Noninvasive positive pressure ventilation (NPPV) has been proposed in COPD patients with acute on chronic respiratory failure (ACRF) in order to avoid endotracheal intubation and to improve immediate outcome, but long-term outcome of this therapeutic approach is still undefined. We evaluated short- and long-term (1 year) outcome of early administration of NPPV in 24 patients with ACRF due to exacerbated COPD (Group A) in comparison with 24 matched historical-control patients treated conventionally (Group B). Patients of Group A were initially treated with NPPV via nasal mask in the presence of pH < or = 7.32, and/or Pa,O2 < 7.98 kPa, and/or Pa,CO2 > 7.18 kPa, plus signs of respiratory distress. In-hospital survival rate was not significantly different in Group A vs Group B, but the patients treated with NPPV showed an earlier improvement in blood gases and a better pH and respiratory rate at discharge. Only 2 patients of Group A needed endotracheal intubation as compared with 9 of Group B. Hospital stay was significantly reduced in survivors of Group A vs Group B. Further severe relapses of ACRF in Group A were treated using NPPV. The number and length of further hospitalizations for pulmonary exacerbations were significantly higher in Group B compared with Group A. The survival rate at 12 months was significantly lower in Group B than in Group A (50% vs 71%). In conclusion, NPPV administration in patients with ACRF due to exacerbated COPD improves not only immediate but also long-term outcome.