TNF-alpha may be important in the pathogenesis of COPD. Consequently, the use of TNF-alpha antagonists has been advocated for its treatment.
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.
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).
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.