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l REVIEW Gastro-oesophageal reflux disease (GORD) Karen van Rensburg, BPharm Abstract Gastro-oesophageal reflux disease is a common gastrointestinal disease. Patients who suffer from this condition report a broad spectrum of symptoms. The symptom most commonly associated with gastrooesophageal disease is heartburn (usually experienced behind the breastbone) occurring at least two to three times per week. It usually occurs 30–60 minutes after meals, resolving spontaneously or with the use of antacids. The goal of the treatment of GORD is to provide adequate symptomatic relief, to heal oesophagitis if it is present and to prevent complications from developing. Empirical treatment is often implemented based on an adequate history and presence of the most common symptoms. Introduction Gastro-oesophageal reflux disease (GORD) has become one of the most common gastrointestinal diseases affecting between 10–40% of the population in Western countries.1,2 Patients who suffer from this condition report a broad spectrum of symptoms, making it difficult to reach a consensus as to what exactly constitutes typical reflux disease. The American Journal of Gastroenterology published a definition in 2002 as agreed upon at a Brazilian consensus conference: “GORD is a chronic disorder related to the retrograde flow of gastro-duodenal contents into the oesophagus and/or adjacent organs, resulting in a spectrum of symptoms, with or without tissue damage”. This definition recognises the chronic character of the disease, and acknowledges that the refluxate can be gastric and duodenal in origin, with important implications for the treatment of the disease.3 gastro-oesophageal barrier, and at present, only fundoplication (a surgical procedure to treat gastro-oesophageal reflux disease and hiatus hernia) is known to correct the functionality of the sphincter.4,5 Abnormal gastric emptying could also contribute to GORD by increasing intragastric pressure. Gastroprokinetic agents such as metoclopramide can improve gastric emptying and should be considered.3,4 Hiatus hernias occur commonly and are not always associated with any symptoms. But, in patients with GORD, they are associated with higher amounts of acid reflux and delayed oesophageal acid clearance leading to oesophagitis. Hiatus hernias are associated with recurrence of failure of medical therapy for GORD.3,4 Aetiology Signs and symptoms Various factors contribute to the development of GORD. Under healthy conditions, a very effective barrier exists between the stomach and the oesophagus. Firstly, peristalsis and salivary production promote oesophageal clearance. And secondly, a valve system exists between the oesophagus and the stomach to prevent reflux. This valve comprises of the lower oesophageal sphincter (LOS), the diaphragm, the His angle, the Gugaroff valve and the phrenoesophageal membrane.3 The symptom most commonly associated with GORD is heartburn (usually experienced behind the breastbone) occurring at least two to three times per week. It usually occurs 30–60 minutes after meals, resolving spontaneously or with the use of antacids. The pain associated with heartburn can often be confused with angina pectoris.1,4,6 Defective peristalsis can be associated with GORD as it is the main determinant of oesophageal clearance of the refluxate. In 2001, Diener reported that between 40–50% of patients with GORD suffer from abnormal peristalsis.3 This causes the refluxate to move through the oesophagus at a slower pace, being in contact with the mucosa for a longer period of time causing mucosal damage, often resulting in a dry and irritating cough.4 GORD is also associated with a mechanically incompetent LOS.3,5 An incompetent LOS is a permanent defect of the 34 SAPJNovDec10pp34-37.indd 34 Dysphagia (difficulty in swallowing) due to erosive oesophagitis and regurgitation (the perception of flow of refluxed gastric content into the mouth) are also commonly present.1 More recently, various “atypical” symptoms are also being recognised with increasing frequency, such as asthma, chronic coughing, sore throat and chronic laryngitis.4 Complications that can occur include oesophagitis, oesophageal ulcers, peptic oesophageal stricture and Barrett’s metaplasia. SA Pharmaceutical Journal – November/December 2010 12/3/2010 10:28:07 AM REVIEW l Diagnosis GORD is usually diagnosed based upon the symptoms and the response to treatment. Obtaining a careful history can often point to the correct diagnosis. Performing tests may not always be necessary, as