The diabetes explosion

Millions of people are at risk from diabetes and we need to examine our lifestyles and those of our children to prevent it becoming an epidemic, says Dr Lesley Hickin.

In the UK, 1.4 million people suffer from diabetes and at least another million are estimated to have it without knowing. The cost of treating diabetes and related conditions is soaring and is set to use up a fifth of the entire NHS budget by the year 2010.

The reasons for the increase include an ageing population (Type 2 diabetes is more common among older people), growing obesity among all age groups and lack of exercise. There are also worrying signs that overweight children who don't exercise are risking diabetes in later life. Three out of five adults in the UK are considered overweight or obese, and one in four children.

What is diabetes?
Diseases involving the chemical reactions going on in your body are called metabolic disorders. Diabetes (or diabetes mellitus, sugar diabetes) is the most common of these. Normally carbohydrate-containing foods are broken down into glucose (sugar) to be absorbed from the bowel into the bloodstream. Glucose in the blood is then delivered to cells in all the tissues of the body, where it is broken down to give us energy by chemical reactions.

Insulin, a hormone produced by a gland called the pancreas, situated behind the stomach, helps glucose enter cells. Levels are increased in response to a rise in the blood glucose level, and levels of insulin go down when blood glucose levels fall, for example during exercise. In this way the blood glucose level is kept within a narrow range. Insulin also enables carbohydrate stored in muscles and the liver to be converted to glucose when necessary.

In diabetes the amount of glucose in the body rises too high because of insufficient insulin or resistance to the action of insulin in the tissues. The cells have to find an alternative source of energy, particularly stored fat, leading to a build-up of toxic waste products in the body. Glucose accumulates in the blood and spills out into the urine, drawing extra water with it. All these processes can lead to the symptoms of diabetes detailed below.

Many people think of diabetes simply as a disorder of glucose and insulin, but it would be more realistic to think of it as a complicated metabolic disorder of glucose and blood lipids (fats in the blood including cholesterol), high blood pressure and disease of blood vessels.

The two types

Type 1 diabetes develops when there is a severe lack of insulin in the body because most or all of the cells in the pancreas that produce insulin are destroyed. This type of diabetes often appears suddenly in childhood, though it can occur up to the late 30s. The cells in the pancreas are destroyed by the body's immune system for an as yet unknown reason. About 350,000 people in the UK have this type of diabetes.

  • Treatment consists of lifelong administration of insulin, exercise and a healthy diet. At the present time insulin is given daily by injections, using various types of insulin. New genetically produced insulin as close in structure to human insulin as possible is available, said to give better control of blood glucose levels over a long period of time. Insulin can also be given continuously using a pump. Research is being carried out into insulin administered nasally, and transplants of pancreatic islet cells to produce insulin in the diabetic patient's body.

  • Type 2 diabetes develops when the insulin produced does not work properly at the tissue level (known as insulin resistance). Reduced amounts of insulin are also produced and this becomes more of a problem the longer the person is affected.It is increasing across all age groups, including children and young people. Doctors are warning that the number of sufferers of Type 2 diabetes is set to rise to three million in the next decade.

  • The condition develops slowly over a number of years. It is estimated that at the time of diagnosis many people will have had the problem for 10 years or more, and have sometimes developed severe complications by that time. Predisposition to Type 2 diabetes including a family history of the disease, being of Asian or Afro-Caribbean origin, being very overweight or having had a baby weighing 4kg (8lbs 13oz) or over. About one in three affected people have a close relative with Type 2 diabetes.

  • Treatment: when the disease is first diagnosed the mainstay of treatment is a lifelong healthy diet and regular exercise. In time, if the condition is out of control, it will be necessary to treat with tablets, and when a person has had Type 2 diabetes for 10-15 years there is a good chance that insulin injections will also be required.

    Symptoms
    Type 1 diabetes develops acutely and the symptoms tend to be more severe. They include tiredness, weight loss, excessive thirst and hunger, passing large amounts of urine, poor sleep (from getting up to pass urine at night) and blurred vision. In some people the onset is more serious and severe (diabetic ketoacidosis) and they require hospital admission to stabilise the body fluids. Symptoms suggesting this include vomiting, abdominal pain, drowsiness, headache, confusion, deep breathing and the scent of acetone (like pear drops or nail polish remover) on the breath.

    Type 2 diabetes has a more insidious onset with similar symptoms as above except that Type 2 diabetics do not develop ketoacidosis. Recurrent infections such as vaginal thrush, boils or cystitis may indicate raised blood sugar levels, since the immune system is impaired under these conditions.

    Complications
    The complications of diabetes are similar in Types 1 and 2. The longer you have had diabetes the more likely you are to develop complications. They are related to the effect that a persistently high blood glucose level has on the delicate membrane lining of the arteries. Microscopic damage to this membrane (called the vascular endothelium) causes cholesterol and other substances to be deposited, narrowing the calibre of the artery. This reduces the amount of oxygen supplied to the tissues and can causes long term damage to the eyes, kidneys, nerves, and the blood vessels supplying the heart and brain. The blood supply to the feet can also be affected, causing reduced blood flow.

    All these changes lead to the vastly increased risk that diabetics have of developing problems with their eyesight, angina and heart attacks, strokes, kidney failure, foot ulcers, gangrene and leg amputations.

    All diabetics have an increased risk of high blood pressure and high blood lipids (cholesterol and triglycerides) so these need treating vigorously as well as blood sugar control being optimal.

    How can complications be prevented?
    We know from research over a number of years that the better controlled the diabetes, the lower the risk of developing complications. This means regular check-ups (three or four a year) either with a GP, specialist nurse or hospital diabetic clinic.

    Maintaining a healthy diet and exercising regularly are essential, as are taking care of feet and having regular eye check-ups. Diabetics should all have access to a dietician, chiropodist and retinal screening facility staffed by people with special training and experience in dealing with diabetes.

    Diabetics more than most people should not smoke because of the increased risk of developing vascular disease.

    Type 1 diabetics need to monitor their own blood glucose levels to adjust the amount of insulin they require and ensure the blood levels are correct. More and more people with Type 2 diabetes are also self-monitoring to ensure that their treatment is working well.

    Find out more

    Diabetes UK
    10 Queen Anne Street
    London W1G 9LH
    Tel: 020 7323 1531
    Fax: 020 7637 3644
    Email: info@diabetes.org.uk
    Visit: www.diabetes.org.uk