[Effect of home noninvasive positive pressure ventilation on patients with severe stable chronic obstructive pulmonary disease: a meta-analysis].

Objective: To evaluate the effect of home noninvasive positive pressure ventilation (NPPV) on patients with severe stable chronic obstructive pulmonary disease(COPD) by meta-analysis. Methods: The data of this meta-analysis was retrieved from the PubMed, EMBASE, Cochrane library, Wanfang, Weipu and CNKI databases from January 1980 to January 2016. Randomized controlled trials (RCTs) on comparison of the effect of home NPPV in patients with severe stable COPD were enrolled. The enrolled data were divided into different subgroups in terms of the levels of inspiratory positive airway pressure(IPAP), different duration of ventilation per day, and different levels of baseline hypercapnia on change in PaCO(2). Meta-analysis was performed to compare the effect of different subgroups by RevMan 5.3. Results: Ten studies with a total of 789 patients were included. Home NPPV improved 6-minute walk distance (WMD: -45.12, 95% CI: -85.39--4.85, P =0.03) and forced expiratory volume in the first second [standard mean difference(SMD): -0.26, 95% CI: -0.51--0.02, P =0.03]after 1 year of ventilation, but did not improve the mortality, PaCO(2,)PaO(2,)pH, FVC, maximal inspiratory pressure (MIP), FEV(1)/FVC, maximal voluntary ventilation(MVV) total sleep time, sleep efficiency and the proportion of rapid eye movement (REM) sleep. Subgroup analysis showed that home NPPV can significantly reduce the PaCO(2) in patients ventilated with 18 cmH(2)O(1 cmH(2)O=0.098 kPa) and higher IPAP levels than those with lower IPAP levels (SMD: -0.6, 95% CI : -1.09--0.12, P =0.01), and in patients with NPPV for at least 5 h per day and those with lower duration (SMD: -0.45, 95% CI : -0.87--0.02, P =0.04), and in patients with baseline PaCO(2) of at least 55 mmHg (1 mmHg=0.133 kPa) (SMD: -0.69, 95% CI : -1.07--0.31, P =0.00) than those with lower levels. Conclusions: Home NPPV can improve 6MWD and FEV(1) in severe stable COPD patients but does not improve the mortality, gas exchange and sleep efficiency. Patients may gain more benefits when using higher IPAP levels, longer ventilation per day and in those with higher baseline PaCO(2).