patients with reflux who do not suffer from complications, can often be treated simply by making lifestyle changes or with the use of medications. If the diagnosis is unclear or if complications are present, specific testing might be required. Oesophagoscopy Oesophagoscopy is usually the initial evaluation of suspected GORD and a biopsy can be performed at the same time if required. In South Africa, the Los Angeles classification system is used to grade the severity of oesophagitis (see Table I). Two thirds of patients have a normal endoscopy and are termed non-erosive reflux disease.1,7 These patients should however be treated in a similar fashion to those with erosive oesophagitis as the other symptoms in these patients are just as difficult to control. Ambulatory oesophageal pH monitoring1,4,7 This diagnostic guideline helps to confirm GORD in patients with persistent symptoms without evidence of mucosal damage, especially when a trial of acid suppressing medication has failed. Ambulatory pH monitoring can be done via a transnasally placed catheter or a wireless capsule shaped device that is affixed to the distal oesophageal mucosa. Monitoring the pH this way is useful and indicated: •• To document abnormal oesophageal acid exposure if a patient with a normal endoscopy but is being considered for antireflux surgery. •• To monitor patients who have been unresponsive to treatment with proton pump inhibitors. Complications Barrett’s oesophagus This condition occurs when the normal squamous cells that line the lower oesophagus are replaced by intestinal cells. This is the result of repeated damage to the lining of the oesophagus after a long period of time. These patients often do not experiTable I: Los Angeles classification of endoscopic grading1 Grade Description A One or more mucosal breaks no longer than 5 mm, none of which extends between the tops of the mucosal folds. B One or more mucosal breaks more than 5 mm long, none of which extends between the tops of two mucosal folds. C Mucosal breaks that extend between the tops of two or more mucosal folds, but which involve less than 75% of oesophageal circumference. D Mucosal breaks which involve at least 75% of oesophageal circumference. SA Pharmaceutical Journal – November/December 2010 SAPJNovDec10pp34-37.indd 35 ence any symptoms different to that from GORD, other than dysphagia due to impaired motility. Barrett’s oesophagus can develop into oesophageal adenocarcinoma.1,4 Stricture The oesophagus can be scarred due to acid damage, which may lead to subsequent narrowing (stricture), most commonly at the gastroesophageal junction. Ironically, this stricture can cause a reduction in heartburn as the stricture can act as a barrier to reflux.4 Treatment The goal of treatment is to provide adequate symptomatic relief, to heal oesophagitis if it is present and to prevent complications from developing. Empirical treatment is often implemented based on an adequate history and presence of the most common symptoms. When patients do not respond to empirical treatment, further examinations may need to be conducted. The severity of the disease is often an indicator of the type of treatment required. Lifestyle changes Many patients with mild symptoms may benefit from lifestyle modifications, although on its own, lifestyle changes are not likely to completely control symptoms in the majority of patients. Patients should be educated about the factors that can precipitate and aggravate reflux. Various studies have encouraged elevation of the head of the bed, decreased fat intake, smoking cessation and weight loss to reduce symptoms of GORD.1,7 Patients should be advised to avoid acidic food (e.g. citrus fruits, tomato products, spicy foods) and foods that can cause the LOS to relax (e.g. chocolates, peppermint and alcohol). Acid suppression through use of medication There are five main classes of drugs that have been evaluated for treatment of GORD: •• Surface agents •• Antacids •• Prokinetics •• Histamine-2 receptor antagonists •• Proton pump inhibitors Surface agents4,8 Surface agents create a barrier that helps prevent injury to mucosal surfaces of the stomach and oesophagus. The two agents that have been evaluated in the treatment of GORD are sodium alginate and sucralfate. Products containing sodium alginate (e.g. Gaviscon®) form a surface gel that creates a physical barrier against regurgitation of gastric contents and protects the oesophageal mucosa. Sucralfate (Ulsanic®) is a sucrose hydrogen sulphate aluminium complex. It acts as a mucosal protective agent and assists in ulcer healing without altering gastric acid secretion. It stimulates angiogenesis by binding to injured tissue, delivering growth factor and reducing the access that acid has to the mucosa. 