Aspirin Appears Protective in COPD Patients
by Ed Susman, Contributing Writer, MedPage Today
SAN DIEGO – Patients diagnosed with chronic obstructive pulmonary disease (COPD) who are also on aspirin therapy appear to have a lower rate of COPD exacerbations, researchers reported at the annual conference of the American Thoracic Society.
The risk of experiencing any acute exacerbation of COPD was reduced by 18% among patients on aspirin when compared with those not on aspirin therapy (IRR 0.82, 95% CI 0.68-0.98), reported Ashraf Fawzy, MD, of Johns Hopkins University in Baltimore.
In his poster discussion presentation, Fawzy said that the finding was driven by the apparent ability of aspirin therapy to prevent moderate acute exacerbation – but the treatment did not seem to have any significant impact on more severe exacerbations.
The mean exacerbation rate for any event was 0.51 per person-year in the 495 patients on aspirin and 0.63 per person-year in the 495 matched patients who were not on aspirin therapy (P=0.03), he reported. The moderate exacerbations occurred at a mean rate of 0.32 per person-year in the aspirin users and 0.43 per person-year in the non-aspirin patients (P=0.006). However among those patients with a severe exacerbation, the rate was 0.19 per person-year in the aspirin group and 0.20 in the non-aspirin group (P=0.8).
"We probably are not at the point of using these findings to recommend giving aspirin to people with COPD," Fawzy cautioned. "This really is just an observational study. It might be difficult to do a randomized controlled clinical trial in this group of patients, but perhaps a more robust observational study could add to the weight of these findings. Personally I would like to have my COPD patients on aspirin. It is relatively low risk and has been shown to have multiple other benefits, and especially in patients with COPD, who are known to have higher cardiovascular co-morbidity and morbidity."
The mechanism of action may be due to aspirin's ability to reduce inflammation, he suggested. Aspirin inhibits platelet activity and has anti-inflammatory properties and has been associated with reduced all-cause mortality among patients with COPD, but there has been a paucity of information regarding aspirin use and its impact or association with COPD-related exacerbation.
The retrospective, propensity matching study did not have information about the dose or duration of aspirin therapy, and the only medication the research team was able to control for was whether patients were using inhaled corticosteroids.
Fawzy also noted that overall the exacerbation rate for the entire cohort was low. Half the patients in the study did not report any exacerbation of COPD in the 2.5 to 3 years of the study period.
Asked for his perspective, Steven Lommatzsch, MD, of the National Jewish Hospital/University of Colorado in Denver, who was not involved with the study, told MedPage Today: "A lot of COPD patients will [already] be on aspirin because many are at risk of heart disease. Heart disease is still the number 1 killer in this country.
"This would be a low-risk treatment, except possibly in patients who might have a bleeding risk. However, it might be that this benefit in preventing COPD exacerbations might trump the bleeding risk. Unless these patients had a known ulcer or something like that, I think they probably should be on aspirin therapy."
For the study, Fawzy et al assessed the SPIROMICS (Subpopulations and Intermediate Outcome Measures in COPD Study) multicenter observational cohort, specifically looking at patients who self-reported daily aspirin use. The team then used propensity scoring to develop a 1:1 match of aspirin users and non-users.
The patients in the study were about 67 years old, about 40% were women, 12% were black, 38% had less than a high school education, about 28% were current smokers, and 24% were currently on home oxygen supplementation. In addition, 55% of the patients had been diagnosed with hypertension, 7% with coronary arterial disease, 3% with congestive heart failure, and 15% with diabetes; 5% had a history of stroke, 43% were on statin therapy, 17% were on beta blockers, 46% had used inhaled corticosteroids within the past 3 months, and 32% were categorized as obese.
Fawzy reported having no relevant relationships with industry.
Lommatzsch reported having a relationship with AstraZeneca.
Source: Society meeting abstract