -0.063 L/year for BLVR patients and -0.066 L/year for controls. No statistically significant differences in annual FEV₁ and RV changes were observed (-0.07 vs -0.08, <i>p</i> = 0.492; -0.07 vs -0.07, <i>p</i> = 0.569; -0.05 vs -0.04, <i>p</i> = 0.636 at follow-ups in years 1, 2, and 3, respectively for FEV₁ and +0.20 vs +0.25, <i>p</i> = 0.643; +0.80 vs +0.65, <i>p</i> = 0.960; +1.0 vs +0.85, <i>p</i> = 0.963 at follow-ups in years 1, 2, and 3, respectively for RV).ConclusionIn this matched cohort analysis, no significant differences in annual changes in FEV₁ or RV progression were observed between patients after successful BLVR with valves and patients under conservative treatment. The results indicate that COPD progression is the main factor for the decline in functional improvement after successful BLVR with valves.