What are the other Names for this Test? (Equivalent Terms)
- 1,5-AG Saliva Test
What is 1,5-Anhydroglucitol Saliva Test? (Background Information)
- 1,5-Anhydroglucitol (or 1,5-AG) is a sugar found naturally in nearly all foods. The body is unable to process 1,5-AG, so it remains virtually unchanged. This unique property makes it useful for measuring blood sugar abnormalities in diabetics
- The kidneys normally filter sugars, such as 1,5-Anhydroglucitol and glucose, from blood at a capacity of roughly 180 mg/dL. These sugars then get reabsorbed back into blood and never make it to urine
- The body maintains fairly constant levels of 1,5-AG because, as 1,5-AG is ingested, a roughly equivalent amount gets excreted through urine. Glucose and 1,5-AG compete with each other for reabsorption
- Elevated glucose or 1,5-AG in blood means that some amount of 1,5-AG will be passed through the urine. As the blood levels of 1,5-AG changes, it also changes the levels in saliva
- In other words, high blood glucose (hyperglycemia) will cause decreased amounts of 1,5-AG, and low blood glucose (hypoglycemia) will cause increased amounts of 1,5-AG
- The 1,5-Anhydroglucitol Saliva Test is used to measure 1,5-AG levels in saliva. It is used in diabetics to identify glucose variability and history of high blood glucose, even if other markers like hemoglobin A1c (HbA1c) and blood glucose are normal
The 1,5-AG Saliva Test is composed of two reactions:
- The first reaction renders the glucose in saliva unreactive, so that it cannot react with the compound added in the second reaction
- In the second reaction, a compound is added that reacts with 1,5-AG to make hydrogen peroxide. This is then measured, which is indicative of the amount of 1,5-AG present
What are the Clinical Indications for performing the 1,5-Anhydroglucitol Saliva Test?
Following are the clinical indications for performing a 1,5-Anhydroglucitol Saliva Test:
- Monitoring glycemic control in individuals with diabetes
- Screening ‘at risk’ individuals for diabetes
- Frequent urination, increased thirst
- Blurry vision
- Rapid weight loss
- Tingling and numbing in the extremities
- Giving birth to a baby over 9 pounds
- History of cardiovascular disease
How is the Specimen Collected for 1,5-Anhydroglucitol Saliva Test?
Following is the specimen collection process for 1,5-Anhydroglucitol Saliva Test:
Sample required: Saliva
Process: Spitting into a sterile container.
Preparation required: No special preparation is needed prior to the test.
What is the Significance of the 1,5-Anhydroglucitol Saliva Test Result?
The significance of the 1,5-Anhydroglucitol Saliva Test is explained:
- This test is helpful in detecting sugar control in the past 1-2 weeks, unlike the hemoglobin A1c test that usually gives sugar control over 3 months
- Decreased 1,5-Anhydroglucitol levels may indicate elevated glucose levels
- Low levels of 1,5-AG can also be seen in non-diabetic individuals. Common conditions that may cause low levels are kidney disease, advanced liver cirrhosis, pregnancy, and steroid treatment
- An increasing 1,5-AG level indicates that the diabetes is getting under control. Increased levels can be seen with treatment using Chinese medicines such as polygala, tenuifolia, and senega syrup
The laboratory test results are NOT to be interpreted as results of a "stand-alone" test. The test results have to be interpreted after correlating with suitable clinical findings and additional supplemental tests/information. Your healthcare providers will explain the meaning of your tests results, based on the overall clinical scenario.
Additional and Relevant Useful Information:
- The 1,5-Anhydroglucitol Test is a relatively new test that is rarely performed. However, it has the potential to provide information that more commonly used tests, such as hemoglobin A1c (HbA1c), blood glucose, and fructosamine cannot
- Certain factors influence the results of the test and these include diet, pregnancy, and one’s body composition
- Advantages of the test include that it is a non-invasive test
- Some studies have shown that the test can be used as a screening tool for undiagnosed diabetes, especially in regions where the incidence of diabetes is very high
Certain medications that you may be currently taking may influence the outcome of the test. Hence, it is important to inform your healthcare provider of the complete list of medications (including any herbal supplements) you are currently taking. This will help the healthcare provider interpret your test results more accurately and avoid unnecessary chances of a misdiagnosis.
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