Testing for abnormal glucose metabolism is an important part of diagnosing diabetes. High blood glucose levels indicate that sugar in the body is not making its way into the cells to be used for energy. Advances in technology have lead to new and improved methods of testing, increased levels of accuracy and the ability for most people to test their blood sugar levels in their own homes.
Urine Testing
One of the oldest and most simple methods, this tests for the presence of sugar or ketones in the urine. Sugar in the urine indicates a blood sugar level well above normal, evidenced by glucose being excreted from the body. Ketones are a compound the body forms when it cannot access sugar for energy. These are flushed out through the urine, and their presence indicates that sugar is not available to the body's cells. Presence of these two compounds most commonly indicates diabetes. This test is not as specific as blood levels for measuring glucose.
Fasting Blood Glucose
This test is performed after an overnight fast of at least eight hours. The ideal result is below 99 mg/dL. Levels above 126 mg/dL are indicative of diabetes. The test should be repeated at least once to confirm the fasting glucose level. Other conditions, such as acute infection, can also cause a higher-than-normal glucose reading.
Glucose Tolerance Test
This test measures the body's response to a load of glucose, which is impaired in people with diabetes. After an overnight fast, the patient is given a measured amount of glucose in the form of a cola syrup. The blood glucose level is drawn before the glucose load and is then measured at 30 minutes, one hour, two hours and three hours later. Normally, the glucose level rises after 30 minutes and then returns to normal. In impaired glucose metabolism, the blood sugar level remains high for a longer period of time. At the two-hour draw, a level over 200 mg/dL is diagnostic of diabetes.
Glycolated Hemoglobin
According to Lab Test Online, this test, also known as hemoglobin A1C, measures a person's average blood glucose level over the past two to three months. In 2009, an expert committee composed of members of the American Diabetes Association, the International Diabetes Federation and the European Association for the Study of Diabetes proposed the A1C test be the primary diagnostic test for diabetes. Levels above 6.5 percent are diagnostic of the condition. Benefits over the other diagnostic tests include accuracy and convenience, as the patient does not have to fast or have the study repeated for confirmation.
Random Finger Stick
Lab Tests Online describes this as an at-home method to monitor blood glucose levels. The finger is pricked, and a small drop of blood is placed on a strip, which is inserted into a device called a glucometer. A reading of the blood sugar level is displayed in less than a minute. This test can be done several times each day to help people with diabetes monitor their conditions and adjust their diets accordingly.
