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American College of Gastroenterology
Update Guidelines for the Diagnosis and Treatment of Gastroesophageal Reflux Disease
Updated Guidelines for the Diagnosis and Treatment of Gastroesophageal Reflux Disease Kenneth R. DeVault, M.D., F.A.C.G., Donald O. Castell, M.D., F.A.C.G., and The Practice Parameters Committee of the American College of Gastroenterology
Preamble Guidelines for the diagnosis and treatment of gastroesophageal reflux disease (GERD) were published by the American College of Gastroenterology in 1995 (1). These and other guidelines undergo periodic review. Significant advances have been made in the area of GERD over the past several years, leading us to review and revise our previous guidelines statements. These advances have included an increase in our comfort with the chronic use of proton pump inhibitors and an increased acceptance of laparoscopic antireflux surgery, among other factors. These and the original guidelines are intended to apply to all physicians who address GERD and are intended to indicate the preferable, but not only acceptable, approach. Physicians must always choose the course best suited to the individual patient and the variables that exist at the moment of the decision. These guidelines are intended to apply to adult patients with the symptoms, tissue damage, or both that result from the reflux of gastric contents into the esophagus. For the purpose of these guidelines GERD is defined as chronic symptoms or mucosal damage produced by the abnormal reflux of gastric contents into the esophagus. Both these and the original guidelines were developed under the auspices of the American College of Gastroenterology and its Practice Parameters Committee, and approved by the Board of Trustees. The world literature was reviewed extensively for the original guidelines and was once again reviewed using the National Library of Medicine database. All appropriate studies were reviewed and any additional studies found in the reference list of these papers were obtained and reviewed. Evidence was evaluated along a hierarchy, with randomized controlled trials given the greatest weight. Abstracts presented at national and international meetings were only used when unique data from ongoing trials were presented. When scientific data were lacking, recommendations were based on expert consensus. During preparation, the guidelines were reviewed by the American Gastroenterological Association and the American Society for Gastrointestinal Endoscopy. Recommendations and comments obtained from these reviews were incorporated into the final document whenever possible.
Empiric Therapy for GERD Old If the patient's history is typical for uncomplicated GERD, an initial trial of empirical therapy (including lifestyle modification) is appropriate. Patients in whom empirical therapy is unsuccessful or who have symptoms suggesting complicated disease should have further diagnostic testing. New If the patient's history is typical for uncomplicated GERD, an initial trial of empirical therapy (including lifestyle modification) is appropriate. Patients in whom empirical therapy is unsuccessful, or who have symptoms suggesting complicated disease, should have further diagnostic testing. Selected individuals who have longstanding symptoms or who require continuous therapy may need endoscopic screening for Barrett's esophagus. Symptoms that are highly specific for GERD (when the predominant or only symptoms) include heartburn (pyrosis), regurgitation, or both, which often occur after meals (especially large or fatty meals) (2). These symptoms are often aggravated by recumbency or bending and are relieved by antacids. The combination of symptoms and endoscopic changes are highly specific (97%) for GERD (confirmed with pH testing) (3). Expert opinion holds that it is appropriate to offer empirical therapy for GERD to patients with symptoms consistent with GERD. It is also reasonable to assume a diagnosis of GERD in patients who respond to appropriate therapy. Further diagnostic testing should be considered under four circumstances: lack of response to therapy, warning symptoms (Table 1), chronic symptoms in a patient at risk for Barrett's esophagus, or need for continuous chronic therapy. Patients who do not respond to therapy often have another cause for their symptoms, but this lack of response does not always exclude reflux as a possibility. Even when the most effective therapy for GERD is prescribed, some patients will continue to reflux acid (4). The purpose of evaluating patients who have warning symptoms is to exclude complications of GERD (esophageal strictures, carcinomas, etc). Other guidelines have been published that examine Barrett's esophagus in detail (5). In brief, certain patients with long-term symptoms (either with or without therapy) are at an increased risk for the development of Barrett's esophagus. Because we cannot be assured that partial (or even complete) control of acid changes this progression, the number of years of antireflux therapy may need to be considered in the calculation of when to search for Barrett's esophagus. The concept of symptoms predicting the presence of Barrett's esophagus has been challenged by reports suggesting that both the frequency and severity of reflux symptoms are poorly predictive of the presence of Barrett's esophagus (6). Table 1. Warning Symptoms Suggesting Complicated GERD
