Two new risk prediction tools can identify patients with diabetes who are at high risk of blindness and amputation, a study in the BMJ reports.

The algorithms calculate the absolute risk of developing complications over a 10 year period by taking into account individual risk factors.

Developed by Professor Julia Hippisley-Cox and Professor Carol Coupland at the University of Nottingham in the UK clinicians and patients can enter their details into a web based calculator to find out their risk.

More accurate individualised information on the risk of complications “may help patients to make more informed decisions about the balance of risks and benefits of treatment options,” the authors say.

For clinicians more accurate methods for stratifying patients according to their absolute risk of complications “could enable screening programmes to be tailored to an individual’s level of risk and support the more rational use of scarce resources,” they concluded.

An accompanying editorial said the risk tools needed to be tested in actual practice – and to test their impact outside the UK, particularly in countries with the highest prevalence of diabetes.

The tools were developed using data from 455,000 people with diabetes aged 25-84 years from 763 general practices in England.

Individual risk factors that could influence the results, such as ethnicity, smoking, body mass index, blood pressure and cholesterol levels were taken into account.

Mathematical models were then used to calculate separate risk equations for the 10 year risk of blindness and amputation. Data from a further 611 general practices were used to validate the two models.

The web calculator is available at http://qdiabetes.org/amputation-blindness/index.php