A cost-effectiveness analysis of prescribing strategies in the management of gastroesophageal reflux disease

Review article: the pharmacodynamics and pharmacokinetics of proton pump inhibitors--overview and clinical implications

During the past two decades, enormous changes occurred in the management of gastric acid-related diseases. First, the histamine2-receptor antagonists were introduced, offering patients the first single-agent therapy that effectively reduced gastric acid secretion. Proton pump inhibitors became widely available in the early 1990s, and they generally appeared to be superior to the histamine2-receptor antagonists in acid-suppressing activity, symptom control and healing. Most physicians now use proton pump inhibitors as first-line treatment for many patients with acid-peptic disorders, including erosive gastro-oesophageal reflux disease (GERD), nonerosive reflux disease (NERD) and duodenal and gastric ulcers. Although proton pump inhibitors are often thought to be interchangeable, some differences have emerged in their pharmacological properties, which may be reflected in some aspects of clinical efficacy. Such differences include potency, speed of onset and duration of pH 'holding times'. Helicobacter pylori has now been recognized as an important factor in the pathogenesis of acid-peptic disorders. It is clear that H. pylori eradication can dramatically reduce the chronicity of gastric and duodenal ulcers, and accepted therapeutic regimens for H. pylori eradication now include proton pump inhibitors and two or more antibiotics. Although all accepted proton pump inhibitor-based 'triple therapies' are roughly equivalent in efficacy, there is now a shortened regimen available that will potentially enhance compliance and decrease cost. This review examines the relative advantages of proton pump inhibitors vs. histamine2-receptor antagonists in the context of acid suppression and in various gastric acid-related diseases. A brief overview presents the pharmacodynamics and pharmacokinetics of the proton pump inhibitors with particular attention paid to rabeprazole, one of the newer drugs in its class.

Management strategies for gastroesophageal reflux disease

In the treatment of gastroesophageal reflux disease (GERD), the most effective treatment option is the use of proton pump inhibitor (PPI), which minimizes the effect of gastric acid on the distal esophagus. Both the step-up and step-down treatment strategies have advantages and disadvantages. Most physicians would like to choose the step-down therapy rather than the step-up therapy. The 'No-step' PPI therapy (i.e. continuous PPI therapy) is another relevant option. After an initial remission, long-term PPI therapy is an appropriate form of maintenance therapy in many patients. As a treatment plan for non-erosive reflux disease, a standard dose of PPI for 4-8 weeks followed by either the step-down strategy or the on-demand treatment strategy is acceptable. When treating erosive esophagitis, PPI is better than H(2) receptor blockers in healing mucosal breaks and relieving symptoms. Long-term maintenance PPI therapy is reported to be very effective in maintaining the remission of reflux esophagitis for up to 5 years. On-demand PPI is also another good option for a maintenance therapy in erosive esophagitis. In Barrett's esophagus, symptoms seem to be well-controlled with PPIs. Unfortunately, however, PPIs have no effect on the shortening of Barrett's esophagus or in preventing the progression to dysplasia and adenocarcinoma. In summary, after reviewing existing guidelines a rather simple guideline on the management of GERD is suggested - PPI should be given for 4-8 weeks followed by either on-demand or maintenance PPI therapy according to the clinical severity.

Personal view: rationale and proposed algorithms for symptom-based proton pump inhibitor therapy for gastro-oesophageal reflux disease

Gastro-oesophageal reflux disease and non-erosive reflux disease are chronic, highly prevalent conditions requiring long-term treatment that is both effective and practical. On-demand therapy with a proton pump inhibitor may meet that need. It is becoming a mainstay of long-term treatment because it reduces the risk of over- and under-treatment, is cost-effective and user friendly. Epidemiological and clinical observations speak also in its favour. However, for the anticipated benefits of on-demand therapy to accrue in clinical practice, on-demand treatment algorithms are required. These algorithms must specify the initial evaluation and treatment of candidates, and follow-up protocols for an on-demand strategy. Our group has developed such algorithms, which are presented here.

Six-month trial of on-demand rabeprazole 10 mg maintains symptom relief in patients with non-erosive reflux disease

BACKGROUND

Compliance studies have shown that patients with reflux symptoms generally take their medication only when experiencing these symptoms.