35 12/3/2010 10:28:07 AM l REVIEW Antacids Most antacids are readily available over the counter. Although antacids can give rapid relief of pain, their duration of action is usually relatively short (2 hours). Many over-the-counter antacids contain a combination of Al(OH)3 and Mg(OH)2, e.g. Maalox®, Mucaine®. These products have the advantage that they do not affect bowel function as much as the individual components on their own would have. The drugs in this class include omeprazole, lansoprazole, rabeprazole, pantoprazole, and esomeprazole. (See Table II.) Surgery3,4,7,8 Surgical fundoplication, although controversial, provides good to excellent relief of symptoms in over 85% of appropriately selected patients and is more effective than medical management for the treatment of GORD in the short to medium term. Surgical treatment should only be considered for: a) Otherwise healthy patients with extraoesophageal manifestations of reflux, Prokinetics4,8 Color profile: Generic CMYK printer profile Promotility drugs like metoclopromide and cisapride can Default help screen b) for patients with severe reflux disease who are not willing to Composite take medication every day because of the cost, inconvenience to reduce reflux by increasing the pressure of the LOS thereby or potential risks thereof, c) patients with enhancing oesophageal peristalsis and erosive disease who are intolerant of or gastric emptying. Because of various resistant to PPIs. side-effects associated with these drugs, they are often used only as a last resort in patients who have failed antisecretory therConclusion It's the apy (proton pump inhibitors and histamine It is clear that the pathophysiology of GORD type 2 receptor antagonists) and for pais multifactorial, creating disagreement as shell that tients who are healthy (no evidence or acid to what typically constitutes typical GORD. makes reflux or other disease on evaluation) for It is important to remember that not all pawhom quality of life is adversely affected tients require diagnostic evaluation such as safer. by recurrent vomiting or regurgitation. endoscopy, and should only be performed on patients presenting with complications Cisapride has been known to prolong QT or patients who have not responded to an Safety-Coated intervals, leading to cardiac arrhythmias empirical trial of PPI therapy. 81mg and metoclopramide may cause neuropsyThe ORIGINAL low dose aspirin chiatric side-effects due to its mechanism Unfortunately, most patients do not respond for optimum cardio-protection of action as a dopamine antagonist. to lifestyle advice and require further Each tablet contains Aspirin 81mg. Reg.No.: 29/2.7/0767 Pharmafrica (Pty) Ltd, 33 Hulbert Road, New Centre, Johannesburg 2001 therapy. H2RAs and PPIs are better than Under licence from Goldshield Pharmaceuticals Ltd. U.K. Histamine type 2 receptor antagonists placebo in oesophagitis. Most patients need Patients with uncomplicated GORD with reflux symptoms that long-term treatment because the disease usually relapses. 55X75MM 23 September occur several times a week can be treated empirically with2008 H2 10:02:46 AM PPIs are superior to histamine type 2 receptor antagonists receptor antagonists (H2RAs). The H2RAs inhibit acid secre(H2RAs) in relieving symptoms and healing oesophagitis. tion by blocking histamine H2 receptors on the parietal cell. Surgery is still considered to be relatively controversial although carefully selected patients treated by experienced surgeons The two main H2RAs used in South Africa include cimetidine have resulted in excellent outcomes.r (Lenamet®) and ranitidine (Zantac®, Ranihexal®). R R pH For reflux oesophagitis, cimetidine should be taken at a dose of 400 mg four times a day with meals and at bedtime for up to 12 weeks. The indicated dose for ranitidine is 150 mg twice a day OR 300 mg at bedtime for eight to twelve weeks. It may be increased to 150 mg four times a day for up to twelve weeks in moderate to severe GORD. Studies have shown that H2RAs are superior to placebo for healing oesophagitis and improving symptoms. Their benefit is greatest for patients with mild oesophagitis, but unfortunately tolerance can eventually develop, limiting efficacy for long-term management.8 Proton pump inhibitors Proton pump inhibitors (PPIs) block acid secretion by irreversibly binding to and inhibiting the hydrogen-potassium ATPase pump that resides on the luminal surface of the parietal cell membrane. 