Dysphagia Bleeding Weight loss Choking (acid causing coughing, shortness of breath , or hoarsness) Chest pain
Endoscopy in GERD Old Endoscopy with biopsy is the primary technique for evaluating mucosal integrity. If unavailable, double-contrast radiography may be used. New Endoscopy is the technique of choice for evaluating the mucosa for esophagitis. The diagnosis of Barrett's esophagus requires biopsy to search for intestinal metaplasia. Endoscopy allows direct visualization of the esophageal mucosa. This is the only reliable method for the diagnosis of Barrett's esophagus. A reticular pattern on barium esophagram is neither sensitive (26%) nor specific (50%) when compared with endoscopy with biopsy (7). Barium radiography is reasonably accurate in cases of severe (98.7%) or moderate (81.6%) esophagitis, but is much less accurate with mild esophagitis (24.6%) (8, 9, 10, 11). Finally, reflux of barium during radiographic evaluation is only positive in 25-75% of symptomatic patients and is falsely positive in as many as 20% of normal controls (12, 13). Patients with hiatal hernias or who reflux barium at fluoroscopy have more acid exposure by ambulatory pH testing, but these findings have poor specificity and sensitivity and should not be used as a screening test for GERD (14). These factors limit the usefulness of barium radiography in the routine diagnosis of GERD. Endoscopic biopsy is needed to determine the presence of Barrett's epithelium. The issues surrounding both routine and short-segment Barrett's are covered in another guidelines statement (5). Patients with both typical and atypical manifestations of GERD will often have normal-appearing esophageal mucosa. These cases must be confirmed with other methods (pH testing or therapeutic trial). There is little value for histological examination of normal-appearing squamous mucosa to either confirm or exclude pathological acid reflux (15, 16).
pH and Provocative Testing No Change Ambulatory pH testing helps to confirm gastroesophageal reflux in patients with persistent symptoms without evidence of mucosal damage and with noncardiac chest pain or reflux-associated pulmonary and upper respiratory symptoms, and to monitor the esophageal acid exposure of a patient with refractory symptoms. Provocative tests have a limited usefulness in the routine diagnosis and therapy of GERD. Although endoscopy allows for the evaluation of esophageal mucosa, the presence or absence of mucosal injury does not provide proof that the patient's symptoms are or are not related to GERD. Many patients with typical GERD symptoms and increased esophageal acid exposure do not have esophagitis (17). Patients with symptomatic, but not excessive, gastroesophageal reflux have persistence of symptoms and requirements for therapy similar to patients with excessive reflux, but are less likely to have endoscopic findings (18, 19). This endoscopic-negative form of GERD produces symptoms and illness behavior identical to that of GERD with endoscopic findings (20). Ambulatory pH testing allows the identification of patients with excess esophageal acid exposure and those with symptoms that correlate with esophageal acid (with either normal or abnormal total acid exposure). Good reproducibility (84-93%) and sensitivity and specificity (96%) have been reported (21, 22). Some additional papers have provided cause for concern. Normal acid exposure was reported in as many as 29% of patients with documented esophagitis and differences were found in the simultaneous acid exposure recorded by two attached probes (23, 24). Despite these limitations, ambulatory pH testing remains the best method to study the actual amount of reflux occurring in a given patient. Patients with typical reflux symptoms and a normal endoscopy, but who respond to antireflux therapy, will not benefit greatly from a pH study. Ambulatory pH testing while taking reflux therapy may also be of benefit in the patient with refractory symptoms (25). The most commonly used provocative test of the esophagus is the Bernstein test of mucosal sensitivity to acid. If the subject's symptoms are provoked by acid and not by a normal saline control, the test is highly specific for GERD, but unfortunately much less sensitive (26). The Bernstein test may therefore establish that a patient's symptoms are related to GERD, but cannot exclude reflux and also cannot differentiate between degrees of reflux or esophagitis. An empirical trial of therapy with full- or double-dose proton pump inhibitor (PPI) has been suggested as a "test" for GERD. Relief of symptoms with 1 wk of omeprazole 20 mg twice daily had a sensitivity of 75% and a specificity of 55% when compared with endoscopy and ambulatory pH testing (27). In another study, using pH as the gold-standard, an omeprazole trial had a positive and negative predictive value of 68% and 63%, respectively, and when the omeprazole trial was considered the standard, the pH test had identical positive and negative predictive values (28). Neither a PPI trial nor ambulatory pH testing should be considered to provide absolute proof or disproof of GERD and in difficult cases both may be needed for the highest diagnostic certainty. An empirical trial of PPI has also been advocated as a diagnostic test in patients with atypical symptoms or signs such as chronic laryngitis (29) or unexplained chest pain (30).
