November 14, 2011 (Boston, Massachusetts) — Statins are among the most widely prescribed drugs in the world and help to stave off cardiovascular disease, but results from a small study suggest that they might worsen asthma control, researchers said here at the American College of Allergy, Asthma & Immunology 2011 Annual Scientific Meeting.

Statin drugs, which are 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors, are effective at lowering cholesterol, but they also influence allergic inflammation with immunomodulatory activities, said lead author Safa Nsouli, MD, director of the Danville Asthma and Allergy Clinic in California.

These include the downregulation of the T helper (TH)1 phenotype response and the upregulation of the TH2 phenotype response.

Dr. Nsouli said he noticed that some of his patients with asthma had exacerbations and worsening control. When he investigated, he observed that they were using statins.

The observation prompted him to conduct this small study. He compared 20 patients with asthma who were taking statins with 20 matched patients who were not taking statins.

"The patients were very carefully selected and did not have any other medical factors that could interfere with asthma exacerbation," Dr. Nsouli told Medscape Medical News.

The patients were seen at 3, 6, and 12 months. At each follow-up visit, measures of the following asthma factors were taken: forced expiratory volume in 1 second (FEV1), the use of beta agonists, nocturnal wakening, and daytime exacerbation symptoms.

The investigators found that at 3 months, patients in the statin group had a 20% decrease in FEV1 from baseline, compared with patients in the nonstatin group, who had a 10% decrease. At 6 months, the decreases were 28% and 12%, respectively; at 12 months, the decreases were 35% and 14%.

The use of beta-agonist rescue inhalers was also higher in the statin group than in the nonstatin group, Dr. Nsouli said. At 12 months, beta-agonist use was up by 72% in the statin group, compared with 9% in the nonstatin group.

At 3 months, peak expiratory flow was decreased by 18% in the statin group, and by 4% in nonstatin group. At 6 months, it was decreased by 25% and 9%, respectively, and at 12 months, it was decreased by 39% and 11%.

Finally, statin users had more nighttime wakening and a greater increase in daytime symptoms than nonusers. At 12 months, the increase in nighttime wakening was 31% and 3%, respectively, and the increase in daytime asthma symptoms was 35% and 3%.

"More studies are needed to demonstrate that statins cause possible immune changes that promote allergic diseases such as asthma," Dr. Nsouli said. "Statins inhibit proinflammatory cytokines, which is good for the cardiovascular system, but they also suppress the major histocompatibility complex, class II, which is detrimental for patients with asthma," he explained.

Physicians who notice that their patients' asthma is worsening should find out if they are taking statins. Dr. Nsouli suggested.

He also said that patients with asthma who are prescribed statins should be informed that, because of the adverse immunomodulatory effects that statins produce, their asthma might get worse.

"This does not mean that patients with asthma who need to take statins should stop taking these drugs. But it does mean that they should be treated more aggressively," Dr. Nsouli said.

Dr. Chitra Dinakar

Chitra Dinakar, MD, from the University of Missouri School of Medicine in Kansas City, told Medscape Medical News that she thinks the observations from this study are interesting, but stressed their preliminary nature.

"He had 20 patients in each group. The dose of statins wasn't clear, neither was the patient profile, but the study is thought provoking," said Dr. Dinakar, who was comoderator of the oral session.

"It tells us that we need to be watching out for patients with asthma who are on statins to see if the statins do indeed affect their control. The data are preliminary at this point, but they do raise doubt. The subject merits further study."

Dr. Nsouli has disclosed no relevant financial relationships. Dr. Dinakar reported financial relationships with AstraZeneca and GlaxoSmithKline.

American College of Allergy, Asthma & Immunology (ACAAI) 2011 Annual Scientific Meeting: Abstract 30. Presented November 6, 2011.


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