Reflux Can Cause Cough in Asthmatics, but Reverse Is Unlikely
WebMD News Archive
Oct. 17, 2000 -- Reflux, popularly known as 'heartburn,' is much more than a burning sensation in the esophagus. It can cause chest pain, laryngitis, wheezing, or coughing, say experts, and the symptoms may be even more confusing in asthmatics.
The most crucial question is determining which comes first, cough or reflux? The answer is reflux, according to a study of more than 100 asthmatics, which also found that the more coughing episodes an asthmatic patient experiences in 24 hours, the stronger the reflux-cough link. The findings were presented at the 65th annual scientific meeting of the American College of Gastroenterology.
So does that mean that an asthmatic patient who has reflux should get the reflux under control before tackling his or her asthma?
Study author Amnon Sonnenberg, MD, professor of medicine at the University of New Mexico Health Sciences Center in Albuquerque tells WebMD that his study doesn't answer that question. He says, however, "it may be likely that reflux control will eliminate the cough."
Patients with asthma were selected from outpatient treatment clinics at the Veteran Administration Medical Centers in Albuquerque. Sonnenberg and colleagues evaluated the patients using 24-hour monitoring of the acid in the esophagus; reflux is the backward flow of acid into the esophagus. Patients also wore 24-hour electronic monitors to record each cough episode or wheeze episode, he says.
The researchers compared the number of cough and wheeze episodes with the number of reflux episodes. Sonnenberg says they found that almost half of cough and wheeze episodes were associated with reflux. In addition, Benjamin Avidan, MD, a research fellow at University of New Mexico and Sonnenberg's co-author, tells WebMD that "40% of the coughs followed a reflux episode and 6% preceded reflux."
"The conclusion we can offer is that reflux causes cough, but the reverse is not likely: Cough is unlikely to cause reflux," Sonnenberg says.
"These data seem to show that about half of the episodes of coughing were preceded by a reflux episode," says Philip O. Katz, MD, chief of gastroenterology at Graduate Hospital in Philadelphia, Pa. He says, however, that it isn't clear what this means in terms of treatment.
Katz, who was not involved in the study, tells WebMD that many experts are interested in the reflux-cough link and are attempting to evaluate "to what extent is cough a predictor of clinical outcome [of reflux]."
Katz says that cough is one of several irregular reflux symptoms that have become the focus of recent studies. " What we are really saying is that a patient can have reflux without heartburn. Symptoms cans be cough, wheeze, chest pain or laryngitis, for example," he says.
Nonetheless for now, Katz says that in the primary care setting, evaluation of cough should still begin with examining the lungs. Reflux as the cause of cough should only be considered after the lungs have been thoroughly evaluated.