AIM

To evaluate the efficacy of on-demand rabeprazole maintenance therapy in patients with non-erosive reflux disease.

METHODS

This multicentre, randomized, double-blind, placebo-controlled, withdrawal study compared 6 months of on-demand treatment with rabeprazole 10 mg vs. placebo. Adults with a history of reflux symptoms, a negative endoscopy, and > or = 3 days of moderate to very severe heartburn in the 7 days before enrollment (N = 535) entered 4 weeks of open-label, acute treatment with rabeprazole 10 mg once daily. Patients with complete symptom relief then entered the on-demand phase. The primary end-point was discontinuation due to lack of heartburn control during the on-demand phase.

RESULTS

Eighty-three percent (432 of 523) of patients reported complete symptom relief at the end of the acute phase. During on-demand treatment, rates of discontinuation because of inadequate heartburn control were 20% (28 of 139) for placebo vs. 6% (16 of 279) for rabeprazole (P < 0.00001). Antacid use was twofold higher in the placebo group vs. the rabeprazole group (P = 0.0009).

CONCLUSIONS

Rabeprazole 10 mg once daily is highly effective in acute symptom relief and as on-demand long-term maintenance therapy in non-erosive reflux disease patients.

Progress with novel pharmacological strategies for gastro-oesophageal reflux disease

Gastro-oesophageal reflux disease (GORD) is a chronic disorder characterised by an increased exposure of the oesophagus to intragastric contents. Currently, GORD symptoms are maintained under control with antisecretory agents, mainly gastric proton pump inhibitors (PPIs). Although impaired oesophageal motility may partly underlie the pathophysiology of GORD, the use of prokinetic agents has been found to be unsatisfactory. To date, novel pharmacological approaches for GORD are mainly related to the control of transient lower oesophageal sphincter (LOS) relaxations (TLOSRs). The majority of patients with GORD have reflux episodes during TLOSRs, which are evoked by gastric distension, mainly occurring after ingestion of a meal. Patients with reflux disease with normal peristalsis and without or with mild erosive disease could potentially benefit from anti-TLOSR therapy. This therapy might also be of value to treat some severe forms of esophagitis in combination with PPIs. GABA-B-receptor agonists are the most promising class of agents identified so far for TLOSR control. The GABA-B-receptor agonist, baclofen, is the most effective compound in inhibiting TLOSRs in humans. Since baclofen has several CNS adverse effects, novel orally available GABA-B agonists are needed for effective and well tolerated treatment of GORD. Endogenous or exogenous cholecystokinin (CCK) causes a reduction in LOS pressure, an increase in TLOSR frequency and a reduction in gastric emptying. In healthy volunteers and patients with GORD, loxiglumide, a selective CCK1-receptor antagonist, was found to reduce the rate of TLOSRs, although its effect on postprandial acid reflux may be modest. Orally effective CCK antagonists are not marketed to date. The anticholinergic agent atropine, given to healthy volunteers and patients with GORD, markedly reduced the rate of TLOSRs. Because of severe gastrointestinal (and other) adverse effects of anticholinergics, including worsening of supine acid clearance and constipation, it is unlikely that this class of drugs will have a future as anti-TLOSR agents on a routine basis. In spite of their effectiveness in reducing TLOSR rate, untoward adverse effects, such as addiction and severe constipation, currently limit the use of morphine and other opioid mu-receptor agonists. The same applies to nitric oxide synthase inhibitors, which are associated with marked gastrointestinal, cardiovascular, urinary and respiratory adverse effects. Animal studies provide promising evidence for the use of cannabinoid receptor 1 agonists, by showing potent inhibition of TLOSRs in the dog, thus opening a new route for clinical investigation in humans. A better understanding of TLOSR pathophysiology is a necessary step for the further development of novel drugs effective for anti-reflux therapy.

Cost-utility and cost-benefit analyses: how did we get here and where are we going?

Cost-utility and cost-benefit analyses are currently the only tools available for evaluating whether the cost of an intervention is a good use of resources when compared with other ways that money could be spent on health care (allocative efficiency). Cost-utility analyses assess health in terms of length and quality of life using the quality adjusted life year whilst cost-benefit analyses measure health in monetary terms. The measurement of health gain with either approach has a number of problems and the accuracy of these measures is uncertain. Cost-benefit analysis has certain advantages when measuring improvements in mild diseases such as irritable bowel disease and dyspepsia, which are common problems in gastroenterology. The results of cost-benefit analysis may provide more transparent guidance for policy makers, doctors and patients.

