Aspirin May Help to Prevent Asthma

[January 17, 2007] Can an aspirin a day keep asthma away?

Maybe, suggests new research published in the American Journal of Respiratory and Critical Care Medicine. The new study found that adult-onset asthma risk was reduced by 22 percent in men who were already taking a daily aspirin for heart-disease prevention.

"Our findings suggest that low-dose aspirin may have beneficial effects on asthma," says study co-author Dr. Tobias Kurth, an assistant professor of medicine and an associate epidemiologist in the division of aging at Brigham and Women's Hospital in Boston.

But, Dr. Kurth adds, it is too soon to recommend that anyone start using daily aspirin solely for asthma prevention.

Asthma Becoming More Prevalent

As many as 20 million Americans have asthma, according to the American Academy of Allergy, Asthma, and Immunology (AAAAI). Despite advances in treatment, about 5,000 people die due to asthma every year in the United States, the AAAAI reports.

The incidence of asthma has been rising in recent years, according to background information in the study. And that rise coincides with the decreased use of aspirin as people have switched to other over-the-counter pain relievers, or avoided aspirin use in children due to concerns about Reyes syndrome.

That fact led some researchers to wonder if the reduction in aspirin use was contributing to the rise of asthma.

To test that hypothesis, Dr. Kurth and his colleagues reviewed data from the Physicians' Health Study, which began in 1982. They included data from 22,071 male physicians between the ages of 40 and 84.

The physicians were randomly assigned to receive either a daily dose of 325 milligrams of aspirin or a placebo. The original aim of the research was to study aspirin's role in heart-disease prevention.

During the five-year study period, 113 new cases of asthma were diagnosed in the 11,037-member aspirin group, compared with 145 in the placebo group. This represented a 22 percent decrease in the risk of developing asthma for those taking low-dose aspirin, when controlling for other factors that may have contributed to this difference.

Aspirin's Protective Function Unclear

Dr. Kurth says the researchers were unable to study the reasons why aspirin might have this preventive effect against asthma, but theorizes that aspirin's anti-inflammatory effects might play a role.

He cautions, however, that for some people who already have asthma, aspirin can be an irritant that can actually trigger asthma symptoms.

"This is a complex issue and is more of a study for the research community," says Dr. Kurth. The question for researchers now, he says, is "for those at risk of getting asthma, should they be treated with aspirin or not?"

Dr. Rick Vinuya, an allergist and immunologist at Providence Hospital and Medical Center in Southfield, Mich., echoes Dr. Kurth's comments.

"Any time you have an intervention to prevent the onset of disease, it's exciting, and a 22 percent reduction in risk is huge, says Dr. Vinuya.

"But, that excitement is tempered because this is not a cause-and-effect study, but an epidemiological one. This study needs to be followed up with a study specifically designed to answer whether aspirin really does have an affect and how does it work?" Dr. Vinuya continues.

Right now, Dr. Vinuya says, no one should start taking aspirin to prevent asthma.

"This study adds on to the beneficial effects of aspirin. It's a healthy practice to take aspirin to prevent heart attacks and now it looks as if a secondary benefit is a possible decrease in the development of asthma. But, asthma prevention can't be the primary reason for taking daily aspirin," he says.

Always consult your physician for more information.