High Risk Screening for Diabetes
Evidence shows that systematic population-screening for diabetes is not cost-effective but that targeted screening of those at high risk is.
Patients with “prediabetes” including Impaired Glucose Tolerance, Impaired Fasting Glycaemia, a past history of Gestational Diabetes or ‘stress’ hyperglycaemia are at particularly high risk of developing Type 2 Diabetes and should be recalled annually for a fasting venous (plasma) glucose measurement, with the results interpreted and acted on as per the Diagnostic Algorithm.
Other patient groups at high risk of diabetes should be screened opportunistically, preferably by fasting venous glucose measurement (see below). These include:
- Subjects from non-Caucasian ethnic groups
- Those with a family history of Type 2 Diabetes
- Those who are obese, in particular with central adiposity (waist 31.5 inches or over for women and 37 inches or over for men)
- Women with polycystic ovarian syndrome
Both Scottish and NICE guidance highlight the benefits of detecting Type 2 diabetes earlier. Treatments for “prediabetes” reduce risk of progression to diabetes, however there is not yet evidence to show any reduction in morbidity or mortality.
SIGN are currently developing an update to their existing guideline Management of Diabetes (SIGN 116) in relation to the Prevention of Type 2 diabetes.
Regardless of risk, lifestyle advice can help all in the short-term. In those at highest risk, metformin can reduce the progression to Type 2 Diabetes (NNT 4.6 to prevent 1 case of diabetes over 3 years)
Population Risk Assessment and Screening for Diabetes
NICE recommends that GPs and other health professionals and community practitioners in health and community venues, including pharmacists, voluntary organisations and employers should implement a two-stage strategy to identify people at high risk of Type 2 diabetes and those with undiagnosed Type 2 diabetes. First, a risk assessment should be offered using validated self-assessment or validated web-based tools. Second, where appropriate, a blood test should be offered to confirm whether people have Type 2 diabetes or are at high risk.
The Diabetes UK Risk Assessment Tool, helps patients quantify risk. This is also available on Vision: Calculators/Other/Diabetes Risk (see page 3). A paper version of this tool and the Patient Results Letter recommended for use in Tayside can be viewed and downloaded from the Handbook here: (Validated Risk Score & Risk Score Letter)
Vision Diabetes Risk Calculator:
Low Risk
For those patients found to be low risk or increased risk (up to 15%) on the risk assessment tool, lifestyle advice only is required and there is no need for regular blood tests.
Moderate Risk
For those patients found to be moderate risk on the risk assessment tool a further fasting blood glucose test should be carried out and acted on as per the Diagnostic Algorithm. Repeating every 3 years is recommended (this will be the majority of people with hypertension only for example) [not annually]
Typing ‘hypertension review, last glucose 2018’ on the test request will keep track of when glucose testing should next be offered.
High Risk
For those patients found to be high risk on the risk assessment tool a further fasting blood glucose test should be carried out and acted on as per the Diagnostic Algorithm. A testing interval should be agreed with the patient up to annually.
The use and interpretation of random blood glucose measurements for ‘screening’
Urinalysis or capillary blood glucose meter/ test strip analyses are not considered to be accurate screening tools. Abnormal findings using these methods should always be followed up by repeating with a venous (plasma) screening sample.
Interventions
There is good evidence that healthcare professional support and ‘brief interventions’ to encourage exercise and dietary modification in patients at moderate and high risk of diabetes can be effective in producing weight loss and thus in preventing the development of diabetes.
Resources available for healthcare professionals
- The MAP of Health Behaviour Change is a module for health and social care professionals whose role involves helping people to make positive health and lifestyle related changes. It can be found within TURAS.
- Small Talk Big Difference
Resources available for people at risk of Type 2 diabetes
- The Type 2 Diabetes Prevention course is aimed at anyone that is at risk of developing Type 2 diabetes. This course aims to give you the information you need to know about what Type 2 diabetes is and how you can reduce your risk of developing it.
https://elearning.mydiabetesmyway.scot.nhs.uk/courses/type-2-diabetes-prevention/
- Information on about local, national and online resources to support people with lifestyle changes e.g. NHS Inform Weight Management Programme, walking groups
http://www.diabetes-healthnet.ac.uk/Default.aspx?pageid=301
As part of Implementing the Framework for Type 2 Diabetes Prevention, Early Detection and Early Intervention pathways and resources are being developed to support people identified as being at risk of Type 2 diabetes. Information on these will be incorporated into this guidance and pathways once available.