Clinical pharmacology of proton pump inhibitors: what the practising physician needs to know

Proton pump inhibitors (PPIs) [omeprazole, lansoprazole, pantoprazole, rabeprazole and esomeprazole] are widely utilised for the treatment of gastro-oesophageal reflux disease, as well as other acid-related disorders. All PPIs suppress gastric acid secretion by blocking the gastric acid pump, H(+)/K(+)-adenosine triphosphatase (ATPase), but the physicochemical properties of these drugs result in variations in the degree of acid suppression, as well as the speed of onset of acid inhibition. Such differences may impact on the clinical performance of PPIs, and this manuscript discusses data that may help clinicians choose between the available PPIs for specific clinical situations and indications. The characteristics of PPIs that have been developed subsequent to omeprazole offer several advantages over this prototype PPI, particularly with respect to the onset of acid suppression and reduced potential for inter-individual pharmacokinetic variation and drug interactions. Newer agents inhibit H(+)/K(+)-ATPase more rapidly than omeprazole and emerging clinical data support potential clinical benefits resulting from this pharmacological property. Although key pharmacokinetic parameters (time to maximum plasma concentration and elimination half-life) do not differ significantly among PPIs, differences in the hepatic metabolism of these drugs can produce inter-patient variability in acid suppression, in the potential for pharmacokinetic drug interactions and, quite possibly, in clinical efficacy. All PPIs undergo significant hepatic metabolism. Because there is no direct toxicity from PPIs, there is minimal risk from the administration of any of them - even to patients with significant renal or hepatic impairment. However, there are significant genetic polymorphisms for one of the cytochrome P450 (CYP) isoenzymes involved in PPI metabolism (CYP2C19), and this polymorphism has been shown to substantially increase plasma levels of omeprazole, lansoprazole and pantoprazole, but not those of rabeprazole. Hepatic metabolism is also a key determinant of the potential for a given drug to be involved in clinically significant pharmacokinetic drug interactions. Omeprazole has the highest risk for such interactions among PPIs, and rabeprazole and pantoprazole appear to have the lowest risk.Thus, whereas all PPIs have been shown to be generally effective and safely used for the treatment of acid-mediated disorders, there are chemical, pharmacodynamic and pharmacokinetic differences among these drugs that may make certain ones more, or less, suitable for treating different patient subgroups. Of course, the absolute magnitude of risk from any PPI in terms of drug-drug interactions is probably low - excepting interactions occurring as class effects related to acid suppression (e.g. increased digoxin absorption or inability to absorb ketoconazole).

The Cost of Enhanced Acid Suppression

Peptic ulcer disease (PUD), gastroesophageal reflux disease (GERD), and upper gastrointestinal bleeding are conditions that can make large demands on health care resources. Acid suppression is common therapy for these conditions. The economic implications of managing Helicobacter pylori-related PUD, GERD, and upper gastrointestinal bleeds were considered by several investigators. Economic analyses of drug regimens for PUD show that eradication is more cost effective than H2-receptor antagonist (H2RA) maintenance therapy. Although various eradication regimens have been compared, the results depend on a number of assumptions that preclude general conclusions regarding cost-effectiveness. Economic analyses related to GERD are hindered by the often chronic, relapsing nature of the disease, particularly once therapy is discontinued. Therefore, as with PUD, results of the economic analyses depend largely on initial assumptions relative to the model employed. With regard to upper gastrointestinal bleeding, proton pump inhibitors (PPIs) are potent acid suppressors that may help prevent rebleeding that was managed endoscopically. Further clinical and economic investigations of PPIs for stress ulcer prophylaxis are necessary. Cost-effectiveness studies comparing PPIs and H2RAs should focus on overall costs of managing these conditions and include economic benefits of preventing complications, and not on drug-acquisition costs alone.