Esophageal Manometry Old Esophageal manometry is indicated and in certain complicated cases may be helpful before an antireflux procedure is performed. New Esophageal manometry should be used to facilitate placement of ambulatory pH probes and to guide antireflux surgery. The accurate placement of esophageal pH probes requires knowledge of the location of the lower esophageal sphincter (LES) (31, 32). This usually requires intubation with a manometry catheter and provides an opportunity for full manometry. There now have been several reports that show adequate placement of pH tubes using a combined pH/pressure measurement system, which negates the need for full manometry (33, 34). Esophageal manometry to document the presence of effective esophageal peristalsis is useful in patients in whom antireflux surgery is being considered (35). Patients who have ineffective peristalsis may need to either avoid surgery or undergo an alternative (i.e., less tight) procedure (36). In a series of 107 patients, manometry changed the therapy offered in 10% of patients referred for antireflux surgery (37). Surgeons will often elect to perform a partial fundoplication in patients who have peristaltic dysfunction of the esophagus by manometry (38). These reports suggest, but do not prove, that better reflux control is achieved with a complete (Nissen) fundoplication than with a partial (Toupet) and that in a patient with less effective esophageal peristalsis, the risk of dysphagia is higher with the complete fundoplication. If these assumptions are true, manometry should be mandatory before fundoplication to choose the best surgery for the individual patient. Absolute LES pressure has been suggested to inversely correlate with esophageal acid exposure. This has been challenged by more recent reports suggesting esophageal body dysfunction to be a better predictor of abnormal acid exposure (39).
Lifestyle Modification No Change Lifestyle modification should be initiated and continued throughout the course of GERD therapy. Numerous studies have indicated that elevation of the head of the bed (40, 41), decreased fat intake (42), cessation of smoking (43), and avoiding recumbency for 3 h postprandially (44) decrease distal esophageal acid exposure, although data reflecting the true efficacy of these maneuvers in patients is almost completely lacking. Certain foods [chocolate (45), alcohol (46), peppermint (47), coffee (48), and perhaps onions and garlic (49)] have been noted to increase esophageal reflux and should be avoided, although randomized trials are also not available to test the efficacy of these maneuvers. Weight loss has been suggested to improve reflux, but studies have not been able to provide objective evidence of this association (50). Many authors assume the 20-30% placebo response rate seen in most randomized trials is due to lifestyle changes, but this has not been tested. Neither the efficacy nor the potential negative effect of lifestyle changes on a patient's quality of life have been adequately examined for any of the maneuvers. Despite this lack of data, expert opinion holds that education of the patient about factors that may precipitate reflux is reasonable.
Patient-Directed Therapy New Antacids and over-the-counter acid suppressants are appropriate, initial patient-directed therapy for GERD. If symptoms persist while on therapy or warning signs develop (Table 1), the patient should undergo a diagnostic evaluation (see earlier diagnostic guidelines). Antacids and antirefluxants such as alginic acid are useful in the treatment of milder forms of GERD. Antacids (51) and alginic acid (52, 53) have been shown to be more effective than placebo in the relief of symptoms induced by a heartburn-promoting meal. In addition, combined antacid/alginic acid therapy may be superior to antacids alone in the control of symptoms (54, 55). There are two long-term trials that suggest effective symptom relief in approximately 20% of patients using over-the-counter agents (56, 57). All four of the histamine type-2 receptor antagonists (H2RAs) approved for use in the United States are now available in an over-the-counter (OTC) form at a dose that is usually one-half of the standard prescription dose. These doses have been shown to decrease gastric acid, particularly after a meal. Though there are some differences in potency, duration, and rapidity of action, they may generally be used interchangeably. The OTC H2RAs are particularly useful when taken before an activity that may potentially result in reflux symptoms (heavy meal or exercise in some patients). Many patients can predict when they are going to suffer from reflux and can premedicate with the OTC H2RAs. Famotidine 10 mg taken before an evening meal has been demonstrated to prevent reflux and restore sleep in patients who are usually awakened by GERD (58). Comparisons between OTC H2RAs and antacids are limited. It has been suggested that antacids provide a more rapid response, but gastric pH begins to rise less than 30 min after taking a dose of H2RA so this does not seem to be a major factor. The peak potency of OTC H2RAs and antacids are similar, but the H2RAs have a much longer duration of action (up to 10 h).
