Should patients with Barrett's oesophagus be kept under surveillance? The case against

Barrett's oesophagus, or columnar metaplasia of the oesophagus, is a known risk factor for adenocarcinoma of the oesophagus. Barrett's oesophagus is thought to be the result of longstanding gastro-oesophageal reflux disease, a very common diagnosis in the United States and other western countries. Because Barrett's oesophagus is a transition state between a common complaint and a devastating illness, endoscopic screening and surveillance strategies are commonly employed. However, neither screening nor surveillance strategies have been proven to reduce mortality from oesophageal adenocarcinoma. We address the multifaceted case against surveillance for oesophageal adenocarcinoma. The overall incidence of oesophageal adenocarcinoma is very low, especially compared to other cancers where surveillance is used. The pace of progression from Barrett's to adenocarcinoma is not known. There is a lack of evidence supporting surveillance programmes. There are drawbacks to endoscopic surveillance for dysplasia and adenocarcinoma in patients with established Barrett's oesophagus that include sampling error, inconsistent pathologic interpretation of biopsies, and cost. Taken individually or together, these limitations make a strong case against surveillance endoscopy in Barrett's oesophagus.     

Are screening and surveillance for Barrett's oesophagus really worthwhile?

Oesophageal adenocarcinoma has a low incidence and still remains an uncommon cancer; however, it has been on the rise over the past 20 years. Barrett's oesophagus, a complication of gastro-oesophageal reflux disease, is the only known precursor of this adenocarcinoma. It can often be asymptomatic and probably goes undiagnosed in the majority of the population. There are no direct data supporting the practice of screening for Barrett's oesophagus and oesophageal adenocarcinoma among the general population or even in patients with chronic reflux symptoms. However, many argue that the detection of neoplasms at a curable state in a high risk population can perhaps justify screening endoscopy. No prospective, controlled trials have been conducted to support the effectiveness of surveillance, but some indirect evidence does exist. The cost effectiveness of surveillance programmes needs to be further assessed in prospective studies. Ultimately, the use of better tools to diagnose Barrett's oesophagus and dysplasia and the identification of high risk groups for progression to oesophageal adenocarcinoma could potentially make screening and surveillance a cost effective practice.     

Should patients with venous thromboembolism be screened for thrombophilia?

In the mid-19th century, Virchow identified hypercoagulability as part of the triad leading to venous thrombosis, but the specific causes of hypercoagulability remained a mystery for another century. The first specific cause to be identified was antithrombin III deficiency. Many other causes of thrombophilia, both genetic and acquired, have been discovered since then. The 2 most common genetic causes of thrombophilia are the Leiden mutation of factor V and the G20210A mutation of prothrombin. The most common acquired cause is antiphospholipid syndrome. These factors increase the relative risk of an initial episode of venous thromboembolism (VTE) by a factor of 2 to 10, but the actual risk remains relatively modest. Therefore, thrombophilia screening to prevent initial episodes of VTE is not indicated, except possibly in women with a family history of idiopathic VTE who are considering oral contraceptive therapy. Some physicians screen for thrombophilia to aid decision making concerning the duration of anticoagulant therapy. However, several studies have demonstrated that, with the exception of antiphospholipid syndrome, thrombophilia does not significantly increase the risk of recurrent VTE. On the other hand, idiopathic VTE significantly increases the risk of recurrence in patients with or without thrombophilia.     

Should ECG criteria be modified for geriatric patients?

When an elderly patient has an abnormal electrocardiogram but no other objective evidence of heart disease, the physician may question whether the ECG is really a reliable index of heart disease in old people or whether aging has some influence on which findings are normal and which are abnormal. The study reported here plus data gathered from an extensive review of the literature indicate the ECG criteria do not have to be changed for geriatric patients. Regardless of age, the prognosis of a specific abnormality remains that of the underlying disease. With age, both heart disease and abnormal electrocardiograms increase in incidence--in a parallel fashion. Specific abnormalities that increase in frequency are first-degree atrioventricular block, bundle-branch block, ST-T wave changes, premature systoles, left anterior hemiblock, left ventricular hypertrophy, and atrial fibrillation. Those that correlate strongly with heart disease are atrial fibrillation, left bundle-branch block, and nonspecific intraventicular condution defect.     

Should all patients with metabolic syndrome be treated with statins?

The metabolic syndrome is a constellation of cardiovascular risk factors that include atherogenic dyslipidemia, elevated blood pressure, abdominal/truncal obesity, and glucose intolerance. Current National Cholesterol Education Program (NCEP) recommendations for specific treatment of the metabolic syndrome are centered on therapeutic lifestyle changes. A recent publication from the NCEP Adult Treatment Panel III suggests pharmacologic intervention for parameters of metabolic syndrome, including dyslipidemia, hypertension, and hyperglycemia, to prevent cardiovascular disease, based on risk category. This review looks at the clinical trial evidence to support the use of statins in metabolic syndrome.     

Should hyperhomocysteinemia be treated in patients with atherosclerotic disease?

Numerous retrospective and prospective observational studies support an association between elevated homocysteine and increased risk for myocardial infarction, stroke, and peripheral vascular disease. Although folic acid therapy substantially reduces homocysteine levels, recent large, randomized controlled trials failed to translate folic acid-induced homocysteine reduction into clinical benefit for the secondary prevention of cardiovascular events. These studies are compelling and have generated some newfound skepticism regarding a clinical role for folic acid therapy. Because these intervention trials have been limited to patients with mild hyperhomocysteinemia, the results of the trials imply that folic acid therapy may be best suited for individuals with more robustly elevated homocysteine levels. Furthermore, the potential benefit of folic acid therapy for primary prevention in individuals at low-or intermediate-risk for atherothrombotic disease has not been studied to date. Thus, at this time, folic acid therapy for borderline or mild hyperhomocysteinemia is not recommended. However, the role of folic acid therapy in patients with intermediate or severe hyperhomocysteinemia, or for primary prevention of cardiovascular diseases, remains unresolved.     

Barrett's oesophagus: better left alone?

The risk of oesophageal adenocarcinoma in patients with Barrett's oesophagus is overrated in most publications, including meta-analyses. The upper limit of the overall risk is currently estimated at 0.5 per 100 patients per year. This means that one cancer may occur out of 200 patients followed for one year. Furthermore, a large fraction of patients with Barrett's oesophagus have a precarious health status, either from advanced age or from a chronic severe disease. Management is based upon a careful index endoscopy; accordingly, patients positive for dysplasia must be strictly observed or treated. Endoscopic surveillance protocols aiming at early detection of neoplasia--and treatment--in patients without dysplasia are unjustified in most cases. On the other hand, a minority of male patients--providing a good performance status--should enter into surveillance protocols when high-risk factors such as a long history of reflux symptoms and smoking habits are present.     

Should cisapride be avoided in patients with diabetic gastroparesis?

The gastrointestinal motility stimulants, cisapride and erythromycin, have been used in the management of diabetic gastroparesis. However, drug interactions may result in prolongation of the electrocardiographic QT interval with the risk of ventricular arrhythmias. These drugs should, therefore, not be used in combination. We report two cases that illustrate inappropriate use of these agents. Moreover, patients with recurrent severe hypoglycemia or renal impairment may be at increased risk from cisapride-related cardiotoxicity. Thus, even as monotherapy, cisapride may pose dangers for high-risk diabetic patients.