The economic and quality-of-life impact of symptomatic gastroesophageal reflux disease

Gastroesophageal reflux disease (GERD) is one of the most common complaints in general medical practice. Symptoms of GERD have a high prevalence, which greatly affects health economics and patient health-related quality of life (HRQOL). The majority of patients who present with reflux symptoms lack esophageal mucosal injury and thus have symptomatic GERD. There appear to be no differences in either symptoms or HRQOL measures between patients with or without positive endoscopy. Although most pharmacoeconomic and HRQOL assessments have focused on erosive GERD patients, available data suggest that the impact of symptomatic GERD on HRQOL is significant and equivalent to that associated with erosive disease. Proton pump inhibitors (PPIs) improve HRQOL to a greater extent than either histamine(2)-receptor antagonists or prokinetics in patients with GERD, with PPI-based step-down or "on-demand" strategies yielding the most cost-effective benefit to health. Additional HRQOL and outcomes research focused on patients with symptomatic GERD, ideally using disease-specific assessment tools, is needed. Furthermore, these management strategies must be implemented in real world settings to validate their effectiveness and firmly establish claims of reduced need for diagnostic testing and decreased direct medical costs.

Symptomatic response to lansoprazole predicts abnormal acid reflux in endoscopy-negative patients with non-cardiac chest pain

AIM

To determine whether symptomatic response to lansoprazole predicts abnormal acid reflux in endoscopy-negative patients with non-cardiac chest pain.

METHODS

Patients who complained of chest pain, but had normal coronary angiography, were asked to undergo upper endoscopy. Those without gastric and oesophageal lesions were recruited for 24-h ambulatory oesophageal pH monitoring, and were randomly given lansoprazole 30 mg or placebo, both daily for 4 weeks. Chest pain symptoms were recorded before and 1 month after treatment on a locally validated questionnaire. The symptom score was calculated by multiplying the severity and frequency of the symptom, and symptom improvement was defined as > 50% reduction in symptom score.

RESULTS

Overall, 68 patients, 36 on lansoprazole and 32 on placebo, completed the trial. The symptom score was reduced significantly in both groups (P < 0.001). In the lansoprazole group, more patients with than without abnormal reflux showed symptom improvement (92% vs. 33%; odds ratio = 22; 95% confidence interval, 2.3-201.8; chi2 = 10.9; P = 0.001), giving a sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 92%, 67%, 58%, 94% and 75%, respectively. In the placebo group, the rates of symptom improvement were similar between those with and without abnormal reflux (33% vs. 35%, P = N.S.).

CONCLUSIONS

Treatment with lansoprazole is a useful test in diagnosing endoscopy-negative gastro-oesophageal reflux disease in Chinese patients with non-cardiac chest pain.

Decision making in gastroesophageal reflux disease. What are the critical issues?

This article has identified several crucial decision points in the management of GERD. Although there seems to be a strong epidemiologic association with esophageal adenocarcinoma, the clinical and economic benefits of screening endoscopy are not clear. Given the low incidence of this cancer, it is conceivable that screening programs in these patients, such as colon cancer screening and breast cancer screening, may provide a greater health benefit at a lower incremental cost. Surveillance endoscopy in BE is another contentious issue, with the surveillance interval and cost-effectiveness hinging on the cancer risk. As more precise estimates of cancer risk, accounting for publication bias, are derived, the economics of surveillance will require further evaluation. Finally, several, management strategies seem to improve outcomes for patients with uninvestigated GERD, but the incremental costs of the more effective step-down approach seem minimal. More important than the initial strategy may be the ability to implement a systematic approach to care that ensures that patients attempt step-down when symptoms are resolved and do not remain on potent therapy indefinitely when it is not necessary. The results of prospective effectiveness trials are anticipated to validate the findings of these economic analyses.

On-demand proton pump inhibitor therapy in patients with gastro-oesophageal reflux disease

On-demand therapy is an established modality in long-term therapy with histamine-2-receptor antagonists, in cases of mild non-erosive gastro-oesophageal reflux disease. In the literature, only a few studies have specifically addressed the problem of proton pump inhibitors on-demand treatment. The evidence, so far, available suggests that this might be an effective modality of long-term treatment in the majority of patients with non-erosive gastro-oesophageal reflux disease. This treatment modality appears to be the most cost-effective and the best tolerated medical regimen for gastro-oesophageal reflux disease. It also seems to be able to restore the impairment of health-related quality of life due to gastro-oesophageal reflux disease symptoms. Although the current standard of care for patients with non-erosive gastro-oesophageal reflux disease is maintenance therapy with daily administration of a proton pump inhibitor agent, on-demand therapy, with the same drug, may be a reasonable long-term choice. The ideal proton pump inhibitors for such treatment will be those with a more rapid onset of action, more profound acid inhibition, more predictable therapeutic effect and less drug-drug interactions. Newer proton pump inhibitors, like esomeprazole, the S-chiral isomer of omeprazole, are promising drugs for on-demand treatment of gastro-oesophageal reflux disease.

