Understanding Irritable Bowel Syndrome

Introduction

What is irritable bowel syndrome?

Irritable bowel syndrome (IBS) is one of the most common gastrointestinal disorders, but it is puzzling for those who have it and for the doctors who treat it. Unlike disorders such as stomach ulcers or arthritis, there is no laboratory test, X­ray, scan or endoscopic investigation that can show whether or not you have IBS.

There is no clear­cut cure for the disorder. However, various kinds of treatment can relieve the symptoms and, with the right kind of support from your doctor, you can learn to live with it.

IBS is a syndrome, a collection of symptoms with similar features that occur together in a pattern that your doctor can recognise. In typical cases, there is rarely any doubt about the diagnosis, although you may have symptoms in any part of your gastrointestinal tract, which stretches from the oesophagus (gullet) to the rectum.

What are the main symptoms?

The term ‘irritable’ is used to describe the reaction of the muscles in the intestine, which respond to stress by abnormal contractions. These may result in various combinations of the three main symptoms: pain diarrhoea constipation. These symptoms are often worrying. However, if you have been told that you have IBS, you can take some comfort from the information that the disorder does not increase your chance of developing long­term serious conditions such as cancer or ulcerative colitis.

Also, there is no evidence that people with IBS have a shorter life expectancy.

What will I find in this book?

The first five chapters of this book describe the structure and working of the gastrointestinal tract. They explain the symptoms of IBS and how it is recognised. They also cover what is known about its causes and how common it is in people from different ethnic groups in countries around the world.

Later chapters deal with common symptoms such as constipation and diarrhoea. They explain how these apparently opposite problems can be part of the same syndrome. These chapters also describe the various approaches to treatment that may be tried and how these can help. There is also practical advice on self­help measures that you may try. The final chapters of the book discuss how people with IBS can learn to live with the disorder, and get support from a sympathetic doctor. The more that you understand about IBS and the reasons for your symptoms, the better you will be able to cope with them. We hope that this book will help you to do just that.

How common is IBS?

Irritable bowel syndrome affects around one in five adults in the industrialised countries. Even more people have at least one of its symptoms. A study in the USA found that, in one year, as many as 70 per cent of the general population had problems associated with abnormal bowel function, such as abdominal pain, constipation or diarrhoea. Three­quarters of people with symptoms of IBS do not consult a doctor, and yet as many as half the people seen in a hospital outpatient clinic for gastrointestinal disorders have it as the cause of their problems. Evidence suggests that half the people with IBS seen in clinics also have symptoms of depression or anxiety. In the UK, around eight million people have IBS. On average, each of them has 17 days off work a year, at an annual cost to the country of £500 million. Average work days missed in the USA per year were 14.8, compared with 8.7 in those without symptoms of IBS. Indeed, IBS ranks close to the common cold as a leading cause for absenteeism from work as a result of illness. Symptoms of IBS are equally common in men and women, but women consult their doctors about these symptoms more often than men. About half of those with IBS develop symptoms before the age of 35; 40 per cent of people with the condition are aged 35 to 50 years.

There is a tendency for symptoms to occur less often as you get older, but some people do experience them for the first time later in life. Doctors tend to be more cautious about diagnosing IBS in elderly people. They will usually do so only after excluding other diseases of the gut.

KEY POINTS

• IBS is a syndrome, not a disease, affecting about 20 per cent of adults in industrialised countries.

• Doctors see twice as many women as men with the condition

• IBS has a major social impact, leading to frequent days off work and restriction of social activities