According to new research, the hemoglobin A1c blood test underestimates the occurrence of diabetes while diagnosis.
“Based on our findings, A1c should not be solely used to determine the prevalence of diabetes,” said the lead researcher, Ms. Maria Mercedes Chang Villacreses. “It should be used in conjunction with the oral glucose test for increased accuracy.”
The hemoglobin A1c is a type of test that displays the average blood sugar level in the past 2-3 months. Those who are suffering from diabetes usually go through this test to check whether their blood sugar level is in the required range. The test is for the diagnosis of both type 1 and 2 diabetes. This test is also preferred because no preparation is required for it.
An oral glucose tolerance test observes the body’s response to glucose. For this test, the blood of a person is taken following an overnight fast and once again after two hours of taking a sugary drink. This test is used for the diagnosis of type 2 diabetes.
The new study included 9,000 adults without a diabetes diagnosis. The participants got both an A1c test and an oral tolerance glucose test, and the researchers compared the results. The researchers found the A1c test didn’t catch 73 percent of diabetes cases that were detected by the oral glucose test. “The A1c test said these people had normal glucose levels when they didn’t,” said Ms.Chang Villacreses.
The researchers also believe that race and ethnicity have a strong impact on the test’s accuracy. They also found that detecting abnormal glucose level was more likely in non-Hispanic whites as compared to the non-Hispanic blacks or just Hispanics.
“Our results indicated that the prevalence of diabetes and normal glucose tolerance defined solely by A1c is highly unreliable, with a significant tendency for underestimation of the prevalence of diabetes and overestimation of normal glucose tolerance,” Chang Villacreses further added.