Acid Suppression for GERD Old Acid suppression is the mainstay of therapy for GERD. Histamine2-receptor blockers given in divided doses are effective treatment in many patients. Proton pump inhibitors provide rapid symptomatic relief and healing of esophagitis in the highest percentage of patients. New Acid suppression is the mainstay of therapy for GERD. Proton pump inhibitors provide rapid symptomatic relief and healing of esophagitis in the highest percentage of patients. Histamine2-receptor blockers given in divided doses may also be used and are effective treatment in many patients with less severe GERD. In the original guideline statement, the results of 33 randomized trials with more than 3000 patients are presented. Symptomatic relief can be expected in 27% of placebo-treated, 60% of H2RA-treated, and 83% of PPI-treated patients. Esophagitis healed in 24% of placebo-treated, 50% of H2RA-treated, and 78% of proton pump inhibitor-treated patients. We will not readdress those studies here, but it is clear that whereas some patients will have relief of symptoms and improvement or healing of esophagitis with H2RAs, PPIs eliminate symptoms and heal esophagitis more frequently and more rapidly than the other agents. Both higher doses and more frequent dosing of H2RAs appear to be more effective in the treatment of reflux symptoms and healing of esophagitis, but these agents are still inferior to proton pump inhibitors and more costly at higher dosages (59, 60, 61). Concerns about the use of PPIs surround the profound decrease in gastric acid secretion produced by these medications (62). This leads to an increase in gastrin production from the antral-G cells and sustained increases in serum gastrin, usually to a mild degree (two to four times basal) (63). The question of whether these changes in serum gastrin might produce dangerous trophic effects on the gastric mucosa with long-term use of PPIs remains to be completely resolved, although both omeprazole and lanzoprazole are now approved for 1 yr of continuous usage. The experience with PPIs is approaching a decade in the United States and much longer in Europe and Australia. There has not been a reported case of gastric carcinoid type tumor in a patient receiving a PPI, with the exception of cases who had a multiple endocrine neoplasia syndrome not felt to be related to the drug. Atrophic gastritis has been reported with long-term omeprazole therapy. It was recently reported that these patients were often infected with Helicobacter pylori (64), but the clinical relevance of these findings has been questioned and essentially discounted (65). Cobalamin absorption may be decreased with chronic PPI therapy, but no change in serum levels have been reported after as many as 7 yr of therapy (66). There has also been no evidence of bacterial overgrowth after long-term acid suppression (67). It is becoming increasingly clear that the potential benefit of chronic PPI therapy in patients with chronic or complicated GERD outweighs any theoretical risk. There is much debate over the role of H2RAs and PPIs in the initial treatment of GERD. One approach, the so called step-up therapy, is to start with a standard or even OTC dose of H2RA and titrate to symptom control. The other approach, step-down therapy, starts with once- or perhaps twice-daily proton pump therapy and decreases the therapy to the lowest form of acid suppression that controls the symptoms. There have been models constructed to evaluate both the efficacy and cost-effectiveness of these approaches and neither has been proven superior, therefore the approach is best left to the choice of the individual practitioner in consultation with the patient (68, 69).
