Beware of heartburn -New Straits Times Tuesday, 01/09/2009-

Beware of heartburn

If you are lucky enough to be going on holiday this month, you will probably be eating and drinking a little more than is good for you.

And if you are one of the five million or so people in the UK prone to heartburn then that over indulgence is likely to come at a price. But there can be much more to heartburn than a bout of dyspepsia after too much Rioja.

An innocent symptom in most people, heartburn can sometimes indicate a more sinister underlying problem: a condition called Barrett's oesophagus, where repeated exposure to stomach acid causes changes in the lining of the oesophagus (gullet) that can lead to cancer.

The changes are named after the surgeon Norman Barrett, who first noted them 50 years ago. The condition follows the rule of tens: one in ten of the British population has problems with heartburn, one in ten of them will develop Barrett's, of whom one in ten will go on to develop cancer of the oesophagus.

The underlying abnormality that is responsible for heartburn is a malfunction of the valve where the gullet joins the stomach - a problem that is particularly common in the obese and in people over the age of 35. The stomach has a layer of slime that protects it against its own digestive juices, which are as strong as battery acid. But the oesophagus has no such defence mechanism and if acid travels back through the defective valve (reflux) then it burns the delicate gullet lining, causing the characteristic symptom of heartburn.

It is possible to have reflux without any symptoms, but the classic story is of a middle-aged man or woman who gets discomfort behind his or her breast bone, often worse after meals or when lying flat in bed. Other common complaints include a tendency to belch, an irritating dry cough, and increased awareness of cold, hot or strong alcoholic drinks.

Barrett's oesophagus is probably a defence mechanism. The changes in the tissue mirror many of the characteristics of the lining of the stomach, and are thought to be the gullet's attempt to protect itself. While the new lining may be more resistant to acid, it is also much more likely to turn cancerous - a process that typically takes ten or more years.

Cancer of the oesophagus is common and nasty, and Barrett's oesophagus is the biggest risk factor for the most common form. There are just under 8,000 cases of oesophageal cancer diagnosed in the UK every year, 70 per cent of which will cause death within a year of diagnosis. Because the transition from Barrett's to cancer is slow, it is possible to monitor people with the condition and to catch them at a stage before the cancer has time to develop.

The problem facing doctors is how to identify the 10 per cent of the millions of heartburn sufferers who have Barrett's. Currently, the only way to diagnose it is to do an endoscopy and directly visualise and biopsy suspicious looking areas. But it is not practical to endoscope everyone.

The Medical Research Council Cancer Cell Unit at Addenbrooke's Hospital in Cambridge may have come up with the answer. Known as the sponge test, it involves swallowing a capsule attached to a piece of string. After a few minutes the capsule dissolves to release a small sponge which can then be withdrawn and tested for the molecular features associated with Barrett's.

The sponge test is still being trialled but early results look promising. If a test turns out be positive, endoscopy would be the next step to confirm the diagnosis. If he or she does have Barrett's , the patient will be called back for regular endoscopies to check for more suspicious changes: every two to three years for stable Barrett's, down to every three to four months for someone with more worrying histology.

The fortunate majority of people who test negative may be able to reduce their risk of going on to develop Barrett's through a combination of self help measures (avoiding coffee, smoking and losing weight) and regular medication with drugs such as omeprazole to decrease acidity in the stomach.- The Times