title: TNF-alpha antagonists and the prevention of hospitalisation for chronic obstructive pulmonary disease.
abstract: BACKGROUND
  TNF-alpha may be important in the pathogenesis of COPD. Consequently, the use of TNF-alpha antagonists has been advocated for its treatment.
  
  
  METHODS
  We conducted an observational study to evaluate the effectiveness of TNF-alpha antagonists in preventing COPD hospitalisations in a cohort of patients diagnosed with both RA and COPD identified from a health claims database. A nested case-control approach was used to match each case hospitalised to 10 controls on age and cohort entry date. Data on prescribed medications during the year prior to the index date were obtained. Rate ratios (RR) of COPD hospitalisation were estimated by conditional logistic regression, after adjustment for COPD severity and concomitant RA medication use.
  
  
  RESULTS
  The cohort included 15,771 subjects with both RA and COPD, of which 1205 were hospitalised for COPD during follow-up. The adjusted RR of COPD hospitalisation associated with the use of TNF-alpha antagonists was 0.62 (95% confidence interval (CI) 0.43-0.89). This rate reduction was due to etanercept (RR 0.49, 95% CI 0.29-0.82) but not infliximab (RR 0.95, 95% CI 0.59-1.52).
  
  
  CONCLUSIONS
  Our finding of a halving in the rate of COPD hospitalisation associated with the use of etanercept corroborates the potential importance of TNF-alpha in the pathogenesis of COPD. This study supports the initiation of randomised controlled trials of this TNF-alpha antagonist among COPD patients at high risk of severe exacerbations.
authors.affiliation: Division of Clinical Epidemiology, McGill University Health Centre, Canada. samy.suissa@clinepi.mcgill.ca <samy.suissa@clinepi.mcgill.ca>
authors.forename: Samy
authors.initials: S
authors.lastname: Suissa
authors.forename: Pierre
authors.initials: P
authors.lastname: Ernst
authors.forename: Marie
authors.initials: M
authors.lastname: Hudson
mesh_terms: D000368:Aged; D000911:Antibodies, Monoclonal / Q000627:therapeutic use; D018501:Antirheumatic Agents / Q000627:therapeutic use; D001172:Arthritis, Rheumatoid / Q000150:complications / Q000188:drug therapy*; D016022:Case-Control Studies; D015331:Cohort Studies; D000068800:Etanercept; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data*; D006801:Humans; D007074:Immunoglobulin G / Q000627:therapeutic use; D000069285:Infliximab; D007345:Insurance Claim Review; D008297:Male; D029424:Pulmonary Disease, Chronic Obstructive / Q000150:complications / Q000188:drug therapy*; D018124:Receptors, Tumor Necrosis Factor / Q000627:therapeutic use; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors*
chemical_list: D000911:Antibodies, Monoclonal; D018501:Antirheumatic Agents; D007074:Immunoglobulin G; D018124:Receptors, Tumor Necrosis Factor; D014409:Tumor Necrosis Factor-alpha; D000069285:Infliximab; D000068800:Etanercept