What are the signs and symptoms?
People with IGT often have no symptoms. In fact, millions of people
have diabetes and don't know it because symptoms develop so gradually, people
often don't recognize them. Symptoms of diabetes include the following:
- frequent urination
- constant thirst
- always being tired
- blurred vision
- cuts and bruises that are slow to heal
- frequent infections
- tingling or numbness in your hands or feet
How is IGT diagnosed?
IGT is diagnosed using the oral glucose tolerance test. After fasting
for 8-12 hours, a person's blood glucose is measured before and 2 hours
after drinking a glucose-containing solution.
- A person with normal tolerance has a blood glucose level below 140 mg/dL 2 hours after drinking the glucose solution.
- A person with impaired glucose tolerance has a blood glucose level between
140 mg/dL and 199 mg/dL after
two hours.
- A person with two-hour fasting glucose levels 200 mg/dL
or higher may have diabetes.
IGT can also be detected with the fasting blood glucose tolerance test. In
this test, a person's blood glucose is measured after a fast of 8-12 hours
(without drinking a glucose solution).
A person with normal tolerance has a fasting blood glucose level below 110 mg/dL.
A person with impaired glucose tolerance has a fasting blood glucose level
between 110 mg/dL and 125 mg/dL.
A person with fasting glucose levels 126 mg/dL or higher
may have diabetes.
How often should I be tested?
If your blood glucose levels are in the normal range, it is reasonable to be
retested every 3 years. If you have IGT, you should be tested for type 2
diabetes every 1-2 years after your diagnosis.
Prevention
If you are at risk of developing IGT, you can help delay or prevent
the onset with healthy eating, weight loss, and regular exercise.