Two new risk prediction tools can identify patients with diabetes who are at high risk of complications such as blindness and amputation, according to UK researchers.
The tools are based on variables that patients are likely to know or that are routinely recorded in general practice computer systems, said the study authors in the British Medical Journal.
“To our knowledge, these are the first tools for predicting the 10-year risk of both blindness and amputation”
Diabetic eye disease is now the second most common cause of blindness in people of working age in the UK, while more than 7,000 diabetes related amputations take place annually in England.
But methods of identifying those at greatest risk are lacking, said Professor Julia Hippisley-Cox and Professor Carol Coupland from the University of Nottingham.
They set out to develop and validate a new risk prediction algorithm to predict the absolute risk of developing these complications over a 10-year period in men and women with diabetes.
Using data derived from electronic patient records, their analysis was based on around 455,000 people with diabetes aged 25-84 years from 763 general practices in England.
Mathematical models were then used to calculate separate risk equations for the 10-year risk of blindness and amputation.
Data from a further 611 practices were used to validate the two models, which performed well, explaining around 41% and 32% of the variation in time to amputation and blindness, respectively.
The authors also developed a web-based calculator so clinicians could enter their patients’ data, and patients can enter their own data, to determine the 10-year risk of these complications.
“To our knowledge, these are the first tools for predicting the 10-year risk of both blindness and amputation, two of the complications that most concern patients with diabetes and affect quality of life,” said the study authors.
They acknowledged some study weaknesses, including the lack of formal adjudication of diagnoses and the potential for bias due to missing data.
Nevertheless, they said 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 reflecting their own values and choices”.
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 added.
- The web calculator to calculate the absolute risk of complications among patients with diabetes is available online