Efficacy of domiciliary noninvasive ventilation on clinical outcomes in posthospital chronic obstructive pulmonary disease patients: a meta-analysis of randomized controlled trials

Background As newly emerging evidence was given, we conducted a meta-analysis of randomized controlled trials (RCTs) with the following objectives: (I) to evaluate the effect of long-term noninvasive ventilation (NIV) on posthospital chronic obstructive pulmonary disease (COPD) patients with respiratory failure in mortality, blood gas, exacerbation frequency; (II) to distinguish different follow-up length of longterm NIV and its effect on these outcomes. Methods We tried to conduct and report this meta-analysis in accordance with the Cochrane Handbook (version 5.1.0) by searching the PubMed, Embase, Cochrane Library, and Chinese Biomedical Literature for RCTs in humans through April 2020. Studies comparing treatment effects of domiciliary NIV with control therapy in posthospital COPD patients were conducted, and at least one of the following parameters were reviewed: mortality, gas exchange, and exacerbation frequency. Results Five studies with 419 subjects were identified. The exacerbation frequency significantly decreased in patients who received domiciliary NIV [weighted mean difference (WMD) -1.74, 95% CI: -2.90 to -0.57, P=0.004]. No significant difference was found in mortality, partial pressure of arterial oxygen (PaO2), PaCO2, and pH. Subgroup analysis of PaCO2 showed that domiciliary NIV of 3 months was most likely to decrease PaCO2, but not significant (WMD -2.95, 95% CI: -6.11 to 0.21, P=0.07). Conclusions The results indicate that domiciliary NIV decreases the exacerbation frequency of posthospital COPD patients, but may not improve mortality or gas exchange. Further studies are needed to evaluate the benefit of domiciliary NIV on COPD patients.