Clinical characteristics and natural history of symptomatic but not excess gastroesophageal reflux

The clinical and economic impact of competing management strategies for gastro-oesophageal reflux disease

BACKGROUND

Gastro-oesophageal reflux disease (GERD) is a common disorder in the primary care setting. Traditional management strategies consist of sequentially intensive therapeutic trials followed by invasive diagnostic testing for nonresponders. A high dose proton pump inhibitor trial (the "proton pump inhibitor test") has been shown to be an accurate diagnostic alternative, and may be an efficient initial approach to patients with GERD symptoms.

AIM

To examine the clinical, economic and policy implications of alternative management strategies for GERD.

METHODS

Decision analysis was used to calculate the clinical and economic outcomes of competing management strategies. The traditional strategy incorporates sequential therapeutic trials with more intensive therapy ("step-up" approach) followed by sequential invasive diagnostic testing of nonresponders. The "proton pump inhibitor test" strategy includes an initial "proton pump inhibitor test" (7 days of omeprazole; 40 mg AM + 20 mg PM daily) followed by less intensive therapeutic trials in those testing positive ("step-down" approach) with sequential invasive diagnostic testing as needed. Cost estimates were based on Medicare reimbursement and average wholesale drug prices. Probability estimates were derived from a systematic review of the published medical literature. Model results are reported as the average and incremental cost-per-symptom free patient and cost-per-quality-adjusted life-years (QALYs) gained.

RESULTS

The average cost per patient was 1045 US dollars for the traditional step-up management strategy, compared to 1172 US dollars for the "proton pump inhibitor test" and step-down strategy. The percentage of patients who were symptom-free at 1 year was 50% for the traditional management strategy compared to 75% for the "proton pump inhibitor test" strategy. The "proton pump inhibitor test" strategy results in QALY gains of 0.01-0.05 depending on the utility estimate employed. The incremental cost-effectiveness ratio for the "proton pump inhibitor test" strategy is 510 US dollars per additional symptomatic cure over 1 year, and between 2822-10,160 US dollars per QALY gained. The traditional management strategy resulted in a greater than 5-fold increase in the utilization of upper endoscopy, which was partially offset by a 47% reduction in the use of ambulatory 24-h oesophageal pH monitoring. The reduced effectiveness of the traditional management strategy may be attributed in part to a 118% increase in the use of "high-dose" H2RAs while reducing the use of standard dose proton pump inhibitors by only 42% and "high-dose" proton pump inhibitors by 57%.

CONCLUSIONS

Based on the results of this analysis, strategies utilizing the initial PPI test followed by a "step-down" approach may result in improved symptom relief and quality of life over 1 year, and more appropriate utilization of invasive diagnostic testing at a small marginal increase in total costs. These findings warrant a prospective trial comparing these competing management strategies.

Gastroesophageal reflux disease: clinical, endoscopic, and intraluminal esophageal pH monitoring evaluation

One hundred and twenty-two patients with gastroesophageal reflux disease were studied (90 with and 32 without esophagitis) with the objective of analyzing possible differences between those with and without esophagitis. Evaluation consisted of clinical interview, endoscopy of the high digestive tract, esophageal manometry, and pH monitoring. There was no significant difference between the groups in age, sex, or symptoms. The incidence of hiatal hernia was greater in the group with esophagitis. Although the frequency of motor changes was similar, the type of anomaly was different. The reflux pattern was very similar in both groups. Therefore, the concept of reflux disease, esophagitis, and pathological reflux still needs a broader definition for greater diagnostic precision and for comparing the results of different studies on the subject. Normal reflux (confirmed using pH esophageal monitoring) in 12.2% of patients with esophagitis suggests that other factors are implicated in the etiology of the disease besides those measured using this examination.

