INTRODUCTION

The identification more than 80 years ago of insulin, a hormone which is secreted in the pancreas, and its introduction in purified form for treating diabetes mellitus, was one of the most dramatic medical advances of the 20th century.

It was soon recognised that, in some people with diabetes, the pancreas is unable to produce insulin (type 1 diabetes), while in others (type 2 diabetes), the amount produced is inadequate, or their bodies fail to respond sufficiently to the insulin produced. For many thousands of people who would previously have faced a premature death, daily injections of insulin came to mean not only survival, but also the chance to live a relatively normal life. Today, insulin injections still remain a mainstay of treatment for many people with diabetes.

By the 1950s it had become clear that, while insulin treatment greatly improves life expectancy, serious complications such as kidney or eye disease, nerve damage, amputation, heart attacks and strokes can develop later in the course of diabetes and severely curtail survival or impair quality of life. These complications are seen in both forms of the disease.

In the United Kingdom today, diabetes is estimated to have been diagnosed in as many as 2 million people. In 2003 the Health Survey for England found that 4.3 per cent of men and 3.4 per cent of women had been diagnosed with diabetes, about 90 per cent of them type 2 diabetes. In both men and women, the prevalence of diabetes increases rapidly with age.

In addition, between 765,000 and 1,000,000 people are thought to be affected by type 2 diabetes that has so far not been diagnosed. In its early stages, type 2 diabetes may be associated with few or mild clinical symptoms and hence may not be promptly recognised.

Diabetes imposes an enormous burden on the individual and on the medical system. Complications of diabetes are expensive to treat, impair quality of life and shorten life expectancy. As a consequence, people with diabetes require more frequent, intensive and prolonged treatment, often hospital-based, than those without the disease.

Hospital statistics for England in 2003-2004 show that people with diabetes accounted for over 68,000 finished consultant episodes (consultations with specialists which may involve more than one visit) and required 368,000 bed days of in-patient care.

In the first decade of the 21st century, diabetes has become a major public health problem in many countries, including those in the developing world. In the UK, spending on diabetes is estimated to make up 9 per cent of total NHS expenditure already, and this is projected to grow by 20-30 per cent by the year 2040.

As a result, there are two clear priorities for the coming years:

• Preventing the development of new cases of type 2 diabetes.
• Managing both forms of diabetes as well and cost-effectively as possible, in order to prevent or delay the development of complications.

In the past decade, diabetes has become the focus of increasingly intense research, both into the mechanisms underlying the disease as well as its complications and clinical management. As a result, the outlook is potentially more positive than ever before.

This booklet summarises some key insights from this research, outlines the main options for treating diabetes today, and identifies some of the new medicines that are currently under development. However, it is not a treatment guide, but an introduction for those directly affected and their families and carers, to help understand diabetes and the therapies available to treat it.