Prediabetes
Examinations and Tests
Your health professional will use a medical history, physical examination, and blood glucose testing to determine whether you have prediabetes and are at risk for developing type 2 diabetes.
Blood glucose testing is usually done after fasting overnight for 8 hours. In some cases, an oral glucose tolerance test (OGTT) may be done. For an OGTT your blood sugar is measured after fasting and then again 2 hours after drinking a special glucose solution. This test is not done as often as the fasting glucose test, which is more convenient.
If the results of your glucose tests are in one of the following ranges, you have prediabetes and are at risk of developing type 2 diabetes:
- Fasting glucose of 6.1 to 6.9 millimoles per litre (mmol/L)
- Oral glucose tolerance (OGT) of 7.8 to 11.0 mmol/L (2 hours after the beginning of the test)
Phrases such as "a touch of diabetes,” “borderline diabetes,” or “your sugar is a little high” are unclear. If you hear these phrases, ask whether your blood sugar level falls within the prediabetes or diabetes range.
If you are diagnosed with prediabetes or type 2 diabetes, your health professional may also do a thorough examination of the cardiovascular system
and check your blood pressure and cholesterol levels. Your health professional may also test your blood sugar periodically to check for diabetes.
Early Detection
The Canadian Diabetes Association recommends screening for prediabetes—which may lead to type 2 diabetes—if you:13
- Are 40 years of age or older—particularly if you are overweight—and you have never had your blood glucose (sugar) tested or you have not been tested in more than 3 years.
- Are younger than 40, overweight—body mass index, BMI, of 25 or greater—and have one or more other risk factors for type 2 diabetes. These include:
- High blood pressure, over 130/80 millimetres of mercury (mm Hg).
- Abnormal cholesterol. People who have high-density lipoprotein (HDL) cholesterol levels of 0.9 millimoles per litre (mmol/L) or less or triglyceride levels of 2.8 mmol/L or more are at increased risk for developing type 2 diabetes.5
- A family history of type 2 diabetes. People who have a parent, brother, or sister with prediabetes or type 2 diabetes have a greater risk of developing the disease than adults without a parental history of the disease.
- History of gestational diabetes or having a baby weighing more than 9 lb (4 kg). Women who have had gestational diabetes or who have had a large baby are at greater risk for getting type 2 diabetes later in life.5
- Race and ethnicity. People of African, Hispanic, Aboriginal, Asian, and Pacific Island descent are at greater risk for getting type 2 diabetes than whites.5
- Having schizophrenia.
- Having polycystic ovary syndrome, a condition that causes a hormone imbalance in women.
- Having a skin condition called acanthosis nigricans that results in darkened skin and velvety wart-like growths.
- Are overweight and get little or no exercise and want to help reduce your risk for getting type 2 diabetes.
If your fasting blood glucose (sugar) level is between 5.7 and 6.1 millimoles per litre (mmol/L), you may have an oral glucose tolerance test (OGTT) to rule out prediabetes.
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| Author: | Carrie Henley Robin Parks, MS | Last Updated: November 7, 2006 |
| Medical Review: | Caroline S. Rhoads, MD - Internal Medicine Tom Bailey, MD - Family Medicine Matthew I. Kim, MD - Endocrinology & Metabolism | |
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