Study: Cholesterol Drugs May Worsen Asthma
Experts Say the Findings Contradict Some Earlier Studies on the Effects of Statin Drugs
Comparing Studies continued...
Larger studies on the effects of statins in asthma have been contradictory, however, with some showing that statins offer modest benefits to breathing while others have found no net benefit or harm from the medications.
"There are many studies showing the opposite of what I'm saying," says researcher Safa M. Nsouli, MD, an allergist who is director of the Danville Asthma and Allergy Clinic, in Danville, Calif.
Nsouli says he became interested in the question after he noticed that many of his asthma patients who started statin therapy saw their breathing problems escalate.
He says that statins may aggravate asthma because they create an imbalance in immune system cells called helper T cells. Helper T cells fight infection by cranking out chemicals that activate and direct other immune cells to go after invaders.
Statins work, in part, by lowering levels of one kind of helper T cell. To compensate, Nsouli says, the body makes more of a second kind of helper T cell. Those cells are particularly bad for people with asthma triggered by allergy (allergic asthma) because they increase inflammation in the airways.
Advice to People With Asthma
Nsouli acknowledges that his study is small and says it's not a reason for anyone to stop taking a prescribed statin.
"The goal of my study is to make aware the patients who have allergies and asthma to know that being on statins, this might imbalance their immune system and might ... adversely affect their asthma," he tells WebMD. "Therefore they have to be medicated more carefully and more aggressively by their allergy and asthma specialist, rather than forgoing statins."
Other experts agree that the findings are interesting and could be important if they are confirmed in larger studies.
Statins are among the most widely prescribed medications in the U.S. -- taken by an estimated one in four Americans over age 45. Government reports show that about one in 12 adults has asthma.
"The size of the study is quite small," says David Beuther, MD, a pulmonologist and assistant professor of medicine at National Jewish Health in Denver.
"I think it's a signal we need pay attention to make sure that we look into this in more detail and confirm it in other studies before we get too excited about it," Beuther tells WebMD. "But it's probably worth pursuing."
These findings were presented at a medical conference. They should be considered preliminary as they have not yet undergone the "peer review" process, in which outside experts scrutinize the data prior to publication in a medical journal.