Bronchoscopic Lung Volume Reduction Procedures for Emphysema: A Network Meta-Analysis

Abstract

Importance: Bronchoscopic lung volume reduction (BLVR) offers alternative novel treatments for patients with emphysema. Comprehensive evidence for comparing different BLVR remains unclear. Objective: To estimate the effects of different BLVR on patients with emphysema. DataSources: PubMed, EMBASE, Cochrane Library, and Web of Science databases from January 2001 to August 2017were searched. Study Selection: Randomized clinical trials (RCT) evaluated effects of BLVR on patients with emphysema. Data Extraction and Synthesis: The relevant information was extracted from the published reports with a predefined data extraction sheet, and the risk of bias was assessed with the Cochrane risk of bias tools. Main Outcomes and Measures: Pair-wise meta-analyses were made using the random-effects model. A random-effects network meta-analysis was applied within a Bayesian framework. The quality of evidence contributing to each network estimate was assessed using the GRADE framework. Results: 13 trials were deemed eligible, including 1993 participants. The quality of evidence was rated as moderate in most comparisons. Medical care (MC)was associated with the lowest adverse events compared with intra-bronchial valve (IBV)(-2.5,[-4.70 to -0.29]), endobronchial valve (EBV) (-1.73, [-2.37 to -1.09]), lung volume reduction coils (LVRC) (-0.76, [-1.24 to -0.28]), emphysematous lung sealant (ELS) (-1.53, [-2.66 to -0.39]), and airway bypass(-1.57, [-3.74 to 0.61]).Adverse events in LVRC were lower compared with ELS (-0.77,[-2.00 to 0.47]).Bronchoscopic thermal vapor ablation (BTVA) showed significant improvement inFEV1 compared with MC (0.99, [0.37 to 1.62]), IBV (1.25, [0.25 to 2.25]), and LVRC (0.72,[0.03 to 1.40]).6 MWT in ELS was significantly improved compared with other four BLVR, sham control, and MC (-1.96 to 1.99).Interestingly, MC showed less improvement in FEV1 and 6 MWT compared with EBV (-0.45, [-0.69 to -0.20] and -0.39, [-0.71 to -0.07], respectively).The mortality in MC and EBV was lower compared with LVRC alone (-0.38, [-1.16 to 0*41] and -0.50, [-1.68 to 0*68], respectively). BTVA and EBV led to significant changes in SGRQ compared with MC alone (-0.74, [-1.43 to -0.05] and 0.44, [0.11 to 0.78], respectively). Conclusions and Relevance: BLVR offered a clear advantage for patients with emphysema. EBV had noticeable beneficial effects on the improvement of FEV1, 6MWTand SGRQ, and was associated with lower mortality compared with MC in different strategies of BLVR. Funding: This project was supported by National major research program on Natural Science of China (91542164). Competing interests: The authors declare that they have no competing financial interests. Ethics Approval Statement: ??