Gastroesophageal reflux disease (GERD) is defined as symptoms or tissue damage that results from the abnormal reflux of gastric contents into the esophagus. A systematic review of population-based studies estimates that heartburn or regurgitation symptoms occur in 21% to 59% of the population during a given year.1 The frequency of GERD in specific populations is provided in Table 1. Although only 1 in 5 patients with upper intestinal symptoms that occur at least weekly seeks medical attention,2 nearly 1% of all visits to a family physician’s office are for GERD or related conditions.3
GERD significantly affects the quality of patients’ lives. In a survey of patients presenting for upper endoscopy with symptoms of at least 3 months’ duration, those with a diagnosis of GERD reported low scores at baseline for general wellbeing. Fortunately, follow-up data reported 4 weeks after treatment note improvement in gastrointestinal symptoms, general well-being, general health, vitality, and depression.4
Pathophysiology
The pathogenesis of GERD is multifactorial and is thought to involve lower than normal esophageal sphincter pressures. This allows gastric acidic content to reflux into the distal esophagus, which lacks a protective barrier, causing esophagitis. Inflamed tissue impairs the normal clearance of acid, worsening the esophagitis, which inhibits normal motility.
Although Helicobacter pylori is clearly associated with peptic ulcer disease, its association with GERD is still debated. Data from case control studies actually suggest an inverse association; that is, that the presence of H pylori may be protective against the development of GERD.5
Because of the anatomical location of the esophagus, GERD should be considered in the differential diagnosis for presenting complaints other than regurgitation or dyspepsia. For example, approximately 50% of patients with chest pain in whom cardiac etiology is ruled out will ultimately be given a diagnosis of GERD.6 Similarly, 10% of patients with chronic cough7 and 78% of patients with laryngitis have GERD.8 Clear associations between GERD and asthma have been demonstrated, but data from meta-analyses fail to show improvement of asthma symptoms when GERD is appropriately treated.9
Diagnosis
The diagnosis of GERD can usually be made without the use of invasive tests. The accuracy of key tests, including clinical history, is outlined in Table 2. One study of patients presenting with dyspepsia (signs and symptoms referable to the upper gastrointestinal tract) found that 56% also have GERD.10 Another showed that 60% of patients referred for pH monitoring had GERD.11 Since reasonable prevalence estimates for GERD in the family practice setting may be slightly lower, calculations in Table 2 assume that between 40% and 60% of patients with suspected GERD actually have the condition.
Individual symptoms of GERD such as heartburn, regurgitation, belching, or dyspepsia are of limited usefulness in diagnosis. In a survey of patients referred for pH monitoring likelihood ratios hovered near 1, meaning that the presence or absence of the symptom had little impact on the diagnosis.11 The clinician’s overall impression that a patient has GERD, however, is much more useful to rule in disease than any individual symptoms.11 Assuming that half of patients with suspected GERD have the disease, if a clinician suspects GERD, that probability increases to 77%. Most clinicians would find a trial of empiric therapy appropriate at that probability.
The omeprazole test is also helpful in confirming a diagnosis of GERD. It consists of the patient taking 40 mg omeprazole in the morning and 20 mg at night for 1 week. If the symptoms resolve, the test is considered diagnostic of GERD.12 Some consider this approach to be therapeutic, as well as diagnostic. Beginning with an omeprazole test and reserving invasive testing for those not responding to the medication was cost-effective for patients with noncardiac chest pain.13 In a decision analysis, empiric treatment with omeprazole was a cost-effective approach to the management of GERD.14 Of course, initial endoscopy is indicated for patients with “red flags”: signs and symptoms consistent with obstruction, bleeding, or perforation, and those older than 50 years who are at a higher risk of malignancy.
Upper endoscopy, however, is not very accurate in diagnosing GERD. Among patients with GERD, only 22% have esophageal erythema, and only 48% have erosions or ulcerations. Therefore, because of costs and limited resources, the American Society for Gastrointestinal Endoscopy recommends that endoscopy be reserved for patients presenting with possible GERD who also have symptoms of more serious disease (dysphagia, weight loss, gastrointestinal bleeding) and for those not responding to a reasonable trial of therapy.15 The goal is to rule out more serious conditions.
Twenty-four–hour pH monitoring, while more accurate than endoscopy, is also reserved as a second-line test. According to the American Gastro-enterological Association guidelines, pH recording is indicated when endoscopy is normal and reflux symptoms persist despite acid suppression therapy or to evaluate extra-esophageal symptoms that may be GERD (ie, atypical chest pain or chronic cough).16 The goal here is to rule in GERD as the etiology of the patient’s symptoms.