If you have impaired glucose tolerance (IGT for short), your body is slow at getting your blood glucose (sugar) level back to normal after you eat.

In healthy people, the level of glucose in their blood rises after a meal. Then it drops down to normal in one to two hours. But if you have impaired glucose tolerance, it can take at least three hours for your blood glucose level to get back to normal after you eat.

Doctors use two blood tests to check for this condition.

Doctors check for this condition with a test called an oral glucose tolerance test. If your glucose level on this test is above 139 mg/dL but below 200 mg/dL, you have impaired glucose tolerance.

 

 

 

 

 

Source:
British Cardiac Society, British Hypertension Society, Diabetes UK, et al.
JBS 2: Joint British Societies' guidelines on prevention of cardiovascular disease in clinical practice.
Heart. 2005; 91: 1-52.

 

 

 

 

 

¹ (The term mg/dL stands for milligrams per deciliter.)

Your doctor may also check for another condition called impaired fasting glucose by doing a test called a fasting plasma glucose test. If your level on this test is above 99 mg/dL but below 126 mg/dL, doctors say you have impaired fasting glucose.

If you have either of these conditions, your doctor may say you have pre-diabetes.

Having impaired glucose tolerance means you're more likely to get diabetes. You might also be more likely to get

 

 

 

 

 

heart disease
You get heart disease when your heart isn't able to pump blood as well as it should. This can happen for a variety of reasons.

 

 

 

 

 

heart disease.

 

 

 

 

 

Source:
National Institute of Diabetes and Digestive and Kidney Diseases.
Diagnosis of diabetes.
October 2008. Available at http://diabetes.niddk.nih.gov (accessed on 19 November 2009).

 

 

 

 

 

²

If you have impaired glucose tolerance or impaired fasting glucose, your doctor will want to test your blood glucose level regularly. And he or she will talk with you about ways to lower your chances of getting diabetes.

Some women have high levels of glucose in their blood when they are pregnant. This is called gestational diabetes. If you get this kind of diabetes, it can be harmful to both you and your baby if it isn't treated.

If you're pregnant, you should have regular checkups that include a test for diabetes. This is especially important if:

Many women with diabetes in pregnancy can control their diabetes just by watching what they eat. Others have to take insulin injections during pregnancy. Ask your doctor which treatment is best for you.

If you have gestational diabetes, it will probably go away after your baby is born. But you're about seven times more likely to get type 2 diabetes later in life, compared to women who don't get diabetes in pregnancy.

 

 

 

 

 

Source:
Bellamy L, Casas JP, Hingorani AD, et al.
Type 2 diabetes mellitus after gestational diabetes: a systematic review and meta-analysis.
Lancet. 2009; 373(9677): 1773-1779.

 

 

 

 

 

³

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