Refluxo laringofaringeano: estudo prospectivo correlacionando achados laringoscópicos precoces com a phmanometria de 24 horas de 2 canais

Introdução: Manifestações laríngeas do refluxo gastro-esofágico são problemas cada vez mais comuns. Estudos revelam alta associação com sensação de "globus", rouquidão crônica e com tosse crônica. Seu diagnóstico e tratamento diferem da clássica doença do refluxo gastro-esofágico. Os achados à endoscopia laríngea de hiperemia e edema de estruturas glóticas, espessamento do espaço interaritenóideo, granulomas, pólipos, edema de Reinke, estenose subglótica sugerem uma investigação diagnóstica completa através da pHmanometria de 24 horas, exame de maior sensibilidade e especificidade. Objetivo: correlacionar achados clínicos e laringoscópicos precoces sugestivos de refluxo gastro-esofágico com resultados da pHmanometria de 24 horas. Avaliar terapia medicamentosa e modificações dietéticas. Forma de estudo: Clínico prospectivo. Material e Método: pacientes adultos com queixas crônicas: tosse seca, "globus", sialorréia, disfonia, pigarro, halitose e engasgos. Foram excluídos pacientes com outras patologias de vias aéreas. Endoscopia laríngea descartava aqueles que apresentassem lesões laríngeas mais avançadas. Encaminhamento à pHmanometria e iniciado tratamento clínico. Resultados: 83,6% apresentaram refluxo patológico. Sintomas mais freqüentes: disfonia (72,5%), pigarro (60,8%), tosse (29,4%), "globus" (23,5%) e sialorréia (19,6%). Associação de sintomas: dois (67,4%); três (41,2%) e quatro (21,5%). 49 pacientes iniciaram tratamento com omeprazol (20 mg) e dieta: 83,7% cursaram com melhora dos sintomas após 6 meses. Em 95,9% dos pacientes tratados houve melhora laringoscópica. Conclusões: Houve uma correlação importante entre história clínica e endoscopia laríngea com achados à pHmanometria de 24 horas. Outros estudos poderão fortalecer a telescopia laríngea para o diagnóstico do refluxo laringofaríngeo e seu acompanhamento. É necessária abordagem multidisciplinar, além de um aumento do grau de suspeição do especialista.

Patient-centred endpoints in economic evaluations of gastro-oesophageal reflux disease

AIM

To perform a systematic review of the economic literature on gastro-oesophageal reflux disease to evaluate (a) the use of patient-centred effectiveness end-points, or (b) the use of patient-centred economic end-points, and the influence of these end-points on the outcome of the model.

METHODS

Three electronic databases (EMBASE, BIOSIS and Medline) were used, together with a manual search of meeting abstracts for relevant articles. The quality of the studies was determined by the Drummond criteria.

RESULTS

Our initial search identified 179 articles and a manual search revealed 78 abstracts and articles. A total of 47 studies (36 fully published articles and 11 abstracts) met the seven Drummond criteria for inclusion in our evaluation.

CONCLUSIONS

This systematic review demonstrates that many of the published economic evaluations available today take the perspective of the third-party payer and focus on pharmaceutical costs relevant to the third-party payer. Our study also demonstrates that there are a number of costs of illness determinations, such that pharmaceutical costs account for only a small proportion of the total costs of managing gastro-oesophageal reflux disease. Future economic analyses should consider an evaluation of the patient's desire for complete symptom relief by including cost-utility assessments or willingness to pay data.

Cost-effectiveness and cost-utility of long-term management strategies for heartburn

OBJECTIVES

To compare the expected costs and outcomes of seven alternative long-term primary care strategies for the management of patients with moderate-to-severe heartburn over a 1-year period.

