Working in laboratory experiments with mice, Duke researchers have determined that inhaling tiny amounts of stomach fluid that back up into the esophagus can drive the development of asthma.

Studies have shown that anywhere from 50 to 90 percent of asthma patients experience some aspect of gastroesophageal reflux disease (GERD), a condition in which gastric fluid from the stomach backs up into the esophagus, causing what is commonly known as heartburn.

In the experiments at Duke, researchers observed that mice whose lungs had been inserted with miniscule amounts of gastric fluid developed an asthma-like immune system response more frequently than mice that were exposed to allergens but not the gastric fluid.

"This is the first experimental evidence in a controlled, laboratory setting linking these very two common conditions in humans," said Dr. Shu Lin, an assistant professor of surgery and immunology at Duke and senior author of the study, in a news release.

"This does not mean that everyone with GERD is going to develop asthma, by any means," said Dr. William Parker, assistant professor of surgery at Duke and co-author of the study, in the release. "But it may mean that people with GERD may be more likely to develop asthma."

Lin says patients who already have GERD can minimize gastric reflux - and thereby lessen their chances of developing asthma - by following a few simple guidelines:

*eat smaller meals and eat several hours before going to bed
*raise the head of the bed a few inches; maintain a healthy weight
*limit fatty goods, coffee, tea, caffeine and alcohol

Related Links

1. Watch a video of Dr. William Parker explaining the link between GERD and asthma.