One of The Most Common Diagnostic Tests for Diabetes is Not as Effective in Children
A recent study found that a common test to diagnose type 2 diabetes is not as effective in children as it is in adults. This test, called a hemoglobin A1c (or HbA1c) is easier to perform because this test estimates blood sugar for the past 2 to 3 months using an immediate sample of blood, no waiting required. The other two main tests, a blood glucose test and a glucose tolerance test, are more intensive and are, therefore, harder to administer to children.
Usually an HbA1c test is highly effective at determining a diagnosis but this test alone cannot be relied upon when testing children because the test has been found to be less sensitive. According to the American Diabetic Association, a diagnosis of type 2 diabetes is given when the HbA1c level is 6.5% or more while pre-diabetes is diagnosed when HbA1c levels falls between 6% and 6.4%.
Almost all of the studies that were done previously to find effective testing procedures were done on adults. A pediatric endocrinologist at Mott Children’s Hospital in Ann Arbor, Joyce Lee MD indicated that there are hormonal differences in children that may skew the results. She further indicated that HbA1c levels naturally rise over time anyway and therefore, a lower threshold indicator should be included when testing a child using the HbA1c test.
Gerald Bernstein MD, of the Friedman Diabetes Institute, agrees with this assessment. He says that as hormones change, especially as erratically as they do in children, the test can be unreliable.
Therefore, a full assessment by a doctor is needed to determine if a child has type 2 diabetes. Your child’s doctor may want to begin an assessment for type 2 diabetes if the child has a weight above the age and gender related 85th percentile, or more than 120% above a pre-described ideal weight. This isn’t all that doctors’ should look at before giving diagnostic tests. Many doctors believe that at least 2 risk factors need to also be present before testing can commence. These risk factors include genetics and ethnicity. Also, signs that insulin is not produced properly such as high blood pressure, higher than normal liver enzymes and skin problems associated with acanthosis nigricans or symptoms of polycystic ovary syndrome, a hormone problem associated with the interference of ovulation.
The assessment should also include blood glucose testing. If the child has no diabetes symptoms, two blood tests should be done on separate days for confirmation of a diagnosis. The traditional diagnostic blood tests used include a fasting blood sugar test which is done after abstaining from eating or drinking for at least 8 hours and a glucose tolerance test which includes testing 2 hours after drinking a sweet carbohydrate drink and a hemoglobin A1c test. The fasting blood sugar test is the preferred test for any age.
If your child does have risk factors that may develop into type 2 diabetes, make sure your child’s doctor does more testing even if an HbAc1 test is high. Remember, the earlier diabetes is diagnosed, the easier it will be to control over the child’s lifetime.