METHODS

A decision-analytic model was developed to estimate costs and effects (weeks with heartburn symptoms and quality adjusted life years [QALYs]) for each strategy. Meta-analyses were used to synthesize acute treatment and maintenance studies and physician surveys to collect information on patient management. The impact of uncertainty on the base case results was assessed using probabilistic sensitivity analysis. Probability distributions were defined for key model parameters and techniques of Monte Carlo simulation were used to draw values from these distributions. Cost-effectiveness acceptability curves (CEACs) conditional on the monetary value decision makers are willing to pay for a symptom-free day or QALY were created for each strategy.

RESULTS

In the base case, no strategy was strictly dominated by any other strategy. However, two strategies (maintenance H2-receptor antagonists H2RA] and step-down proton pump inhibitor PPI]) were dominated through principles of extended dominance. The least costly and least effective strategy was intermittent H2RA, while maintenance PPI was the most costly and most effective.

CONCLUSIONS

This analysis showed that the best way of managing patients with heartburn depends on how much society is willing to pay to achieve health improvements. Based on the commonly quoted threshold of US 50,000 dollars per QALY, the optimal primary care strategy for managing patients with moderate-to-severe heartburn symptoms is to treat the symptoms with a PPI followed by maintenance therapy with an H2RA to prevent symptomatic recurrence.

Refluxo laringofaringeano: estudo prospectivo correlacionando achados laringoscópicos precoces com a pHmanometria de 24 horas de 2 canais

Introdução: Manifestações laríngeas do refluxo gastro-esofágico são problemas cada vez mais comuns. Estudos revelam alta associação com sensação de "globus", rouquidão crônica e com tosse crônica. Seu diagnóstico e tratamento diferem da clássica doença do refluxo gastro-esofágico. Os achados à endoscopia laríngea de hiperemia e edema de estruturas glóticas, espessamento do espaço interaritenóideo, granulomas, pólipos, edema de Reinke, estenose subglótica sugerem uma investigação diagnóstica completa através da pHmanometria de 24 horas, exame de maior sensibilidade e especificidade. Objetivos: correlacionar achados clínicos e laringoscópicos precoces sugestivos de refluxo gastro-esofágico com resultados da pHmanometria de 24 horas. Avaliar terapia medicamentosa e modificações dietéticas. Forma de estudo: clínico prospectivo randomizado. Método: 61 pacientes adultos com queixas crônicas: tosse seca, "globus", sialorréia, disfonia, pigarro, halitose e engasgos. Foram excluídos pacientes com outras patologias de vias aéreas. Endoscopia laríngea descartava aqueles que apresentassem lesões laríngeas mais avançadas. Encaminhamento à pHmanometria e iniciado tratamento clínico. Resultados: 83,6% apresentaram refluxo patológico. Sintomas mais freqüentes: disfonia (72,5%), pigarro (60,8%), tosse (29,4%), "globus" (23,5%) e sialorréia (19,6%). Associação de sintomas: dois (67,4%); três (41,2%) e quatro (21,5%). 49 pacientes iniciaram tratamento com omeprazol (20 mg) e dieta: 83,7% cursaram com melhora dos sintomas após 6 meses. Em 95,9% dos pacientes tratados houve melhora laringoscópica. Conclusões: Houve uma correlação importante entre história clínica e endoscopia laríngea com achados à pHmanometria de 24 horas. Outros estudos poderão fortalecer a telescopia laríngea para o diagnóstico do refluxo laringofaríngeo e seu acompanhamento. É necessária abordagem multidisciplinar, além de um aumento do grau de suspeição do especialista.

Managing gastroesophageal reflux disease

A common condition, gastroesophageal reflux disease (GERD) involves the reflux of gastric contents into the esophagus. GERD may contribute to asthma, noncardiac chest pain, and other problems. This article presents trends in GERD management, including pathophysiology, diagnosis, and treatment. The authors also explore lifestyle modifications, pharmacologic therapy, and gastroenterology referral.

A randomized, double-blind, comparative study of standard-dose rabeprazole and high-dose omeprazole in gastro-oesophageal reflux disease

BACKGROUND

Rabeprazole has a faster onset of antisecretory action than omeprazole, and it is of interest to determine whether this translates into faster symptom relief in patients with gastro-oesophageal reflux disease.