Promotility Therapy for GERD Old Promotility agents such as cisapride and domperidone have an efficacy similar to standard-dose histamine receptor blockers. New The available promotility agents (cisapride and metoclopramide) have an efficacy similar to standard-dose histamine receptor blockers. Defects in esophagogastric motility (LES incompetence, poor esophageal clearance, and delayed gastric emptying) are central to the pathogenesis of GERD (70). If these defects could be corrected, then GERD would be controlled, making suppression of normal amounts of gastric acid unnecessary. Bethanechol may increase LES pressure to a small degree, but has limited efficacy in GERD. The frequent central nervous system side effects of metoclopramide (drowsiness, irritability, extrapyramidal effects, etc.) have, appropriately, decreased the regular use of this medication (71). Cisapride (10 mg q.i.d.) can provide effective symptomatic relief and healing of esophagitis, with results comparable to cimetidine 400 mg q.i.d. or ranitidine 150 mg b.i.d., and superior to placebo (72, 73, 74). Combined therapy with cimetidine and either metoclopramide (10 mg q.i.d.) (75) or cisapride (10 mg q.i.d.) (76) have been shown to result in improved healing of esophagitis, compared with cimetidine alone. Cisapride may also be an effective maintenance therapy for GERD (77, 78). A combination of cisapride and ranitidine was superior to ranitidine alone in the maintenance therapy of GERD, but inferior to omeprazole alone (79). Contrary to the positive studies cited, postprandial reflux as measured with ambulatory pH monitoring was not decreased in patients treated with cisapride, compared with controls (80).
There have been reports of fatal cardiac dysrhythmias associated with the combination of cisapride and several agents that are metabolized by the cytochrome P-450 system (particularly antifungal agents and some antimicrobials) (81, 82). The widespread use of this medication throughout the world suggests that these important side effects must be relatively rare. Although cisapride may be useful in certain patients with a combination of symptoms (nausea and constipation, among others), PPIs provide greater control of acid reflux, without the risk, albeit small, of cardiac rhythm disturbances.
Maintenance Therapy for GERD Old Because GERD is a chronic condition, therapy with acid suppression or promotility agents or both at the lowest dose needed to control symptoms and prevent complications is appropriate. This may include chronic proton pump inhibitor therapy. New Because GERD is a chronic condition, continuous therapy to control symptoms and prevent complications is appropriate. Chronic proton pump inhibitor therapy is an effective and appropriate form of maintenance therapy in many patients. Many, perhaps most, patients with GERD require long-term, possibly life-long, therapy. Therefore, maintenance therapy becomes a major concern. Effective maintenance therapy should keep the patient's symptoms comfortably under control and prevent complications. This will vary in each patient and may require only antacids and lifestyle modifications in as many as 20% of patients. Other patients with chronic reflux (50%) have frequent symptomatic relapses despite appropriate therapy. Patients whose disease has been controlled with PPIs often will have symptomatic relapses and failure of healing of esophagitis with a standard dose, or even higher-dose H2RA or prokinetic therapy (83). A full dose of H2RA given once daily, although effective for peptic ulcer disease, is not appropriate for GERD. Reduced doses of PPIs have not been shown consistently to be effective long-term in the therapy of GERD. This includes alternate-day omeprazole (84) or so-called weekend therapy (85). A daily dose of 10 mg may be superior to standard-dose ranitidine (86). The frequent marked improvement in GERD symptoms noted with the acid suppression produced by full-dose PPI is usually followed by a rapid return of symptoms once it is discontinued (87). There are clear data that acid suppression decreases the recurrence of peptic esophageal strictures. Cimetidine 400 mg four times a day did not affect the frequency of the need for dilation (88), but several studies have found that full-dose PPIs will lengthen the interval between symptomatic relapses (89, 90). There are no similar data in regards to the prevention or prevention of progression of Barrett's esophagus. It does not appear that Barrett's esophagus will regress with either medical or surgical therapy (91, 92). There have been reports of occasional islands of squamous epithelium appearing with chronic PPI therapy, but the significance of this is not known (93). Abnormalities of esophageal peristalsis have long been thought to predispose to reflux, but recent studies suggest that at least a portion of these motility disorders are in fact a consequence of the reflux and may improve while taking antireflux therapy (94).