Laparoscopic fundoplication for symptomatic but physiologic gastroesophageal reflux

Esophageal pH monitoring identifies some patients who have physiologic amounts of esophageal acid exposure but have a strong correlation between symptoms of esophageal reflux events. These patients with symptomatic physiologic reflux probably have enhanced sensory perception of reflux events and may be difficult to control with acid-suppressive therapy. Little is known about the role of fundoplication in such patients. Patients with no endoscopic evidence of gastroesophageal reflux disease and a normal 24-hour pH composite score (<22.4 in our laboratory), but a symptom index (SI = number of symptoms with pH <4/total number of symptoms) greater than 50% were offered laparoscopic fundoplication if acid-suppressive therapy was unsatisfactory. This group comprised 18 (4%) of 459 patients undergoing fundoplication at our institution. Heartburn, dysphagia, and reflux symptoms were scored on a scale of 0 to 10 with patients on and off medicine preoperatively, and at a mean of 7.2 months (range 1 to 32 months) postoperatively. The 18 patients with symptomatic physiologic reflux (6 males and 12 females) had heartburn as a major complaint. Preoperative response to proton pump inhibitors for heartburn was 72% and for all symptoms was 60%. The group had a mean pH composite score of 14 (range 4 to 22). The symptom used to calculate the symptom index was heartburn in 12 patients, regurgitation in three, chest pain in two, and cough in one. An average of 18 symptoms (range 2 to 56) were recorded. The mean symptom index was 82% (range 50% to 100%). A Nissen fundoplication was performed in nine patients and a Toupet fundoplication in nine. Surgery was successful (>90%) in alleviating reflux symptoms in 14 patients and partially successful (>75%) in three of the remaining four patients. Gas bloat and dysphagia were seen in one patient each. Fundoplication is effective at relieving reflux symptoms in carefully selected patients with symptomatic physiologic reflux, with minimal side effects.

Endoscopy-negative reflux disease

Endoscopy-negative reflux disease (ENRD) is more prevalent than reflux esophagitis, especially in a primary care setting. Acid-sensitive esophagus (ie, reflux-related symptoms with normal acid exposure at 24-hour pH monitoring) is part of the gastroesophageal reflux disease spectrum. ENRD is not a mild disease (symptoms return frequently and have an impact on quality of life), but it rarely progresses to the erosive stage. In patients with atypical or extra-esophageal manifestations, pH monitoring remains useful, and symptom analysis (symptom index or symptom-associated probability) is of pivotal importance. A proton pump inhibitor (PPI) test may represent a cost-effective alternative to 24-hour pH monitoring. However, well-designed validation studies are necessary to assess the diagnostic value of PPI tests and improve specificity without reducing sensitivity. Management of ENRD is based on the same principles as that of reflux esophagitis. Restoration of quality of life is the major goal. Proton pump inhibitors are not more (and are sometimes even less) effective in non-erosive reflux disease than in reflux esophagitis. Different long-term strategies (continuous maintenance, intermittent or on-demand therapy) are available, depending on the needs of the patient. Antireflux surgery may be indicated in carefully selected patients. In the future, pharmacologic approaches targeted to transient lower esophageal sphincter relaxation or visceral perception should be developed.

Laparoscopic antireflux surgery in the treatment of the acid-sensitive oesophagus

BACKGROUND

Approximately 10 per cent of patients referred for 24-h oesophageal pH tests with symptoms suggestive of gastro-oesophageal reflux disease will have a normal endoscopic examination and normal distal oesophageal acid exposure times, but a clear temporal correlation between their symptoms and episodes of acid reflux. These patients have an 'acid-sensitive oesophagus', which forms part of the spectrum of reflux-related conditions. Their response to antireflux surgery has not been reported previously. This study represents a prospective cohort analysis of a clearly defined group of patients with acid-sensitive oesophagus who have undergone laparoscopic antireflux surgery.

METHODS

Nineteen patients (nine male and ten female; median age 32 years) underwent laparoscopic antireflux surgery for acid-sensitive oesophagus. All had had an incomplete response to medical therapy.

RESULTS

Eighteen of 19 patients were graded Visick I or II at 6 months after operation; all 16 patients followed for 1 year were graded Visick I or II. There were significant falls in DeMeester symptom score (4.0 versus 0.5; P < 0.001), symptom events (20 versus none; P < 0.001), number of reflux episodes (17 versus two; P < 0.001) and overall acid exposure times (1.2 versus 0.3 per cent; P < 0.001) after operation.