AIMS

To assess the relief from heartburn after 3 days of treatment with standard-dose rabeprazole or high-dose omeprazole (primary end-point). Secondary end-points included the decrease in score for other symptoms of gastro-oesophageal reflux disease, healing rates and quantification of antacid use.

METHODS

Patients with endoscopically confirmed erosive oesophagitis were randomized to receive 4 weeks of double-blind treatment with rabeprazole (20 mg) or omeprazole (40 mg). Patients who were not healed after 4 weeks received a further 4 weeks of treatment.

RESULTS

Two hundred and seventy-four patients were screened, 251 patients were randomized and 230 patients completed the trial. The numbers of patients with relief from heartburn on day 4 were similar in the two groups (84% for rabeprazole; 95% confidence interval, 76-90%; 83% for omeprazole; 95% confidence interval, 75-89%). There were no significant differences between the treatments in the relief from other gastro-oesophageal reflux disease symptoms or in healing rates. The number of reports of severe heartburn during the first 3 days was higher in the omeprazole group (daytime heartburn: 4.7% for rabeprazole vs. 10.3% for omeprazole, P=0.005; night-time heartburn: 4.7% for rabeprazole vs. 9.8% for omeprazole, P=0.01; statistical comparisons defined post hoc).

CONCLUSIONS

Standard-dose rabeprazole was as effective as high-dose omeprazole in relieving symptoms by day 4 of treatment and in healing oesophageal lesions, but had a faster onset of action in patients with severe heartburn. This suggests that the improved pharmacological properties of rabeprazole translate into a clinically relevant advantage.

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.

On-demand and intermittent therapy for gastro-oesophageal reflux disease: economic considerations

Since gastro-oesophageal reflux disease (GORD) is a prevalent condition characterised by frequent relapses, long-term costs of management for this disease are high. Thus, strategies to decrease resource expenditures without impairing patient quality of life are desirable. On-demand therapy (one-dose when symptoms occur) and intermittent therapy (short course of medication when symptoms occur) are attractive since pharmaceutical expenditures may be decreased, and many patients self-employ this strategy. The purpose of this paper was to examine the economic implications of on-demand or intermittent therapy for GORD. A review of selected studies evaluating medication suitable for on-demand or intermittent administration was performed. A complete search for published studies on the cost effectiveness of on-demand or intermittent therapy for GORD was conducted, and the results discussed in detail. Antacids, alginates, topically active agents, histamine(2)-receptor antagonists, and proton pump inhibitors have all demonstrable efficacy compared with placebo when administered on-demand. Proton pump inhibitors constitute the most effective pharmacological means to treat GORD. Although step-up strategies initially using less potent medication may decrease resource use, cost-effectiveness analysis illustrates that on-demand or intermittent therapy with proton pump inhibitors may be reasonable options. Further work that defines quality of life and patient preferences associated with GORD may allow for proper allocation of resources for the management of this condition.

Use of a simple symptom questionnaire to predict Barrett's esophagus in patients with symptoms of gastroesophageal reflux

OBJECTIVE

Accurately predicting Barrett's esophagus (BE) in patients with gastroesophageal reflux disease (GERD) is difficult. Using logistic regression analysis of symptom questionnaire scores we created a model to predict the presence of BE.

METHODS

We conducted a logistic regression analysis of symptom data collected prospectively on 517 GERD patients and created a prediction model based on patient gender, age, ethnicity, and symptom severity.

RESULTS

There were 337 (65%) males and 180 (35%) females, of whom 99 (19%) had Barrett's esophagus (BE). Multiple logistic regression analysis was performed to determine the predictive ability of gender, age, and ethnicity along with symptoms of heartburn, nocturnal pain, odynophagia, presence of belching, dysphagia, relief of symptoms with food, and nausea. The only significant predictors (at the 0.05 level) were male gender, heartburn, nocturnal pain, and odynophagia (all with positive effects on the presence of BE) and dysphagia (which had a negative effect). A nomogram was produced to show the effect of a given predictor on the probability of having BE in the context of the effects of the other predictors, and to estimate the probability of having BE for a given individual. The mean score (+/-SD) for the BE patients in our sample was 397.4+/-46.2 with a range of 292-530. For the patients without BE, the mean score (+/-SD) was 351.3+/-60.3 with a range of 190 - 528 (p < 0.001). If screening for BE is performed at a score of 375 or more, our model would have a specificity of 63% with a sensitivity of 77% (95% CI 61-86% given the 63% specificity).

