Allergies

Introduction

What is allergy?

Allergy results from an over-reaction of the immune system to a substance that is normally harmless. Many different parts of the body may be affected.

Allergy in modern society

The number of people in the United Kingdom with allergies has increased threefold over the last 20 years and continues to rise. One in three of the UK population now suffers from a medical problem caused by or associated with allergy, a total of 18 million people; 7 million of these are thought to be so severely affected that they require specialist care. It is predicted that a similar increase in the prevalence of allergy will be seen in developing countries as they become more westernised. Researchers in India have reported a 50 per cent increase in asthma diagnoses compared with five years ago.

Many of the factors thought to be responsible for the increase in allergic diseases are related to our western lifestyle. These include our unnaturally refined diet, the early introduction of certain foods to the infant diet, our style of housing, the popularity of indoor furry pets, the increased exposure to chemicals that may cause allergies, the tendency for smaller households with fewer people and our exposure to tobacco smoke.

Many of these factors are especially potent in small children, so it is this age group that is most affected by the rising incidence of allergy.

Allergic disease is the reason for six per cent of all appointments in general practice, and takes up £900 million of the primary care budget. A report by the Royal College of Physicians has highlighted that allergic disease in the UK has become not just more common, but also more severe and more complex.

However, there are not enough specialist allergy centres in the UK, and currently there is only one consultant allergist for every two million people, whereas in other specialties – for example, cardiology – there is one consultant for every 100,000 people. Most GPs have had no clinical training in allergy.

The Royal College of Physicians is trying to address this problem and more allergy specialists are in training. However, in their 2010 report, the Royal College reported that there has been little progress in the past three years and allergy services in the UK are inadequate. As a result of this, patient education is vital. The more that you can learn about your allergies, the better equipped you will be to manage the problems presented by them in everyday life.

Allergic diseases are chronic in nature, that is, they are persistent, recurring over many months or years. People with allergies don’t necessarily look ill, but they are not perfectly well either. Having an allergy problem can interfere with your sleep, making you tired, and may affect your appetite and decrease your ability to concentrate.

All this adds up to make you feel less than 100 per cent, and in the long term both your family life and your time at work or school may suffer.

As the symptoms of allergic disease often increase slowly over time, you may not realise how big an impact they are having on your life. Low-level symptoms such as coughing, sneezing or sniffing are accepted as ‘normal’, and you may end up with lower expectations of what you can manage.

The role of allergies in common diseases

The most common diseases in which allergy plays a part are asthma, hay fever (also called allergic rhinitis), allergies affecting the skin (including eczema and contact dermatitis) and food allergy.

Allergy and asthma

Asthma causes episodes of wheezing, coughing and shortness of breath that can be triggered by a range of things, including the common cold, exercise, contact with certain animals, a high pollen count and exposure to house-dust mite and tobacco smoke.

It is a frequent problem in children, affecting as many as one in seven school-aged children. Asthma is slightly less common in adults – affecting about one in ten – but is still a major cause of ill-health. Although many studies have confirmed that asthma is becoming more common, yet we still do not know enough about why.

Allergy and hay fever

Hay fever may be a seasonal condition, causing symptoms in late spring and summer, or may be perennial, causing problems all year round. Its symptoms might not sound serious – a runny or blocked nose, watery itchy eyes and sneezing – but they make the lives of hay fever sufferers a misery, and interfere with work, study and sleep.

The exact number of people with hay fever is difficult to judge, but it is thought that as many as 20 per cent of the British population have hay fever at some stage in their lives.

Skin allergy

Skin allergies may take several different forms. Probably the best known is eczema, but other problems such as contact dermatitis, urticaria (hives) and angio-oedema (facial swelling) may also result from an allergy. Although skin allergy can affect both sexes, more women in particular are developing new skin allergies. This may be because the average woman uses five different cosmetic and skin care products on her skin every day, and these are likely to contain around 100 different chemicals, any one of which could cause an allergic reaction.

Food allergy

Food allergy is becoming more common, affecting six to eight per cent of children and around two per cent of adults. It is also becoming more serious, with hospital admissions in the UK rising 500 per cent since 1990. Not all unpleasant reactions to food are caused by allergy, as there are a number of other reasons why a food might disagree with you, including food intolerance, a sensitivity to food and food aversion.

Misdiagnosis of allergy

The problem of misdiagnosis is not confined to food allergy. Some people diagnose themselves as having allergic diseases without having this confirmed by a doctor. In addition, some alternative practitioners use tests that have not been scientifically assessed and these tests may incorrectly diagnose allergy.

The careful and accurate diagnosis of allergic problems is important for two reasons. First, sufferers may make major changes in their diet or in their lifestyle, in the belief that they have an allergic disease, and these changes may interfere with the quality of their lives if their problem is not the result of allergy for no good reason and involve considerable expense. Second, labelling their condition incorrectly prevents them from discovering the true reason for their problem and then finding the best treatment for it.

This book explains what happens in the body when an allergy occurs and how to discover whether or not allergy is the cause of your problem. It also describes the different ways of diagnosing allergy and discusses the different treatments available. Finally, useful information about living with allergies is given.

If you have an allergy-related condition, this book should help you to find your way through the maze of diagnosis and treatment. No book can be a substitute for consultation with a doctor, but by making you better informed and well prepared, this book will help you to be more in control of your allergic problems and so to manage them better.

KEY POINTS

• Allergy is becoming more common

• One in three people in the UK is affected by allergy

• Allergy is often misdiagnosed

• There are too few specialist allergy clinics in the UK