Bacterial Infection Makes COPD Worse

COPD patients with Pseudomonas aerguinosa infection have worse clinical outcomes

/ Author:  / Reviewed by: Robert Carlson, M.D

(RxWiki News) Many diseases are caused by or related to infections. Likewise, infections can worsen almost any disease, including chronic obstructive pulmonary disease (COPD) - one of the most common lung diseases.

COPD patients who get infected with a bacterium called Pseudomonas aeruginosa (P. aeruginosa) may have worse outcomes and be hospitalized more than COPD patients who are not infected.

"Get treated early for infections if you have COPD."

Past research has shown that people with more severe cases of COPD are more likely to get infected with P. aeruginosa. For their current study, Sanjay Sethi, MD, FACP, of the University at Buffalo, SUNY, and colleagues wanted to see how the infection might affect patient outcomes.

Bacterial infections can play a huge role in COPD. They can cause inflammation and exacerbations, or fits, of symptoms. Bacterial infections also are linked to a higher risk of death among people with COPD.

"In this study, we wanted to determine if infection with P. aeruginosa was associated with poorer clinical outcomes, such as hospitalizations, need for intensive care, and greater numbers of exacerbations," says Dr. Sethi.

The researchers studied 177 COPD patients with and without P. aeruginosa infection. They compared hospitalizations, admissions to the intensive care unit, and COPD exacerbations between the two groups.

They found that COPD patients with P. aeruginosa infection had much higher rates of hospitalization than those who were not infected. Infected patients were also more likely to be admitted to an intensive care unit or have an exacerbation.

"As COPD progresses, hospitalizations and exacerbations tend to increase and we had to account for that in our analysis," explains Dr. Sethi.

With this in mind, the researchers matched infected patients to non-infected patients who had COPD for a similar amount of time. Using this method, they could link patient outcomes to the bacteria rather than the amount of time patients had COPD.

Dr. Sethi says that similar studies are being done on other bacteria found in COPD patients to see if these outcomes are unique to P. aeruginosa or if they can be the result of these other bacteria.

"The possibility exists that, in our study, P. aeruginosa may be simply a 'colonizing bacteria' - a marker for worsening COPD - rather than a cause of the worse clinical outcomes," Dr. Sethi notes. "However, we and others have shown that P. aeruginosa behaves as an infectious pathogen in COPD."

That is, the bacterium appears to play an active role in worsening COPD.

He adds that similar infections play a major role in the development of related airway diseases like cystic fibrosis.

"This study suggests that we should pay more attention to this bacteria in COPD, and treatments to deal with this pathogen in COPD should be developed," Dr. Sethi concludes.

These findings were presented at the 2012 International Conference of the American Thoracic Society (ATS). As such, the study has yet to be evaluated by a peer-reviewed scientific journal.

Funding for the study came from the VA Merit Review.

Reviewed by: 
Review Date: 
May 22, 2012
Last Updated:
August 3, 2012