COPD patients with chronic hypercapnic respiratory failure receiving domiciliary noninvasive positive pressure ventilation - Analysis of prognostic factors and suggestion for supportive system

Background : Recently, the indication of noninvasive positive pressure ventilation (NPPV) in COPD spreads in not only acute exacerbation but also chronic phase. Although some already have reported the prognosis of patients with COPD receiving domiciliary NPPV, little evidence shows the prognostic factors of those patients. Method : Retrospective analysis in single institution. Result : Twenty-eight cases (20 males) with chronic hypercapnic respiratory failure due to COPD were prescribed domiciliary NPPV during 11 years. At the initiation of NPPV, the age was 74.4±6.7 years-old (mean±standard deviation) and PaCO ₂ was 59.8±10.1 Torr. The 1-year and 5-year survival rates were 85.3% and 26.2%, respectively. Multivariate analysis identified only BMI (body mass index) (hazzard ratio : 0.582, 95% confidence interval : 0.380 to 0.890, p=0.012) as a predictor of survival. Domiciliary NPPV significantly decreased hospitalization times due to exacerbation during one year after initiation in comparison with before initiation (1.54±0.64 and 1.11±1.20 times, respectively, p=0.038). Conclusion : Low BMI was revealed a significant prognostic factor in COPD patients receiving domiciliary NPPV, so it is important to provide the comprehensive supports aimed to restore the general status for improving their survival.