Survival and characteristics of hospitalized patients with COPD who needed non-invasive mechanical ventilation during an exacerbation

Introduction: In COPD patients, treating exacerbations associated with severe hypercapnic respiratory failure with non-invasive mechanical ventilation (NIMV) is effective.However, evidence on the prognosis of these patients is scarce. We aimed to determine the clinical characteristics and long-term survival of COPD patients who had been hospitalized due to an acute exacerbation of COPD that required NIMV. Material and methods: A retrospective study was conducted with COPD patients from the monographic clinic at Hospital Universitario La Princesa in Madrid, Spain. They were split into two groups, whether they required NIMV during some COPD exacerbation, or not. Different clinical variables were analysed:deaths, age, lung function (FEV1), BODE and BODEx indices, number of acummulative admissions, MRC grade 4 dyspnea, presence of comorbidities as well as accumulated survival up to seven years of follow-up by means of Kaplan-Maier curves. Results: Overall, 409 patients were studied, 72.1% were male, with a mean±SD age of 72,2±10 years.11.5% of patients needed NIMV during the exacerbations, 75% of whom were male. 23.4% of patients treated with NIMV died and so did 8.8% of those who did not need this treatment (p= 0.005).After comparing the clinical variables of both group (Table 1), significant differences were found for the distribution of FEV1, BODE, BODEx, number of admissions and dyspnea. Long term survival was similar between groups(p=0,058 by Kaplan-Meier). Conclusions: Patients treated with NIMV present a more severe COPD, requiring more hospitalizations and a trend of increased mortality.