CONCLUSION

Laparoscopic antireflux surgery is a valid and effective treatment for patients with an acid-sensitive oesophagus. Presented in poster form to the British Society of Gastroenterology, Birmingham, March 2000 and the American Gastroenterological Association, San Diego, May 2000

Nonerosive reflux disease--current concepts and dilemmas

Nonerosive reflux disease is defined as the presence of typical symptoms of gastroesophageal reflux disease caused by intraesophageal acid in the absence of visible esophageal mucosal injury at endoscopy. Recent studies demonstrate that it is a chronic disease with a significant impact on quality of life, and it is very common in primary care settings. Treatment with acid inhibitory agents is effective, and proton pump inhibitors are the most effective form of therapy.

Endoscopy-negative reflux disease

The majority of patients with symptoms of gastro-oesophageal reflux have no endoscopic evidence of oesophagitis. There has been remarkably little systematic gathering of information about this group of patients. It is commonly believed that they have a mild form of reflux disease, with low levels of dysfunction that usually respond to simple therapeutic measures. Emerging data from recent studies indicate that this is not the case. Endoscopy-negative patients have symptom severities comparable to those with erosive disease, and which significantly impair their quality of life. The limited data available on the pathophysiology of endoscopy-negative reflux disease suggest that, in the majority of patients, it is as much a disease of excessive gastro-oesophageal reflux as it is in patients with oesophageal lesions. The same principles that apply to successful treatment in patients with oesophagitis also hold true for patients with endoscopy-negative disease.

Epidemiology and natural history of reflux disease

Gastro-oesophageal reflux disease (GORD) is a highly prevalent condition in Western countries; at least 20% of the population have weekly symptoms. The incidence appears to be rising in the West and in some developing countries. Heartburn, based on a carefully elicited history, is reasonably specific for identifying GORD if it is a predominant complaint. Symptoms, however, appear to correlate poorly with oesophagitis; hence, severe symptoms do not indicate there is greater oesophageal damage. Only one-third to one-half of patients with GORD undergoing endoscopy have oesophagitis. GORD is usually a chronic disease but one-third may lose their symptoms over time. An ill-defined subset of patients over time may progress to develop abnormal acid exposure or oesophagitis, or both, when none existed at baseline. GORD has a significant negative impact on quality of life to the same degree as other chronic medical conditions, but impairment in quality of life is independent of oesophagitis.

Functional Gastroesophageal Reflux Disease (GERD)

Lack of endoscopic esophagitis does not exclude gastroesophageal reflux disease (GERD). Ambulatory pH testing is also an imperfect standard, and patients with both a normal endoscopy and a normal pH test may still have symptoms produced by acid reflux. A therapeutic trial of acid suppression is often the best approach to these patients. Ideally, therapeutic trials should use a medication with a high degree of efficacy in the treatment of GERD to avoid a false-negative test. Proton pump inhibitors (PPIs) are the best currently available medical therapy for all forms of GERD. If the patient does not respond to a once daily PPI, options include increasing the dose of PPIs, and, perhaps, adding another class of agent or studying the patient with an ambulatory pH test. Patients with a negative endoscopy, negative pH test. and those who do not respond to an adequate trial of acid suppression are unlikely to benefit from antireflux surgery.

Diagnostic evaluation in gastroesophageal reflux disease

Gastroesophageal reflux disease (GERD) describes the clinical manifestations of reflux of gastric contents and the associated symptoms and patterns of tissue injury. Although its exact prevalence is difficult to determine, there is no doubt the GERD is the most common esophageal disease and probably among the most prevalent conditions seen in the primary care setting. GERD has a wide clinical spectrum, making the diagnostic evaluation challenging and complicated at times. Confirmatory test are rarely needed in patients with typical symptoms of heartburn or regurgitation who have a good clinical response to GERD therapy. This article describes the diagnostic tests necessary for some cases of GERD.

