You wouldn't think there'd be a link between the stomach and asthma, yet even as far back as the 1970s asthma experts noticed a connection between asthma and gastrointestinal reflux (GERD).
What is GERD?
GERD is a condition where acid from the stomach works its way back up the esophagus. If this condition is left untreated long term, it can eventually lead to esophageal ulcers, esophageal cancer and even lung damage that can cause asthma.
According to the American Academy of Allergy, Asthma and Immunology (AAAAI.org), a sphincter at the bottom of your esophagus remains closed while food is being digested to prevent backwash. "However, sometimes it relaxes on the job, allowing stomach acid to flow back, or reflux, into the esophagus."
Studies, the AAAAI notes, show that as many as 70 percent of asthmatics have GERD, the same percentage of asthmatics estimated to have allergies. This is a significant percentage, especially when you consider only 20 to 30 percent of people who do not have asthma have GERD.
What is the Connection?
It almost seems asthma and GERD have a synergistic relationship, where some asthma medicines may worsen GERD, and GERD may worsen asthma. GERD has been proven to be an asthma trigger, yet recent studies show it may even cause asthma in some patients.
Actually, back in 2008, researchers at Duke University looked into this relationship. While studying mice, they discovered that "inhaling tiny amounts of stomach fluid... produces changes in the immune system that can drive the development of asthma."
If your asthma gets worse after meals, at night, or when lying down GERD may be considered as the likely cause.
Age and GERD
There are some children with GERD. In fact, when I was a patient of National Jewish back in 1985 my room mate had to sleep with the top half of his bed on stilts to prevent stomach backwash.
Usually, however, GERD is associated with adult onset asthma. If a 40-year-old, for example, all-of-a-sudden develops asthma symptoms, GERD is often considered to be the culprit.
The most common symptom of GERD is heartburn, although it may also cause a sour taste in your mouth, chest pain, chronic cough, trouble breathing at night, sore throat, recurring pneumonia, chronic sinusitis, cavities, inflammed gums, bad breath, or no symptoms at all.
Too often symptoms aren't noticed, and GERD goes uncontrolled. AAAAI notes that in some cases this may lead to uncontrolled asthma.
Testing for GERD
The initial test is usually a barium swallow, where you drink a chalky liquid and radiology equipment allows fluid in your esophagus to show up as gray or black on a screen. I actually did this test as a kid and failed. So my doctor had me do the more invasive pH probe.
The pH probe is where a tube is inserted into your nose down to your stomach, and, while you're sleeping, a printout shows if acid enters your esophagus. I actually passed this test, and GERD was ruled out back then.
