GERD, Asthma Connection Vague: Research Continues

Gatroesophageal Reflux disease (GERD) is reportedly seen in more than 75% of all asthma patients. The obvious correlation leaves researchers searching for answers Does GERD cause asthma? Or does stomach acid simply aggravate preexisting asthma?

In a study published by Johns Hopkins University, researchers examined 16,632 patients from two South Birmingham, England primary healthcare centers. Of this group, 2,269 of the patients were asthmatic. The other 14,363 non-asthmatics were used as a control group.

Within those diagnosed with asthma, 1,297 also suffer from dyspepsia. The study group was also divided by age, sex, and whether the patient had been prescribed an inhaled short acting ß2-agonist in the previous 6 months.

After examination, researchers found patients who had been prescribed these inhalants were twice as likely as both the control group and the untreated asthmatics to have coexistent dyspepsia. They also noted that within the group of untreated asthmatics, the rate of dyspepsia was consistent with the non-asthmatic control group. The trends were consistent in both male and female groups.

The researchers concluded that dyspepsia was significantly association with asthma, specifically in patients who had been inhaled short acting ß2 -agonists. This prevalence was found in 19.1% of the asthmatic patients, vs. 10.7% of patient in the non-asthmatic control population.¹

Officials at the Asthma and Allergy Foundation of America, working with Susan M. Harding, MD, associate professor in the Division of Pulmonary, Allergy, and Critical Medicine and the University of Alabama at Birmingham, report three conclusions after researching the GERD/asthma connection.

* The base of the esophagus and the bronchial tree have a common nerve ending source. When the area is aggravated, both the esophagus and the bronchial tree react. If GERD flares up, asthma flares up also and vice versa.

* Patients experience chest tightening when there is acid in the esophagus.

Microaspiration of acid can occur during a GERD episode, causing decreased lung function.

* Although Harding notes there are multiple triggers for asthma attacks, there is evidence that GERD can cause a significant problem for those asthmatics with the digestive disease. For those who think GERD may be causing respiratory problems, they should determine whether the reflux symptoms appeared before their asthma, whether their breathing becomes more difficult after meals, when lying down, or after exercise, and if their asthma is worse at night. These could all be signs of GERD induced asthma.²

Harding, who is the medical director of the UAB's Sleep-Wake Disorders Center, says she doesn't know if asthma is becoming more common because of GERD, but the digestive disorder is becoming more prevalent.

"Certainly we see GERD being diagnosed more often because of improved public awareness. It may be that patients and physicians are just better at recognizing it. Any way you look at it, GERD is more common now," she said.

Some diagnostic tools for GERD include: barium swallows, 24-hour pH monitoring, or with an endoscopic broncoscopy procedure. Treatments include antacids, alginic acid compounds, H2 blockers, cisapride, and omerprazole. Endoscopy team members can also surgically repair the lower esophageal sphincter to prevent digestive acid from escaping the stomach.³

Philip Katz, MD, suggests a proton-pump inhibitor for one month may help relieve symptoms. He also writes that this could decrease symptoms of asthma.⁴

Harding, however, is quick to note that GERD is not a common problem. Although there are many commercials for new prescriptions on the market to treat this disease, she notes that patients need to consult their physicians before assuming their digestive problems are linked to acid reflux.

"In some asthmatics who do not have reflux symptoms, when you control their GERD, you control their asthma. One of our recent studies has shown that about 60% of asthmatics have GERD but do not have reflux symptoms," she said.

While most GERD patients are adult, Nanette Bacani-Tan, BSN, RN-C, CGRN, has written a report about the digestive disease in relation to childhood asthma. She notes that more than one-fourth of all children are diagnosed with GERD, but only when the acid is excessive and causes complications does the condition become pathologic. Pathologic reflux decreases clearance, impairing mucosal resistance and disturbing the upper esophageal sphincter.

Her clinical presentations report these symptoms often persist in children for 1 to 2 years and can cause malnutrition due to regurgitation. The acid can also cause apnea, hoarseness, esophagitis, Barrett's esophagus, and respiratory problems. GERD can also cause the neurological disorder Sandifer's syndrome in some children as well.

"Respiratory problems do not have to be presumed to be asthma. They could be from chronic GERD," she said. "[Doctors should ask] could these respiratory problems be GERD and not necessarily asthma in origin?"

Researchers are looking for that answer and many others concerning these two conditions, including whether a silent form of GERD can also exacerbate asthma.

For the latest information on GERD and other digestive disorders, log onto www.endonurse.com.

References:

1. Beech T, Huntley B, Knight W, Powell N. 25 Increased Prevalence of Dyspepsia in Asthma. www.hopkins-allergy.org. July 26, 2001.

2. Gastroesophageal Reflux Disease (GERD) and Asthma. Asthma.about.com. July 26, 2001.

3. GERD and Asthma: What's the Connection? www.aafa.org July 26, 2001.

4. Katz P, MD. GERD & Asthma. www.ivillagehealth.com. July 26, 2001.