Media playback is unsupported on your device Media caption Stephen Richardson had to have his leg amputated because of type 2 diabetes

Diabetes prescriptions are costing the NHS in England more than £1 billion a year, according to figures from NHS Digital.

The total cost of the prescriptions has risen significantly - by more than £422 million - in the last 10 years.

Almost one in 20 prescriptions written by GPs are now for diabetes treatment.

The biggest increases are seen in treatments for type 2 diabetes, which affects around 90% of diabetes patients.

Robin Hewings, head of policy at the charity Diabetes UK, said the figures reflect a dramatic rise in the incidence of diabetes.

"The number of people diagnosed with diabetes has doubled in the last 20 years, and it is responsible for 26,000 early deaths per year alongside serious complications such as blindness, amputation or stroke.

"This data shows that diabetes prescribing costs £1bn, but it is estimated that the total cost to the NHS is over £10bn a year, so the real price we have to pay for diabetes is not medications, but the devastating and expensive complications."

Mr Hewings pointed out that drug costs have not risen significantly during this period, and that the increase in prescribing costs is largely a result of the rise in prevalence of type 2 diabetes.

The rise in diabetes

There are now over three million people in England with a diagnosis of diabetes. The number has doubled over the last two decades and there are nearly 100,000 diagnoses per year.

92% of recorded diagnoses of diabetes relate to type 2 diabetes. Type 2 diabetes, unlike type 1, is closely linked to lifestyle factors and is preventable through lifestyle change.

Almost seven out of 10 men are overweight or obese (66.8%) and almost six out of 10 women are overweight or obese (57.8%) in England.

Source: NHS England

Type 2 diabetes is caused by the body not producing enough insulin, or by the body's cells not reacting to the insulin that is present, resulting in high blood sugar.

It may be controlled by diet, or by antidiabetic drugs or insulin, or both.

Type 2 is caused by a variety of factors, some of which are out of people's control, but more than 80 percent is caused by obesity or being overweight.

In overweight and obese people, type 2 diabetes can be prevented and reversed by losing weight.

The NHS England figures also include the cost of devices used by people with diabetes to monitor their condition.

Nearly £477 million was spent on antidiabetic drugs in 2017-18. Over the same year, around £350 million was spent on insulin, and £181 million on diagnostic and monitoring devices.

Professor Jonathan Valabhji, national clinical director for diabetes and obesity at NHS England, said: "Thanks to better diagnosis and treatment, the NHS is caring for more people than ever before with diabetes, and this new data highlights the urgent need to prevent type 2 diabetes from developing in the first place.

"The NHS Diabetes Prevention Programme has now reached over a quarter of a million people at high risk of type 2 diabetes."

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