Diabetes Center

Diabetes Diagnosis

Anyone 45 years old or older should consider getting tested for pre-diabetes and type 2 diabetes. If you are younger than 45, overweight, and have one or more of the risk factors, you should consider getting tested for diabetes. If you are 45 or older and overweight, diabetes testing is strongly recommended.

Medical exams
If you suspect that you might have diabetes, see your primary doctor first and request diabetes testing. Screening tools such as urine samples and glucose tests can identify problems that need to be addressed, but these tests are not sensitive enough for monitoring or diagnosing diabetes.  Instead, the primary method for testing for diabetes is with very specific blood tests.

Blood tests
Diabetes is diagnosed via blood tests. Test results indicating that a person has diabetes or pre-diabetes should be confirmed with a second test on a different day. In order to determine whether or not you have diabetes, ask your doctor for a fasting blood glucose test or an oral glucose tolerance test. Blood glucose testing can be used to screen healthy, asymptomatic individuals for diabetes and pre-diabetes because diabetes is a common disease that begins with few symptoms. The following tests are used to confirm or exclude a diabetes diagnosis:

Fasting plasma glucose (FPG) test or fasting blood glucose (FBG) - These tests are used to detect diabetes and pre-diabetes and are most reliable when taken in the morning. The FPG test measures blood glucose in a person who has not eaten anything for at least 8 hours and is commonly used for non pregnant adults and children. Diabetes is diagnosed when blood glucose level = 126 (mg/dL) and 7 mmol/L or higher.  Normal readings for FBG tests are 3.5 -  6.5 mmol/L.  Below mmol/L 3,5 is diagnosed as hypoglycaemia. A reading above 6.5 mmol/L is diagnosed as hyperglycemia.

Oral glucose tolerance test (oGTT)- An oGTT measures blood glucose after a person fasts at least 8 hours and 2 hours after the person drinks a glucose-concentrated beverage. This test can be used to diagnose diabetes and pre-diabetes. Diabetes is diagnosed when blood glucose level is 200 mg/dL or higher 2 hours after drinking a beverage containing 75 grams of glucose dissolved in water.

Random plasma glucose test -  This test, along with an assessment of symptoms, is used to diagnose diabetes but not pre-diabetes.  Also called a "casual plasma glucose test", this test measures blood glucose without regard to food intake. Diabetes is diagnosed when blood glucose level is 200 mg/dL or higher.

Laboratory tests
Several other laboratory tests may be used to monitor diabetes, evaluate organ function, and detect emerging complications. These include:

1.      Cholesterol and lipid tests - Cholesterol, HDL cholesterol, LDL cholesterol, Lipid profile, Triglycerides

2.      Insulin production - C-peptide, Insuline

3.      Kidney function tests - BUN, CMP, Creatinine, Creatinine clearance, Cystatin C, EGFR, GFR, urine microalbumin

High levels of glucose most frequently indicate diabetes, but many other diseases and conditions can also cause elevated glucose.  Based on the results of the tests above, your doctor will tell you if you have normal blood glucose, pre-diabetes, or diabetes.  It is important to note, however, that testing should be done twice at different times in order to confirm a diagnosis of diabetes. Once you have been diagnosed with type 1, type 2 or gestational diabetes, you can start to seek information about treatment alternatives.  Read on for more ideas about preventing diabetes in cluding how to treat diabetes here.

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