Pre-Diabetes

Patients at High Risk of Type 2 Diabetes

Prediabetes is characterised by the presence of blood glucose levels that are higher than normal but not yet high enough to be classed as diabetes. If undiagnosed or untreated, prediabetes can develop into Type 2 Diabetes (T2D).

For this reason, prediabetes is often described as the grey area between normal blood sugar and diabetic levels and is a risk factor for cardiovascular disease and future Type 2 Diabetes.

Diagnosing Prediabetes

Prediabetes can be diagnosed using a single HbA1c (HbA1c 42-47 mmol/mol)

A fasting glucose may also be used, and Glucose Tolerance Tests can provide initial indications.

Prediabetes includes impaired glucose tolerance and impaired fasting glycaemia.

So although Impaired fasting glucose/prediabetes/impaired glucose tolerance are all distinct entities based on which diagnostic test you use, their clinical management is sufficiently similar that, in primary care, we can consider them to be one condition.

These are the definitions that should be used for practice coding and referral purposes. These definitions are shown in Table 1 in the Resources and Links section.

Who to refer:

Refer patients with Prediabetes (High Risk of Diabetes) to the Let’s Prevent Diabetes (LPD) programme.

Patients can be given a copy of this information leaflet about LPD: Lets Prevent Diabetes.pdf

Patients that have had previous Gestational Diabetes (GDM) are at increased risk of future T2D, so those with GDM are automatically offered LPD post-partum as part of the Lothian GDM Pathway. There may be people with a history of previous GDM some years ago, direct referrals to LPD are welcomed at any time from this cohort.

Patients with PCOS are often high risk. Consider risk stratification and testing.

Further information on programmes, links to healthy lifestyle resources and contact details can be found on the NHS Lothian Adult Weight Management and Type 2 Diabetes Service web page.

Who not to refer to LPD:

Patients already diagnosed with T2D. The DESMOND programme and My Desmond digital health pathway is designed to provide early intervention and education for those newly diagnosed.
Patients with only a low/moderate risk of Diabetes (See details in Primary Care Management section)
Patients who do not have a diagnosis of prediabetes but may require weight management support.

How to refer:

Referrals are accepted from all health care professionals via sci-gateway or by letter, email or referral form to Weight Management Mailbox.

Please click here to visit the Adult Weight Management RefHelp page for more information.

Patients are able to self refer to Let’s Prevent Diabetes programme using this form Adult Weight management Referral form.pdf

Primary care teams play a significant role in the identification of patients who are at High risk of diabetes (Prediabetes) but also those at moderate risk of developing diabetes.

At risk groups include those known to be at increased risk of T2D, due to the risk factors below.

Risk Factors:

Age: Over 40 years old (white Caucasian) or over 25 years old (African-Caribbean, Black African or South Asian)
Family history: 2-6 times more likely to develop T2D if a parent, brother, sister or child has diabetes
Ethnicity: T2D is 2-4 times more likely in people of South Asian descent and African-Caribbean or Black African descent*
Overweight: BMI over 25 (white Caucasian) or over 23 (African Caribbean, Black African or South Asian)
Waist circumference:
- Women: 31.5 (80-cm) inches or over
- Men: 35 (90 cm) inches in south Asian men 37 (94cm) inches in white or black men

High blood pressure or previous heart attack or stroke
Polycystic ovary syndrome
Previous gestational diabetes**
Severe mental health problems including those prescribed Clozapine and Olanzapine which are known to induce weight gain and increase risk of T2D.

The more risk factors present, the more risk of developing Type 2 Diabetes.

* Minority Ethnic Health Inclusion Services’ (MEHIS) Pathways support LPD provision specifically within MEHIS communities

**Patients with previous gestational diabetes should be offered a fasting glucose check between 6 and 12 weeks after giving birth, or HbA1c test after 13 weeks. These patients are now offered structured education at diagnosis and throughout pregnancy with a specialist Dietitian. Post-partum, patients are offered a referral to the Let’s Prevent Diabetes programme, specifically for those with previous GDM. NICE guidelines recommend carrying out annual HbA1c checks for people with previous gestational diabetes.

Patients may wish to help and calculate their score online; this requires weight, height and waist circumference.

1. Calculate and code RISK score:

This can be calculated via the Diabetes UK Know Your Risk Tool, which requires patients to measure height, weight and waist circumference.

NICE guidelines encourage keeping an up to date register of RISK scores, along with introducing a recall system to invite those at risk of Type 2 Diabetes in for regular review. This is also an opportunity to support patients to manage lifestyle changes and encourage goal setting.

2. Manage RISK score:

The summary diagram is as follows. Please view interactive NICE guidelines for further details.

NICE Guidelines: Managing Risk of Type 2 Diabetes

3. Lifestyle changes

Lifestyle changes with the aim of managing excess weight and increasing exercise are pivotal to the prevention of diabetes, but consider all the pillars of health

Dietary patterns – A Healthy Balanced Diet. There is some evidence for Mediterranean, DASH diet, whole foods plant based and low carbohydrate diets but the most important changes are ones patients are motivated to stick with. For more information about the individual programmes for weight management click here.
Physical activity – Get moving with counterweight is the Tier 2 programme provided by local health coaches throughout Lothian (https://services.nhslothian.scot/AWMT2D/Pages/getmovingwithcounterweight.aspx). Physical activity support is also available as part of NHS Lothian’s specialist Tier 3 weight management service (https://services.nhslothian.scot/AWMT2D/Pages/specialistweightmanagementsupport.aspx).
Healthy sleep (https://www.wellbeinglothian.scot/area/better-sleep/)
Stress management (https://www.wellbeinglothian.scot/area/dealing-with-stress/)
Discuss harmful substance avoidance (alcohol/smoking)

4. Monitoring of Prediabetes

Prediabetes is monitored with an Annual HbA1c, unless symptoms develop prior to this. Those that have attended LPD, making changes and attempting to impact HbA1c levels should be offered a HbA1c test 3 months post LPD completion.

Advise patients to look out for the following:

Polyuria
Polydipsia
Change in eyesight
Weight loss
Lethargy
Thrush oral/genital

Table 1.

Coding Prediabetes and Diabetes (SNOMED) table:

Category	Fasting plasma glucose		HbA1c		2h glucose post OGTT
	Value (mmol/l)	N	Value(mmol/moll)	N	Value(mmol/l)	n
Normal glycaemia	<5.5		<42		<7.8
Original pre-diabetes	6.1-6.9		42-47		7.8-11.0
pre-diabetes	5.5-6.9		42-47		7.8-11.1
Impaired glucose tolerance IGT					7.8-11.1
Impaired Fasting Glycaemia (IFG)	5.5-6.9		42-47
Diabetes	>=7.0		>=48		>=11.1
At risk of Type 2 Diabetes (T2D)	At risk of T2D is defined as being at moderate or high risk of T2D via the Diabetes UK Know Your Risk Tool.
High risk of Type 2 Diabetes (T2D)	High risk T2D is defined as those with previous or current gestational diabetes, those with polycystic ovary syndrome or those with prediabetes.