Surgical Therapy for GERD Old Surgery should be considered if medical therapy fails or is deemed appropriate in individual cases. New Antireflux surgery, performed by an experienced surgeon, is a maintenance option for the patient with well-documented GERD. Considerable controversy exists over the long-term effectiveness of surgical intervention in GERD and whether it is superior to chronic medical therapy. In the two published trials of medical versus surgical therapy, surgery has been shown to be more effective. The initial comparison favored surgical over a rather modest medical therapy (essentially antacids and lifestyle changes) over a 36-month period (95). A comparison of surgery versus ranitidine and metoclopramide indicated superiority for the surgical approach (96). Preliminary results of a similar comparison between surgery and PPIs were recently presented. This randomized trial of 310 patients, who initially had their disease controlled with omeprazole 40 mg per day, found surgery to be slightly superior (maintenance of esophagitis healing and symptoms) to omeprazole 20 mg per day at the end of 3 yr (97). If dose titration up to 40-60 mg per day of omeprazole was used the two treatments were equal. Proper selection and preoperative evaluation of patients is very important. If typical reflux esophagitis is not present endoscopically, ambulatory pH testing should be performed. Esophageal manometry may alter the surgical decision in as many as 10% and should be a routine procedure before antireflux surgery. Delayed gastric emptying has been reported to increase the rate of complication after an antireflux surgery, but the utility of the routine preoperative use of these tests is not clear (98). The medical therapy of GERD has focused on the neutralization of refluxed acid from the stomach. It is clear that there are other injurious factors involved. The possibility of duodenogastroesophageal reflux (alkaline reflux) has been raised as an additional indication for the surgical repair of the LES in patients with GERD (99). Although it appears that control of acid decreases the injury in patients who reflux duodenal contents (100, 101), certain of these patients may benefit from antireflux surgery although objective evidence of this type of reflux is difficult to obtain preoperatively. A laparoscopic approach to antireflux surgery is rapidly evolving and appears to be equal or perhaps even superior to the open approach (102, 103, 104). A recent study found significantly lower cost and shorter lengths of hospital stay with the laparoscopic approach, although patient satisfaction was similar between the open and laparoscopic groups (105). This approach may not be possible in some patients who have had previous surgery and in the very obese. The decreased postoperative morbidity involved in this approach should not change the indications or evaluations for surgery, but does make this option more attractive for some patients whose alternative would be long-term medical therapy (106). The long-term durability of laparoscopic antireflux surgery remains incompletely defined, but several studies of the open technique have reported adequate control of disease for as long as 20 yr (107, 108). Another study suggested a deterioration in both LES pressure and endoscopic histology back toward the presurgical level 5-6 yr postoperatively (109).
GERD Refractory to Therapy New GERD refractory to medical therapy is very rare. The diagnosis should be carefully confirmed before chronic high-dose acid suppression or antireflux surgery. The vast majority of patients will have their symptoms and mucosal disease controlled with medical therapy for GERD. When a patient presents with either typical or atypical symptoms of GERD refractory to therapy, the diagnosis, current therapy, or both should be reconsidered. This may involve an ambulatory pH study, either with or without therapy, additional endoscopic and manometric evaluations, and consideration of testing and therapeutic trials for other conditions that may produce symptoms similar to GERD. Although PPIs provide outstanding acid control in the vast majority of patients, there has been a recent report of two patients who had refractory reflux (by pH study and symptoms) while taking omeprazole, who had better acid suppression with high-dose H2-receptor therapy (110). These cases are rare, but emphasize the need for individualized therapy and testing when symptoms consistent with GERD are refractory to therapy.
Extraesophageal Manifestations of GERD New GERD should be considered in the differential diagnosis of unexplained cases of chronic chest pain, cough, hoarseness, and asthma. Several other symptoms may be related to GERD and are usually referred to as atypical or extraesophageal symptoms of GERD. An association with GERD may occur in as many as 50% of patients with noncardiac chest pain (111), 78% of patients with chronic hoarseness (112), and 82% of patients with asthma (113). Chronic cough has also been associated with GERD (114, 115). Gastroesophageal reflux may be induced by exercise and can either be asymptomatic or present with typical or atypical symptoms (116, 117). Dental erosions have been associated with asymptomatic gastroesophageal reflux as well (118). These patients may or may not have typical symptoms of GERD and are often best diagnosed with either an empirical trial of therapy, ambulatory pH testing, or, in some cases, both. It has been suggested that these patients may require higher doses of acid suppression and longer therapeutic trials than patients with more typical symptoms of GERD. Finally, when these symptoms are refractory to medical therapy, the diagnosis of GERD needs to be carefully reconsidered before recommending surgical therapy.
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