A commonly used treatment for acid reflux does not improve asthma symptoms or control in patients who do not have symptoms of gastroesophageal reflux (GER), according to a new study supported by the National Heart, Lung, and Blood Institute (NHLBI) of the National Institutes of Health and by the American Lung Association (ALA). This suggests that silent GER (acid reflux that causes only minimal or no reflux symptoms) does not play a role in asthma, as has previously been thought.

The multi-center, randomized clinical trial is the first to evaluate whether adding esomeprazole (Nexium), to asthma therapy might improve asthma control and quality of life in asthma patients who could have silent GER. Esomeprazole is a type of medication called a proton pump inhibitor (PPI), which is used to treat heartburn, GER, and ulcers by reducing stomach acid. Researchers found no differences between patients treated with the reflux medication and those who were not. The results are published in the April 9, 2009, issue of the New England Journal of Medicine.

"This study helps us rule out silent GER as one possible contributor to poorly controlled asthma, and is important news for many patients," said NHLBI director Elizabeth G Nabel. "Asthma patients who take medication for acid reflux but who do not have reflux symptoms should talk with their doctors about whether they should continue the medication."

Participants were randomly selected to either use esomeprazole (40 milligrams) twice daily or a similar looking placebo (inactive ingredient) for six months while continuing to take their asthma medications. They tracked their symptoms and asthma control through asthma diaries, and visited the research clinic monthly for lung function testing. They also completed standard quality-of-life questionnaires.

Overall, the numbers and severity of asthma symptoms, and quality-of-life scores were similar between participants taking esomeprazole and participants who did not take the anti-reflux medication. In addition, the outcomes were similar among subgroups of participants, such as those with silent GER, those who were overweight or obese, and those who had frequent night awakenings due to asthma.

"This study demonstrates that silent GER does not play a role in worsening asthma symptoms and control," said Robert A Wise, a co-author of the paper and a professor at Johns Hopkins University School of Medicine, where he is also director of the coordinating center for the ALA Asthma Clinical Research Centers. "Based on these results, we also believe that doctors do not need to test for GER in asthma patients unless the patient is reporting symptoms of acid reflux."

Asthma patients with GER symptoms, however, may find relief from acid reflux with esomeprazole or other PPIs.

"This study fills a gap in our knowledge about the use of anti-reflux therapy in patients with poorly controlled asthma and it will help inform the next update of the asthma clinical guidelines," noted Virginia Taggart, programme director in the NHLBI Division of Lung Diseases, and the study's project officer.