CONCLUSIONS

By asking seven questions about symptom severity, clinicians may be able to assign a probability to the presence of BE, and thus, determine the need for endoscopy in GERD patients.

Acid-suppressive therapy use associated with antihypertensive agents

Nitrates and calcium channel blockers (CCBs) have been shown to decrease lower esophageal sphincter pressure and theoretically may precipitate or aggravate gastroesophageal reflux. Thus, the authors hypothesized that patients who receive these agents would have greater use of acid-suppressive drug use, defined as histamine2 antagonists or proton pump inhibitors. A retrospective cohort design was used to assess the use of acid-suppressive drug use in hypertensive patients with respect to both nitrates and antihypertensive therapy. Of 15,662 treated hypertensive patients, 20% received acid-suppressive therapy. An increased use of acid-suppressive therapy was associated with nitrate (odds ratio [OR] = 1.71), CCB (OR = 1.46), and alpha 1 antagonist (OR = 1.32) treatment, which appeared to be additive when patients received two or more of the agents. Within the class of CCBs, there was no significant difference among the individual agents. As the clinical and economic burden may be substantial, further study is warranted.

Quality of life measurement clarifies the cost-effectiveness of Helicobacter pylori eradication in peptic ulcer disease and uninvestigated dyspepsia

OBJECTIVES

Previous economic studies of Helicobacter pylori eradication in dyspepsia and peptic ulcer disease have not measured quality of life using utilities (preference probabilities), which are needed to compare the cost-effectiveness of such treatment to other health care interventions. The goals of this study were to measure quality of life in patients with dyspepsia or peptic ulcer and apply these measurements to published models of disease management to determine cost-effectiveness in dollars per quality-adjusted life year (QALY) gained.

METHODS

Utilities for dyspepsia and peptic ulcer disease were measured in adult patients (n = 73) on chronic acid suppression for peptic ulcer or ulcer-like dyspepsia. Median utility values were applied to the results of published cost-effectiveness analyses and a previously validated dyspepsia model. Cost-utility ratios for early H. pylori eradication in uninvestigated dyspepsia and peptic ulcer disease were then computed.

RESULTS

The total disutility, or lost quality of life, for an ulcer was 0.11 QALY, of which 0.09 QALY was attributed to dyspeptic symptoms. After these results were incorporated into published studies, cost-utility ratios for ulcer treatment varied from $3,100 to $12,500 per QALY gained, whereas estimates for uninvestigated dyspepsia management ranged from $26,800 to $59,400 per QALY. Sensitivity analyses indicated a range of $1,300 to $27,300 per QALY for management of duodenal ulcer and $15,000 to $129,700 per QALY for dyspepsia.

CONCLUSIONS

Strategies that emphasize early H. pylori eradication were cost-effective for patients with peptic ulcer and possibly cost-effective for patients with uninvestigated dyspepsia, relative to other medical interventions. Dyspeptic symptoms cause significant disutility that should be incorporated in future cost-effectiveness analyses of treatment strategies.

Proton pump inhibitors in the treatment of gastro-oesophageal reflux disease

Gastro-oesophageal reflux disease (GERD) is the most common peptic acid disease in the western world and is the commonest indication for acid suppression therapy. Major advances have been made over the past 30 years in the understanding of lower oesophageal sphincter function and the mechanism of acid secretion. Developments in surgical and pharmacological therapy have paralleled these advances. Pharmacotherapy for GERD has evolved from antacids to H2-receptor antagonists (H2RAs) to prokinetics to proton pump inhibitors (PPIs). The H2RAs, while modestly effective in symptom relief and healing of GERD, are limited by pharmacological tolerance. The prokinetics (metoclopramide and cisapride) are limited by low efficacy, pharmacological tolerance and toxicity. The PPIs have emerged as the most effective therapy for symptom relief, healing and long-term maintenance. They have also proved to be remarkably safe and cost-effective in long-term therapy. This review evaluates the pharmacology, efficacy, tolerability, safety and cost-effectiveness of the four currently available PPIs, lansoprazole, omeprazole, pantoprazole and rabeprazole, in the treatment of GERD.