Best Evidence Summary for Prevention of Type 2 Diabetes for Adults

Diabetes is a disease that affects the body’s ability to control glucose (sugar) levels.

There are two main types of diabetes:

• Type 1 – when the body can’t produce enough insulin, which is a substance that helps control glucose. People with Type 1 diabetes need to be given injections of insulin to stay well.
• Type 2 – when the body is still making some insulin, but it is not able to be used properly by the body. Regular medication is needed to help control glucose. (5)

Type 2 diabetes can be prevented or delayed by:

• Walking or any other exercise or movement for at least 30 minutes a day
• Eating foods that release glucose more slowly than the foods which give a quick release of sugar –slow release foods are called low GI (low glycaemic index foods)
• Lose at least 5-7% of weight. So a 100 kg person who loses 5-7kgs reduces their risk of Type 2 diabetes or delays getting Type 2 diabetes. (5)

Health professionals should encourage and support patients to try these things first. Some patients may still need medication and/or surgery to help them. When needed, the evidence suggests that medications such as metformin, acarbose, rosiglitazone and orlistat are effective in preventing/delaying the onset of type 2 diabetes in high risk individuals. For high risk people who are very overweight (morbidly obese) bariatric (stomach) surgery can prevent or delay progression to type 2 diabetes. (5)

Why worry about Type 2 diabetes?
Type 2 diabetes has a major impact on health and the cost of health care. Type 2 diabetes causes the fine blood vessels in the body to block up and not work properly, which can lead to:

• heart disease and stroke
• foot sores that lead to ulceration, gangrene and lower limb amputation (people often lose feeling in their feet and sores are hard to heal- important to talk about foot care and regular checking of feet)
• kidney failure
• problems with eyes (Type 2 diabetes is the most common cause of blindness in people under 60 in Australia)
• erectile dysfunction (problems for men having sex)

Who is at risk for developing type 2 diabetes?

• People with a family history of Type 2 diabetes
• Men
• Some ethnic groups -people born in Southern Europe, in North Africa and the Middle East or in the Pacific Islands and South Asia and especially Aboriginal and Torres Strait Islander peoples
• People who were born with a low birth weight
• People who are overweight or use to be obese
  • A high BMI (body mass index- the measure of overall fat in the body) is a significant predictor of type 2 diabetes.
  • Obese men are at higher risk than obese women, especially those with fat deposited within the abdomen around the body organs
• People who do little or no physical activity – sedentary
• Age increases the prevalence and risk until age 75
• Dietary intake – people who don’t eat a lot of high GI, fatty foods
• People who smoke
• People who have a lot of stress in their lives
• People who have other illnesses or conditions such as
• Gestational Diabetes Mellitus (GDM) –diabetes in pregnancy
• Polycystic Ovary Syndrome
• The Metabolic Syndrome (5)

What can practitioners do?

• Identify people at high risk by using The Australian Risk Assessment Tool (AUSDRISK) (www.diabetesaustralia.com.au/For-Health-Professionals/Diabetes-National-Guidelines/ p117)
• Risk assessment should begin at age 40 or from age 18 in Aboriginal and Torres Strait Islanders*.
• Risk assessment should be repeated every 3 years.
• Educate about lifestyle, -activity, diet, risk factors (5)

The key message from the evidence is that Type 2 diabetes can be prevented or delayed by:

• early detection of risk, through the use of appropriate assessment tools
• community and individual education about risk factors
• regular review and support with Type 2 diabetes prevention efforts and/or management

This will reduce the significant burden on people, their families, and the health resources of the country.
Aboriginal Health Practitioners can make a difference to improved outcomes for Aboriginal communities by helping people know their risk for Type 2 diabetes, educating about the prevention or delay of this disease and using best practice for management.

References
1. Abuissa H, Bell D, O’Keefe J (2005). Strategies to prevent type 2 diabetes. Curr Med Res Opin 21:1107-1114.
2. Australian Institute of Health and Welfare (AIHW) (2008). Diabetes: Australian Facts 2008. Diabetes Series No. 8. Cat. no. CVD 40. AIHW, Canberra, Australia.
3. Bako A, Morad S, Atiomo W (2005). Polycystic ovary syndrome: an overview. Rev in Gynaecol Pract 5:115-122.
4. Barry E, Magliano D, Zimmet P, Polkinghorne K, Atkins R, Dunstan D, Maurray S, Shaw J (2006). AusDiab 2005. The Australian Diabetes, Obesity and Lifestyle Study. International Diabetes Institute, Melbourne, Australia.
5. Dunstan D, Zimmet P, Welborn T, De Courten M, Cameron A, Sicree R, Dwyer T, Colagiuri S, Jolley D, Knuiman M, Atkins R, Shaw J (2002). The rising prevalence of diabetes and impaired glucose tolerance: the Australian Diabetes, Obesity and Lifestyle Study. Diabetes Care 25(5):829-834.
6. International Diabetes Federation (IDF), 2006. Diabetes Atlas, third edition, 1H http://www.eatals.idf.org (accessed
7. Magliano D, Barr E, Zimmet P, Cameron A, Dunstan D, Colagiuri S, Jolley D, Owen N, Phillips P, Tapp R, Welborn T, Shaw J (2008). Glucose indices, health behaviors, and incidence of diabetes in Australia: the Australian Diabetes, Obesity and Lifestyle Study. Diabetes Care 31(2):267-272.
8. Chen L, Magliano DJ, Balkau B, Colagiuri S, Zimmet PZ, Tonkin AM, Mitchell P, Phillips PJ, Shaw JE (2009). An Australian type 2 diabetes risk assessment tool based on demographic, lifestyle and simple anthropometric measures. Med J Aust (in press).
9. Colagiuri R, Thomas M, Buckley A (2007). Preventing Type 2 Diabetes in Culturally and Linguistically Diverse Communities in NSW. NSW Department of Health, Sydney, Australia.
10. Colagiuri S, Colagiuri R, Conway B, Grainger D, Davy P (2003). DiabCo$ Australia: Assessing the burden of type 2 diabetes in Australia. Diabetes Australia, Canberra.
11. Craig M, Femia G, Broyda V, Lloyd M, Howard N (2007). Type 2 diabetes in Indigenous and non-Indigenous children and adolescents in New South Wales. Med J Aust 186:497-499.
12. Drichoutis A, Lazaridis P, Nayga R (2006). Consumers’ Use of Nutritional Labels: A Review of Research Studies and Issues. Academy of Marketing Science 2006:1-26
13. WHO (2006). Definition and Diagnosis of Diabetes Mellitus and Intermediate Hyperglycaemia. World Health Organisation, Geneva.
14. Wilson P, Meigs J, Sullivan L, Fox C, Nathan D, D’Agostino R (2007). Prediction of incident diabetes mellitus in middle-aged adults. The Framingham Offspring Study. Arch Int Med 167:1068-1074.
15. Yamaoka K & Tango T (2005). Efficacy of lifestyle education to prevent type 2 diabetes. A meta-analysis of randomized controlled trials. diabetes Care 28:2780-2786.

16. ¹ Colagiuri R, Girgis S, Gomez M, Walker K, Colagiuri S, O’Dea K. National Evidence Based Guideline for the Primary Prevention of
Type 2 Diabetes. Diabetes Australia and the NHMRC, Canberra 2009.
www.diabetesaustralia.com.au/For-Health-Professionals/Diabetes-National-Guidelines/