Caring Currents

Diabetes A1c Test: New Use for an Old-Line Tool

Last updated: Aug 28, 2008


Last week I wrote about how the A1c test , the current gold standard for monitoring long-term blood sugar control in people with diabetes, may soon be replaced by a new measure, the estimated average glucose (eAG) test.

Now it appears the old A1c test may be put to new use. A team lead by an edocrinologist at the Johns Hopkins University School of Medicine is recommending that the A1c measure be used to identify potentially millions of people with undetected diabetes.

Current diagnostic tests designed to detect diabetes are limited, according to the team, as they only measure the amount of sugar present at the time a blood sample is taken. The A1c doesn't require a person to fast overnight, another significant advantage over both currently available screening tests: the oral glucose tolerance test and the fasting blood glucose test .

Diabetologists suggest the current screening tests may miss a significant portion of the population that has diabetes or is at high risk of developing the disease, since glucose levels can vary depending on a person's diet and activity for several days leading up to a blood draw. (And, let's be honest, who's going to admit to trying to skew results by skipping doughnuts and ice cream and taking a brisk walk in the days leading up to a sugar check?)

A national panel from The Journal of Clinical Endocrinology & Metabolism recommended that folks who score a 6 percent on an A1c test may be at risk for diabetes and should be followed closely. Those who hit 6.5 percent or higher should be considered to have diabetes, if a subsequent check confirms initial test results. Among seniors 70 and over, some geriatricians say shooting for a slightly higher A1c, around 7.5 percent, is more realistic. (And in the frail elderly, that number may climb even higher, depending on an individual’s other health concerns and whether or not diabetes-related complications are a factor.)

Speaking of shifting numbers -- exactly when diabetes is diagnosed and in whom -- is the subject of an eye-opening post by David Kliff, who has type 2 insulin-dependent diabetes, and blogs about the big business of diabetes at the Diabetic Investor . (His insights on the whole quandary about use of the term "pre-diabetes " is particularly illuminating, especially for anyone with numbers hovering in that gray zone.)  And he weighs in wittily on the whole A1c vs. eAG debate.

Of course, all this talk about 6s and 7s begs the question: What's a person to do if he or she is concerned about being at risk for diabetes? Simple, ask a physician about the benefits of taking an A1c test instead of standard screening checks.

Whatever screening measure you and your doctor decide to use, don't wait to be tes ted . The sooner you find out if you have the disease the sooner you can take steps to prevent its brutal complications, which can damage the body from head to toe.

Image by Flickr user kr4gin used under the Creative Commons attribution license.