The basic glucose tolerance test may be ordered by your physician as part of a complete physical examination or specifically because diabetes is suspected. It involves taking a small specimen of blood from a vein in your arm. Over approximately a several hour period, multiple separate readings of your blood glucose level are taken. These measurements, when plotted on a graph, graphically portray how your body handles glucose. The test is especially valuable because it can confirm the presence of a condition known as impaired glucose tolerance. While people who have impaired glucose tolerance do have elevated blood glucose levels after meals, impaired glucose tolerance is not necessarily diabetes, and their fasting blood sugar is normal. However, people who have this condition may be more likely than others to develop active diabetes.

If your physician orders a glucose tolerance test, it will be scheduled in the morning after you have had three days of good food intake so that your body can handle sugar optimally. You will be asked not to eat breakfast that morning so that your first blood sample will reflect your fasting glucose level. Next you will be given a beverage or test meal containing glucose to drink or eat. On some occasions glucose is administered intravenously. At various hourly intervals after you have taken the glucose, blood samples will be taken and the glucose level of your blood will be measured.

This test is usually not used by physicians during periods of long dietary restriction, illness, or disability or without the three ­day good food intake preparation. If you do not have diabetes or impaired glucose tolerance, the resulting readings, plotted on a graph, will show a normal pattern. If you do have diabetes, the graph will show that your blood glucose level rose and kept rising and did not even begin to drop by the end of the test. If you have impaired glucose tolerance, the graph will look much like the non-diabetics graph, but it will indicate higher blood sugar concentrations with normal fasting or end-of-test levels. The levels will fall between the range of the non-diabetic and the diabetic on the graph. The term impaired glucose tolerance refers to the condition in which the fasting plasma glucose level is between normal and diabetic levels. This term is used instead of the term borderline, chemical or latent diabetes.

If a glucose tolerance test reveals that you have impaired glucose tolerance, your doctor may recommend that you have further tests. Also, because people with impaired glucose tolerance are, more likely to develop diabetes, and because at this stage diabetes is preventable, your doctor may advise you to lose weight, cut your intake of simple sugars, exercise more, and avoid cardiovascular risk factors, including high blood pressure, smoking, and high cholesterol levels.

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This entry was posted on Wednesday, July 18th, 2007 at 3:40 am and is filed under Diabetes News. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.