36 SAPJNovDec10pp34-37.indd 36 References 1. Kahrilas PJ. Clinical Manifestations and diagnosis of gastroesophageal reflux in adults. Up to date. Version 18.2 [Cited 2010 August 30] 2. Liakakos T, Karamanolis G, Patapis P, Misiakos EP. Gastroesophageal Reflux Disease: Medical or surgical treatment. Gastroeneterology Research and Practice. 2009:Article ID 371580. 3. Patti MG. Gatroesophageal reflux disease: From pathophysiology to treatment. World Journal of Gastroenterology. 2010:16(30):3745-3748 4. Tierney LM, McPhee SJ, Papadakis MA, editors. Current Medical Diagnosis and Treatment 2003. 42nd edition. New York: McGraw-Hill. 2003. 5. Berkow R, editor. The Merck manual of diagnosis and therapy. 16th edition. New Jersey: Merck Research Laboratories; 1992. 6. Kahrilas PJ. Patient information: Gastroesophageal reflux disease in adults. Up to date. Version 17.3 [Cited 2010 Jan 18]. 7. DeVault KR, Castell DO. Updated guidelines for the diagnosis and treatment of gastroesophageal reflux disease. American Journal of Gastroenterology. 200;100:190-200. 8. Winter HS. Management of gastroesophageal reflux disease in children and adolescents. Up to date Version 18.1 [Cited Aug 30] 9. Gibbon CJ, editor. South African Medicines Formulary. 6th edition. Western Cape: Creda Communications. 2003. 10. Snyman JR, editor. Monthly index of medical specialities. Volume 49 number 9. September 2009 SA Pharmaceutical Journal – November/December 2010 12/3/2010 10:28:12 AM REVIEW l Table II: Proton pump inhibitors available in South Africa4,5,9,10 Drug Dose/Indications* Drug Interactions Schedule Side effects Omeprazole Losec® Recurrent reflux oesophagitis: 20 mg daily for 4–8 weeks Reflux oesophagitis long-term treatment: 10 mg daily, increase to 20–40 mg if needed Can prolong elimination of diazepam, warfarin, phenytoin Increases bioavailability of digoxin S4 Skin rashes, gastrointestinal reactions, insomnia, vertigo, malaise, muscle weakness, blurred vision Esomeprazole Nexiam® Erosive reflux oesophagitis: 40 mg once daily for 4–8 weeks GORD: 20 mg once daily for 4 weeks Prevention of relapse: 20 mg once daily Patients on NSAIDs: 20–40 mg once daily Prevention of gastric and duodenal ulcers associated with NSAID therapy in patients at risk: 20 mg or 40 mg once daily. IV: indicated where oral therapy is not appropriate and for the shortest possible time Erosive reflux oesophagitis: 40 mg once daily for 4 weeks Long-term management to prevent relapse: 20 mg once daily Severe reflux: 20 mg once daily Maintenance of haemostasis and prevention of rebleeding of gastric or duodenal ulcers: 80 mg administered as bolus infusion over 30 minutes followed by a continuous intravenous infusion of 8 mg/hr given over 3 days Possible increase/decrease in absorption of drugs influenced by stomach acid, ketoconazole, itraconazole, prolonged diazepam clearance, increased phenytoin plasma concentrations, slight elevation of warfarin trough plasma concentration S4 Headache, dizziness, blurred vision, abdominal pain, skin reactions, dry mouth Lansoprazole Lanzor® Oesophagitis due to gastrooesophageal reflux: 30 mg daily for 4 weeks depending on endoscopic results Dyspepsia: 15 mg daily for 2–4 weeks Maintenance for prevention of gastro-oesophageal reflux: 15 mg daily Lanzor HB®/Lansoloc OTC®: 15 mg once daily as short-term relief of heartburn and acid dyspepsia Bioavailability reduced by sucralfate, affects absorption of drugs sensitive to acid environment S4 Lansoloc OTC® S2 Lanzor HB® S2 Pantoprazole Pantoloc® Gastric ulcer and reflux oesophagitis: 40 mg daily for 4–8 weeks Mild GORD: 20 mg daily for 4–8 weeks GORD relapse prevention: 20 mg daily, increase to 40 mg in case of relapse then reduce to 20 mg daily after healing Lesions caused by NSAIDs: 20 mg once daily Possible changes in absorption of pH-dependant medications e.g. ketoconazole S4 GI disturbances, allergic reactions, headaches, dizziness, depression, jaundice Rabeprazole Pariet® Erosive or ulcerative GORD: Oral, 20 mg once daily 4–8 weeks. Maintenance to prevent relapse: 10–20 mg once daily for up to twelve months Ketoconazole, itraconazole, increased digoxin levels S4 Headache, GI disturbances, allergic reactions, cough, leg cramps, dizziness Abdominal pain, allergic reactions, halitosis, malaise, arthralgia, Steven-Johnson * These products all have additional indications, only those relevant to this article have been highlighted SA Pharmaceutical Journal – November/December 2010 SAPJNovDec10pp34-37.indd 37 37 12/3/2010 10:28:13 AM