Your doctor may perform diabetes-related tests if you have symptoms such as severe thirst, frequent urination, unexplained weight loss, increased hunger, or tingling in your hands or feet.
According to the Centers for Disease Control and Prevention (CDC), about 29 million children and adults (or more than 9% of the population) in the United States have diabetes. However, millions of Americans do not know they have diabetes because there may be no signs. To confirm a diagnosis of type 2 diabetes, doctors will prescribe a fasting blood glucose test or a random blood glucose test.
Fast-belly blood glucose test
The American Diabetes Association (ADA) says fasting blood glucose testing (FPG) is the preferred method for diagnosing diabetes because it is easy to do, convenient, and less expensive than other tests.
What should I do to prepare for the test?
Fast for at least 8 hours before the blood glucose test.
What will be done during the test?
During the blood glucose test, blood will be drawn and sent to the lab for analysis.
How are the results of the blood glucose test determined?
For people who do not have diabetes, normal fasting blood glucose is between 70 and 100 mg/dl. The diagnosis of diabetes is made when two separate blood tests show a fasting blood glucose level greater than or equal to 126 mg/dl.
However, if fasting blood glucose is normal, but there are risk factors for developing diabetes or symptoms of diabetes, your doctor may decide to perform a glucose tolerance test to verify that you have diabetes.
Some people have normal fasting blood glucose results, but their blood glucose rises rapidly after eating. These people may have impaired glucose tolerance. If blood glucose levels are high enough, a diagnosis of diabetes may be made.
Random blood glucose testing
Random blood glucose testing is another way to diagnose diabetes, measuring blood glucose without regard to the time of the last meal. Fasting is not required prior to this test.
Glucose levels greater than 200 mg/dl may indicate diabetes, especially if the test is repeated at a later time and shows similar results.
Oral glucose tolerance test
Oral glucose tolerance testing is another method used to detect diabetes, but is usually used only during pregnancy to diagnose gestational diabetes, or in people suspected of having type 2 diabetes but with normal fasting glucose levels, and may also be used to diagnose prediabetes.
Glycosylated hemoglobin test
The glycosylated hemoglobin (HbA1c) test is an important blood test for diabetes to determine diabetes control. This diabetes test provides an average of blood glucose control over a 6-12 week period and is used in combination with home blood glucose monitoring to adjust diabetes medications. If a value of HbA1c is found to be equal to or greater than 6.5%, diabetes may be considered.
Other diabetes tests
In addition to HbA1c testing, it is important for people with diabetes to have a dilated eye exam (as part of a comprehensive eye exam) at least once a year. This important test can detect early signs of retinopathy, which may not have any symptoms in its early stages. It is necessary to have a foot exam once or twice a year (or at each visit) to detect any diminished circulation and incurable sores. Early detection of eye and foot problems in people with diabetes allows the doctor to prescribe appropriate treatment.
Diabetes screening in children
Many children do not have any symptoms until they are diagnosed with type 2 diabetes. Most of the time, diabetes is found when blood or urine tests done for other health problems show diabetes.
Check with your doctor about your child’s risk of developing diabetes. If your child’s blood glucose tests are higher than normal but have not yet reached the level of diabetes (called prediabetes), your doctor may provide guidance on specific diet and exercise to help your child avoid developing diabetes. Most children with type 2 diabetes or prediabetes are overweight or obese.
Learning to live with diabetes
Diabetes can cause serious health problems if blood sugar is not controlled. You can stay healthy and feel good if you follow the treatment plan recommended by your doctor and maintain a healthy lifestyle. By making smart food choices, exercising regularly, maintaining a normal weight, reducing stress, and making other modest lifestyle changes, living with diabetes will be easier.