title: Outcomes associated with invasive and noninvasive ventilation among patients hospitalized with exacerbations of chronic obstructive pulmonary disease.
abstract: OBJECTIVE
  Small clinical trials have shown that noninvasive ventilation (NIV) is efficacious in reducing the need for intubation and improving short-term survival among patients with severe exacerbations of chronic obstructive pulmonary disease (COPD). Little is known, however, about the effectiveness of NIV in routine clinical practice.
  
  
  OBJECTIVE
  To compare the outcomes of patients with COPD treated with NIV to those treated with invasive mechanical ventilation (IMV).
  
  
  METHODS
  This was a retrospective cohort study of 25 628 patients hospitalized for exacerbation of COPD who received mechanical ventilation on the first or second hospital day at 420 US hospitals participating in the Premier Inpatient Database.
  
  
  METHODS
  Initial ventilation strategy.
  
  
  METHODS
  In-hospital mortality, hospital-acquired pneumonia, hospital length of stay and cost, and 30-day readmission.
  
  
  RESULTS
  In the study population, a total of 17 978 (70%) were initially treated with NIV on hospital day 1 or 2. When compared with those initially treated with IMV, NIV-treated patients were older, had less comorbidity, and were less likely to have concomitant pneumonia present on admission. In a propensity-adjusted analysis, NIV was associated with lower risk of mortality than IMV (odds ratio [OR] 0.54; [95% CI, 0.48-0.61]). Treatment with NIV was associated with lower risk of hospital-acquired pneumonia (OR, 0.53 [95% CI, 0.44-0.64]), lower costs (ratio, 0.68 [95% CI, 0.67-0.69]), and a shorter length of stay (ratio, 0.81 [95% CI, 0.79-0.82]), but no difference in 30-day all-cause readmission (OR, 1.04 [95% CI, 0.94-1.15]) or COPD-specific readmission (OR, 1.05 [95% CI, 0.91-1.22]). Propensity matching attenuated these associations. The benefits of NIV were similar in a sample restricted to patients younger than 85 years and were attenuated among patients with higher levels of comorbidity and concomitant pneumonia. Using the hospital as an instrumental variable, the strength of association between NIV and mortality was modestly attenuated (OR, 0.66 [95% CI, 0.47-0.91]). In sensitivity analyses, the benefit of NIV was robust in the face of a strong hypothetical unmeasured confounder.
  
  
  CONCLUSIONS
  In a large retrospective cohort study, patients with COPD treated with NIV at the time of hospitalization had lower inpatient mortality, shorter length of stay, and lower costs compared with those treated with IMV.
authors.affiliation: Center for Quality of Care Research, Baystate Medical Center, Springfield, Massachusetts2Division of General Internal Medicine, Baystate Medical Center, Springfield, Massachusetts3Tufts Clinical and Translational Science Institute, Tufts University School.
authors.forename: Peter K
authors.initials: PK
authors.lastname: Lindenauer
authors.affiliation: Center for Quality of Care Research, Baystate Medical Center, Springfield, Massachusetts2Division of General Internal Medicine, Baystate Medical Center, Springfield, Massachusetts3Tufts Clinical and Translational Science Institute, Tufts University School.
authors.forename: Mihaela S
authors.initials: MS
authors.lastname: Stefan
authors.affiliation: Center for Quality of Care Research, Baystate Medical Center, Springfield, Massachusetts.
authors.forename: Meng-Shiou
authors.initials: MS
authors.lastname: Shieh
authors.affiliation: Center for Quality of Care Research, Baystate Medical Center, Springfield, Massachusetts4University of Massachusetts Amherst School of Public Health and Health Sciences, Amherst.
authors.forename: Penelope S
authors.initials: PS
authors.lastname: Pekow
authors.affiliation: Department of Medicine, Medicine Institute, Cleveland Clinic, Cleveland, Ohio.
authors.forename: Michael B
authors.initials: MB
authors.lastname: Rothberg
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Tufts University School of Medicine, Boston, Massachusetts.
authors.forename: Nicholas S
authors.initials: NS
authors.lastname: Hill
mesh_terms: D000208:Acute Disease; D000368:Aged; D015897:Comorbidity; D003428:Cross Infection / Q000453:epidemiology; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D007297:Inpatients; D007902:Length of Stay / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D063087:Noninvasive Ventilation / Q000009:adverse effects* / Q000401:mortality; D016017:Odds Ratio; D010359:Patient Readmission / Q000706:statistics & numerical data; D011014:Pneumonia / Q000453:epidemiology; D029424:Pulmonary Disease, Chronic Obstructive / Q000628:therapy*; D012121:Respiration, Artificial / Q000009:adverse effects* / Q000379:methods* / Q000401:mortality; D012189:Retrospective Studies; D016896:Treatment Outcome; D014481:United States / Q000453:epidemiology