Endoscopy-negative gastroesophageal reflux disease. The hypersensitive esophagus

Gastroesophageal reflux disease (GERD) is one of the mos common disorders of the gastrointestinal tract. Patients with GERD symptoms may exhibit a spectrum of endoscopic findings ranging from normal endoscopy (EGD negative) to severe ulcerative esophagitis. Recent evidence indicates that a large proportion of patients with GERD have normal endoscopy. The use of 24-hour ambulatory pH testing in the evaluation of symptomatic patients with EGD negative GERD allows further classification of these subjects into groups. Patients who have abnormal acid exposure and a positive symptom index constitute one group and patients who have normal acid contact time but record a convincing relationship between their symptoms and acid reflux on the pH analysis--positive symptom index--form another group. The latter group has been suggested to have a hypersensitive esophagus or "functional heartburn." This article reviews the prevalence, clinical features, origin of patient's symptoms, natural history, and treatment of patients with EGD negative GERD.

Esophageal sensitivity and symptom perception in gastroesophageal reflux disease

Patients with gastroesophageal reflux disease (GERD) experience a wide spectrum of symptoms, varying both in quality and severity. This review summarizes clinical observations of esophageal sensitivity and symptom perception in GERD patients. The Bernstein test, although lacking standardization, remains a useful tool in determining esophageal sensitivity to acid stimuli. Ambulatory 24-hour pH monitoring with symptom event marking and subsequent symptom-reflux correlation between acid reflux events and esophageal symptomatology now provides an alternative method for establishing esophageal acid sensitivity. The intraesophageal balloon distention test (IEBD) was developed to assess esophageal sensitivity to mechanical stimuli. Variants of each of these tests have been applied to the evaluation of uncomplicated GERD patients and patients with esophagitis and Barrett's metaplasia, who generally demonstrate less esophageal sensitivity than the former group. Studies using these methods have demonstrated increased esophageal sensitivity in patients with esophageal chest pain and have also identified a subset of patients with esophageal symptoms yet normal esophageal acid exposure, a condition referred to as "hypersensitive esophagus." The Bernstein test, 24-hour pH monitoring with symptom assessment, and IEBD have each contributed to our understanding of esophageal pain syndromes; it is hoped that future work in this area will lead to improved and more specific therapy for these patients.

The epidemiology of functional gastrointestinal disorders in North America

This article has summarized the epidemiology of several disorders commonly seen in a gastroenterologist's practice. The emphasis has been on population-based data because many people with these disorders never seek health care, and psychological features have been shown to be strongly associated with health care-seeking behavior. Each of these disorders is common in the community; in fact, the majority of the population experiences intermittent gastrointestinal symptoms. In general, the national surveys sponsored by the U.S. Public Health Service have been shown to underestimate the prevalence of these conditions. In part, this is due to the fact that subjects are asked to report diagnoses rather than symptoms, and current coding schemes do not provide specific codes for each of the functional gastrointestinal disorders. Still, these studies have demonstrated the large number of physician visits and overall costs attributable to these disorders. A number of surveys of more limited populations have been done to assess the prevalence of these disorders. Rates have varied because of the definitions used and the degree to which organic diagnoses are excluded. These studies have been helpful in demonstrating the burden of illness in the community. Age and gender differences in the community have been much less marked than those identified in clinic-based studies, thus highlighting the importance of population-based research. Future studies need to focus on the incidence and natural history of these disorders. Studies of incidence cases can best evaluate the role of etiologic factors, whereas studies of prevalent cases are best for assessing the burden of disease in the community. Understanding the natural history of these disorders is important in determining the efficacy of future therapeutic interventions. The fact that these disorders represent 50% of visits to a gastroenterologist practice highlights the importance of these disorders and the potential contribution of gastrointestinal dysmotility in clinical practice.

Esophageal motility and reflux testing. State-of-the-art and clinical role in the twenty-first century

Esophageal function testing has an important place in the investigation of a significant proportion of patients with esophageal disorders. Appropriate application of these tests requires a proper understanding of their capabilities and limitations and careful primary assessment by other modalities. Esophageal manometry is most useful for assessing significant troublesome dysphagia in the absence of organic obstruction. Esophageal pH monitoring is an important adjunct to clinical assessment and endoscopy in the diagnosis of reflux disease. Although it is the gold standard for the measurement of esophageal acid exposure and assessment of the relationship of symptoms to reflux, there are weakness in both of these functions that should be understood when applying the test to the diagnosis of reflux disease.