Gastroesophageal reflux occurs when there is regurgitation of food into the esophagus. The predominant symptom of GER is heartburn. Gastroesophageal reflux disease is diagnosed when heartburn is present two or more times a week. The International Foundation for Functional Gastrointestinal Disorders reports that one-third of the United States population has GERD, which is one of the most common reasons for clinic visits. Complications of GERD include ulceration or stricture of the esophagus, as well as Barrett's esophagus, which can be a precursor to esophageal cancer. Severe GER can also result in chronic lung problems.
Function
Moving food from the mouth, into the stomach and forward requires a precise coordination of the muscles and structures within the esophagus, including the lower esophageal sphincter. The lower esophageal sphincter is a muscular ring-like structure situated between the esophagus and stomach that prevents food in the stomach from going backwards into the esophagus. When this sphincter fails to close properly or opens at inappropriate times, stomach contents regurgitate into the esophagus. Stomach contents are acidic and this acidity may injure the esophageal lining and any other tissue it contacts, such as the lungs. In severe GER, refluxed material can be aspirated into the lung tissue, resulting in inflammation and tissue damage.
Types
The National Digestive Diseases Information Clearinghouse reports GERD has been linked to several lung conditions, including chronic cough, asthma and pulmonary fibrosis. The acid reflux irritates the throat as well as the lungs when aspirated. Both the throat and lungs have receptors that stimulate the cough mechanism in an attempt to eliminate the irritant. According to the Cleveland Clinic, approximately 75 percent of patients who have asthma also have GERD. It is unclear exactly what the relationship is between GERD and asthma, however, Littner and colleagues reported in a September 2005 study published in "Chest," that, in patients with both GERD and asthma, treatment with an anti-GERD medication improved asthma symptoms. In long-standing GERD, prolonged acid exposure is thought to be the etiology of pulmonary fibrosis, scarring of the lung tissue, resulting in severe loss of lung function, shortness of breath and diminished exercise capability.
Features
Clinical features that suggest lung involvement in patients with GER or GERD include heartburn associated with chronic cough, wheezing, shortness of breath and insomnia. These symptoms are suggestive of asthma, or reactive airways disease, in response to acid exposure. Symptoms of pulmonary fibrosis also include wheezing and shortness of breath but often progressive weight loss and anorexia is present as the work of breathing overwhelms other metabolic functions.
Identification
Diagnosis of GERD-related lung problems begins with a clinical suspicion. The presence of a chronic cough or asthma in a patient with known GERD raises the possibility of acid reflux as the culprit. Asthma that does not respond to usual asthma medications, being later in life, as well as asthma that gets worse with eating, exercise or lying down, suggests acid reflux-induced lung disease. The diagnosis is further established with acid monitoring of the esophagus and pulmonary function tests to confirm the presence of both acid reflux and lung disease. Improvement of asthma symptoms with the use of a medication for GERD, such as a proton pump inhibitor, helps establish the diagnosis.
Treatment
It is important for GERD-related asthmatic patients to be compliant with prescribed asthma medications, according to the Cleveland Clinic. Measures to control GERD also help with lung symptoms, including elevating the head of the bed, eating small and frequent meals, not smoking, maintaining a normal weight, and using medications including antacids, H2 blockers and proton pump inhibitors. Rarely, surgery may be required to eliminate acid reflux.
References
- National Digestive Diseases Information Clearinghouse: Heartburn, Gastroesophageal Reflux (GER), and Gastroesophageal Reflux Disease (GERD)
- International Foundation for Functional Gastrointestinal Disorders: The Prevalence and Impact of Gastroesophageal Reflux Disease
- Cleveland Clinic: GERD and Asthma
- "Chest": Effects of 24 Weeks of Lansoprazole Therapy on Asthma Symptoms, Exacerbatins, Quality of Life, and Pulmonary Function in Adult Athmatic Patients with Acid Reflux Symptoms; M. Littner et. al.; Sept 2005
