QDiabetes

Risk of developing type 2 diabetes. Open the calculator

QDiabetes® - identifying patients at high risk of type 2 diabetes

What is the difference between QDiabetes®-2018 and earlier versions of QDiabetes®?

We have developed and validated updated equations to predict the 10-year risk of type 2 diabetes in men and women aged 25 to 84 years. The equations incorporate established predictor variables as well as new risk factors associated with an increased risk of type 2 diabetes.

The new equations include the risk factors used in QDiabetes®-2017 together with

  • learning disability
  • schizophrenia or bipolar affective disorder
  • atypical antipsychotics
  • statins
  • gestational diabetes
  • polycystic ovary syndrome,

and

  • fasting blood glucose; and
  • HbA1c,

where these are known.

These new risk factors help ensure more accurate estimation of the level of risk in those with these new risk factors, improving information for individual patients and surveillance strategies.

For individuals, the presence of these new risk factors could substantially increase their absolute risks of diabetes. These changes in absolute risk could push individuals over a risk threshold, which may then result in different clinical management.

As QDiabetes®-2018 has equations for use both with and without fasting blood glucose and HbA1c tests, it can be used to support the two-step approach to the identification of patients at high risk of diabetes as recommended by NICE guidance and the NHS Health Checks programme. Use of these parameters, either singly or together, identify a subset of those affected and enables us to more accurately estimate their risk.

This calculator gives a score only when at least one blood test is entered: a fasting blood glucose, an HbA1c, or both. When a fasting blood glucose is entered, the score uses it; when only an HbA1c is entered, the score uses the HbA1c.

What is QDiabetes®?

  • QDiabetes® is a validated tool which predicts the absolute risk of developing type 2 diabetes in the next 10 years.
  • It is useful as there is good evidence that diabetes can be prevented with targeted interventions such as weight loss, exercise and lifestyle changes
  • It is available online here at qdiabetes.org, and can be integrated into GP computer systems.

What factors are needed to calculate a QDiabetes® score?

  • As well as the factors listed above in the discussion on QDiabetes®-2018, the following factors are needed: age, sex; ethnicity; deprivation score; smoking status; family history of diabetes; history of cardiovascular disease; hypertension on treatment; regular steroid use; body mass index

Which patients can you use it in?

  • QDiabetes® can be used in any patient aged 25-84 without existing diagnosis of type 1 or type 2 diabetes

What are the special features of QDiabetes® compared with other risk tools?

  • QDiabetes® is based entirely on variables which the patient is likely to know or information which is recorded in the GP practice computer.
  • It has been developed by academics and doctors working in the NHS using data from the QResearch database (qresearch.org) which includes more than 700 general practices across the UK. The very large and representative population means that the results will generalise well to primary care patients.
  • The original algorithm was formally validated on two separate populations of patients1,2 - one from EMIS practices and one from Vision practices. The results show it accurately predicts the level of risk (which is called calibration) and also distinguishes well between those at risk (i.e. discrimination). One of the validations was conducted by a fully independent team from Oxford University. This is the 'gold standard' for validation of risk prediction tools1.
  • The underlying algorithm which calculates the QDiabetes® score has been fully published so that it transparent and open to scrutiny.
  • It has been designed to integrate well with QRISK®2 - many of the questions overlap and so it is possible to combine QDiabetes® and QRISK®2 into a combined vascular risk assessment.
  • QDiabetes® is updated regularly to take account of changing incidence of diabetes, increasing prevalence of diabetes and improvements to data quality.
  • QDiabetes® has been recommended in the recent NICE guidelines on the identification of patients at risk of diabetes published in July 2012.

How do I use the tool?

You can also use the tool here or at qintervention.org. This combines QRISK®2 with QDiabetes® to give a combined vascular risk. You can also use the 'what if's to demonstrate to patients how their risk would change with interventions such as weight loss.

QDiabetes® is available for all GP system suppliers to integrate as with QRISK®2. It has already been integrated into EMIS Web both as

  1. a calculator tool which can be used to risk assess patients within the consultation using data already recorded in the clinical system. This is very efficient and will store the result into the clinical record so that it can be used for analyses and reporting in the practice, and
  2. a batch processing tool which allows you to risk score every patient and generate a list of high risk patients for further assessment and intervention.

What constitutes high risk?

There is no absolute answer to this but as a rule of thumb, 10% of the population will have a 10%+ risk of developing diabetes over the next 10 years.

Some practices are risk scoring their populations and then ordering the list so that those at highest risk are at the top of the list. You can then call in the top X number of patients for further assessment depending on practice workload.

References

  1. Collins GS, Altman DG. External validation of the QDScore for predicting the 10-year risk of developing Type 2 diabetes. Diabetic Medicine 2011;28:599-607.
  2. Hippisley-Cox J, Coupland C, Robson J, Sheikh A, Brindle P. Predicting risk of type 2 diabetes in England and Wales: prospective derivation and validation of QDScore. BMJ 2009;338:b880-.

Further information

For the 2016 annual update, we have updated the underlying deprivation data.

QDiabetes® Risk Thresholds (2015)

In order to inform thresholds for the NHS Health checks programme, we undertook an analysis of the sensitivity, specificity and observed risk for incident type 2 diabetes using the latest annual update of the QDiabetes® score deriived from the latest version of the QResearch database.

The results are here: