- Approximately 15% of the population are at high risk of developing diabetes
- Self-assessment tools or routine practice data should be used to identify individuals at high risk of developing diabetes
- Brief advice on the risk of developing diabetes and the benefits of a healthy lifestyle should be offered to people with a low or intermediate risk of diabetes
- A blood test (fasting glucose or glycated haemoglobin) should be offered to those with a high risk score
- A structured intensive lifestyle programme should be offered to people whose fasting glucose is 5.5–6.9 mmol/l or glycated haemoglobin is 42–47 mmol/mol (6.0%–6.4%)
- Metformin or orlistat should be considered for individuals who are unable to make the necessary lifestyle changes or who continue to progress towards diabetes despite such interventions
- Clear communication is needed between primary care and community providers to ensure appropriate follow up of those at high risk
- Reassessment of risk of diabetes is needed every 1–3 years depending on the baseline risk.
Diabetes has reached epidemic proportions in the UK, affecting approximately 3 million people, of whom around 90% have type 2 diabetes.1 There is no sign that the increase in prevalence over the last two decades is slowing down and it is estimated that as a result of changing population demographics, the number of people affected by diabetes will reach 5 million within the next 15 years.1
Diabetes results in a huge personal and financial burden—it is associated with the development of both microvascular complications, affecting the eye, kidney, and nerves, and macrovascular complications; on average, people with diabetes die 5–10 years earlier than the general population.2 Currently the NHS spends £9.8 billion per year on diabetes care, most of which covers the cost of treating complications; the cost is projected to rise to £16.8 billion by 2035, equivalent to 17% of the entire NHS budget.3 Given the huge morbidity and mortality associated with the condition and its financial costs, there is a strong imperative to implement measures to prevent diabetes.
Since the beginning of the millennium, a number of randomised controlled trials from Finland, USA, and Asia have demonstrated beyond doubt that lifestyle modification can prevent, or at least delay, the onset of type 2 diabetes.4–6 These trials, however, used interventions of an intensity that could never be replicated in everyday clinical practice. More recent trials have adapted the principles of lifestyle diabetes prevention into more practical solutions.7,8 Alongside these intervention studies, our understanding of the risk of diabetes has advanced and several tools are now available that allow a reasonably accurate assessment of diabetes risk in clinical practice. This combination of better identification and affordable interventions has made prevention of diabetes a realistic and cost-effective proposition.9
Need for guidance
In July 2012, NICE published Public Health (PH) guidance 38 to improve the identification and management of adults at high risk of type 2 diabetes.10 In particular, the guidance addresses the management of individuals with impaired glucose regulation (either impaired fasting glucose or glucose intolerance) who comprise 15% of the adult population, and are 5–15 times more likely to develop type 2 diabetes than those in the general population who have normal glucose values (see Figure 1).10–13
At present, the identification and management of adults at high risk of type 2 diabetes occurs on an ad hoc basis and there may be missed opportunities where simple interventions could be provided to reduce the incidence of diabetes. By adopting a broad approach across a variety of healthcare and community settings, the NICE guidance should lead to better care for these individuals at high risk. These recommendations complement previously published NICE Ph25 guidance, which was targeted at reducing the risk of diabetes across the whole population.14
Figure 1: Identifying and managing risk of type 2 diabetes10
BMI=body mass index; FPG=fasting plasma glucose; HbA1c=glycated haemoglobin
Identification of at-risk groups
Before interventions can be considered, identification of people at high risk of diabetes needs to take place. The recent development of validated risk tools has allowed clinicians to move beyond simple identification of risk factors, such as obesity and family history. These tools allow a more accurate assessment thereby enabling appropriate use of more intensive interventions in individuals with the highest risk. The tools can be divided into two broad types: those that can be populated with routine computerised data collected in primary care and those that require individuals to self-assess. While the former are suitable for use within primary care, the latter may also be used in a broader range of settings, including workplaces, job centres, local authority leisure facilities, shops, libraries, faith centres, residential and care homes, and day centres. The Leicester Diabetes risk score is an example of a self-assessment tool; it is available on the Diabetes UK website (www.diabetes.org.uk/Riskscore) and has been successfully used at road shows for a number of years.15
Although the NHS Health Check includes an assessment of diabetes, this programme is limited to people aged 40–74 years.16 The NICE guidance recognises that there are people at risk of diabetes who fall outside the Health Check programme and emphasises risk assessment in high-risk groups. It recommends that the following patient groups are encouraged to have a risk assessment for diabetes so they can be offered advice to help them prevent or delay the condition:10
- all adults aged 40 years and above (except pregnant women)
- those aged 25–39 and of South Asian, Chinese, African-Caribbean, or black African descent, and other high-risk black and minority ethnic groups (except pregnant women)
- adults with conditions that increase the risk of type 2 diabetes.
For people at lower risk, opportunities should not be missed to provide brief advice on the risks of diabetes and possible lifestyle modifications. If an individual has been recognised as being at high risk, the next stage of assessment involves a blood test to stratify risk further. The blood test should be offered by GPs and nurses working in primary care and the community, and trained healthcare professionals in secondary care who treat particular conditions where the risk of type 2 diabetes is high. The test could be either a fasting glucose or glycated haemoglobin (HbA1c); it is used to differentiate between those at the highest risk (i.e. fasting blood glucose = 5.5–6.9 mmol/l or HbA1c= 42–47 mmol/mol [6.0%–6.4%]) who should be offered an intensive structured lifestyle programme, from either those at moderate risk (who should be offered brief advice) or those with previously undiagnosed type 2 diabetes (who should be managed according to the NICE guidance for type 2 diabetes).10 A blood test should also be considered for individuals aged 25 and over of South Asian or Chinese descent whose body mass index (BMI) is greater than 23 kg/m2.10
|NICE implementation tools|
NICE has developed the following tools to support implementation of Public Health guidance 38 (Ph28) on Preventing type 2 diabetes—risk identification and interventions for individuals at high risk. The tools are now available to download from the NICE website: www.nice.org.uk/Ph28
NICE support for commissioners
Baseline assessment tool
The baseline assessment is an Excel spreadsheet that can be used by organisations to identify if they are in line with practice recommended in NICE guidance and to help them plan activity that will help them meet the recommendations.
Costing reports are estimates of the national cost impact arising from implementation based on assumptions about current practice, and predictions of how it might change following implementation of the guideline.
Costing templates are spreadsheets that allow individual NHS organisations and local health economies to estimate the costs of implementation taking into account local variation from the national estimates, and they quickly assess the impact the guideline may have on local budgets.
Lifestyle-change programmes for people at high risk of diabetes should be quality assured and culturally appropriate. The NICE guidance specifies that they should be provided to groups of 10–15 people; participants should meet at least eight times over a period of 9–18 months and they should have at least 16 hours of contact time, either within a group, on a one-to-one basis or a mixture of both approaches; alternatively they may use telephone or computer-based interactive media.10
It is recommended that lifestyle programmes encourage people to:10
- undertake a minimum of 150 minutes of moderate-intensity physical activity a week, such as brisk walking, housework, and domestic chores
- aim for an initial weight loss of 5%–10% of their body weight followed by gradual weight loss to reach and maintain a body mass index within the healthy range
- increase consumption of whole grains, vegetables, and other foods that are high in dietary fibre
- reduce the total amount of fat in their diet
- eat less saturated fat.
At present, many areas of the country are lacking lifestyle programmes and it is important that commissioners ensure that these are in place in addition to making sure that diabetes prevention becomes a priority.
While lifestyle interventions are the most effective way of preventing diabetes, it is recognised that not all people are able (or willing) to make the necessary changes, and even if they do, they may still progress towards diabetes. In these circumstances, metformin may be considered alongside lifestyle changes. Orlistat is an alternative for those whose BMI is ?28 kg/m2.10
Certain ethnic minority groups and vulnerable individuals, such as prisoners or those with severe mental illness, are at increased risk of diabetes, but may not be amenable to interventions that work in the wider population.17 The guidance provides specific recommendations for these groups to allow identification of risk and intervention as appropriate.10 These recommendations are of particular relevance to professionals working with these individuals, for example, prison wardens and mental-health workers.
Where possible, the NICE guidance has sought to integrate advice with existing programmes for chronic diseases, such as the NHS Health Check programme and weight-management services, to ensure the most effective use of scarce resources.16 Nevertheless the recommendations will have significant implications for those working in primary care: while the assessment tools are cheap, simple, and quick to use, additional appointments may be needed to provide blood tests for those who are assessed as high risk, but not eligible for an NHS Health Check. Adopting a more structured approach will require the development of care pathways that could be amenable to audit (see suggested audit points). For patients assessed both within and outside the general practice, clear and efficient communication is essential to ensure appropriate follow up of those identified as being at high risk of diabetes. General practitioners will inevitably be at the heart of this activity.
If implemented effectively, the NICE guidance on risk identification and interventions for individuals at high risk should:
- lead to substantial reductions in the number of people developing diabetes
- contribute to alleviating the burden of diabetes to the individual and community.
- The percentage of individuals within primary care databases for whom a diabetes risk can be calculated using routine data
- The percentage of individuals with a high risk of diabetes who are offered a blood test
- The percentage of people who have a fasting glucose of 5.5–6.9 mmol/l or glycated haemoglobin of 42–47 mmol/l (6.0%–6.4%) and are offered a structured intensive lifestyle programme
- The percentage of individuals with a high risk of diabetes who are reassessed at least once a year.
- Commissioners should look to scope with local public health clinicians the impact of the NICE guidance on their local populations
- Health and Wellbeing boards should also consider including diabetes prevention in their Joint Strategic Needs Assessments
- The workload involved is potentially huge so thoughts should be given to targeting risk assessments to people in high-risk groups first
- Some of these groups may not be easy to reach so commissioners should look to public-health specialists for innovative ways of targeting
interventions in hard-to-reach groups
- A multi-agency, multi-professional approach is most likely to be needed so this is an ideal strategy to be led through the Health and Wellbeing Boards
- Commissioners should ensure that they have secured sufficient intensive lifestyle-intervention programmes to meet the needs of those identified as being at risk of developing diabetes.
- Diabetes UK. Diabetes in the UK 2012: key statistics on diabetes. Diabetes UK, 2012. Available at: www.diabetes.org.uk/Documents/Reports/Diabetes-in-the-UK-2012.pdf
- Donnelly R, Emslie-Smith A, Gardner I et al. Vascular complications of diabetes. BMJ 2000; 320 (7241): 1062–1066.
- Hex N, Bartlett C, Wright D, Taylor M. Estimating the current and future costs of type 1 and type 2 diabetes in the UK, including direct health costs and indirect societal and productivity costs. Diabet Med 2012; 29 (7): 855–862.
- Norris S, Kansagara D, Bougatsos C, Fu R. Screening adults for type 2 diabetes: a review of the evidence for the U.S. Preventive Services Task Force. Ann Intern Med 2008; 148 (11): 855–868.
- Tuomilehto J, Lindström J, Eriksson J; Finnish Diabetes Prevention Study Group et al. Prevention of type 2 diabetes mellitus by changes in lifestyle among subjects with impaired glucose tolerance. N Engl J Med 2001; 344 (18): 1343–1350.
- Pan X, Li G, Hu Y et al. Effects of diet and exercise in preventing NIDDM in people with impaired glucose tolerance. The Da Qing IGT and Diabetes Study. Diabetes Care 1997; 20 (4): 537–544.
- Ali M, Echouffo-Tcheugui J, Williamson D. How effective were lifestyle interventions in real-world settings that were modeled on the Diabetes Prevention Program? Health Aff 2012; 31 (1): 67–75.
- Gillies C, Abrams K, Lambert P et al. Pharmacological and lifestyle interventions to prevent or delay type 2 diabetes in people with impaired glucose tolerance: systematic review and meta-analysis. BMJ 2007; 334 (7588): 299.
- Gillies C, Lambert P, Abrams K et al. Different strategies for screening and prevention of type 2 diabetes in adults: cost effectiveness analysis. BMJ 2008; 336 (7654): 1180–1185.
- National Institute for Health and Care Excellence. Preventing type 2 diabetes: risk identification and interventions for individuals at high risk. Public Health Guidance 38. London: NICE, 2012. Available at: www.nice.org.uk/guidance/PH38
- Chamnan P, Simmons R, Forouhi N et al. Incidence of type 2 diabetes using proposed HbA1c diagnostic criteria in the European prospective investigation of cancer—Norfolk cohort: implications for preventive strategies. Diabetes Care 2011 34 (4): 950–956.
- World Health Organization, International Diabetes Foundation. Definition and diagnosis of diabetes mellitus and intermediate hyperglycaemia: report of a WHO/IDF consultation. Geneva: WHO, 2006.
- The DECODE Study Group, the European Diabetes Epidemiology Group. Glucose tolerance and cardiovascular mortality comparison of fasting and 2-hour diagnostic criteria. Archives Intern Med 2001; 161 (3): 397–405.
- National Institute for Health and Care Excellence. Preventing type 2 diabetes.population and community interventions. Public Health Guidance 35. London: NICE, 2011. Available at: www.nice.org.uk/guidance/PH35
- Gray L, Taub N, Khunti K et al. The Leicester Risk Assessment score for detecting undiagnosed type 2 diabetes and impaired glucose regulation for use in a multiethnic UK setting. Diabet Med 2010; 27 (8): 887–895.
- NHS Health Check website. www.healthcheck.nhs.uk (accessed 17 August 2012).
- Taylor J, Cottrell C, Chatterton H et al. Identifying risk and preventing progression to type 2 diabetes in vulnerable and disadvantaged adults: a pragmatic review. Diabet Med 2012; In press. G