What Is Estimated Average Glucose?
Diabetes patients may be walking away from their medical appointments armed with new information to help them better improve and manage their diabetes. Like the familiar A1C test, the estimated average glucose, or eAG, is derived from glucose values taken over the course of three months.
The eAG, however, is not reported as a percentage but in the same values seen via daily self-monitoring – mg/dl or mmol/L. The formula for determining average glucose is 28.7xA1C-46.7 = eAG.
The following chart translates A1C percentages into eAG:
If your A1C is this:eAG (Estimated Average Glucose) is this:
% mg/dl mmol/l
10.0% 240 13.4
9.0% 212 11.8
8.0% 183 10.1
7.0% 154 8.6
6.0% 126 7
The new eAG term was introduced to help stem confusion after a new worldwide standardization of A1C analyses was set. The new values are 1.5 to 2 percentages points lower than the current standard. In addition, the new values were reported in millimoles per mole (mmol/L), whereas A1C results were always reported as percentages.
An international study was then conducted to look at the relationship between HbA1c and average glucose. The A1C-Derived Average Glucose Study revealed a close relationship between HbA1C and AG (average glucose). This relationship is the eAG, which applies to patients with both type 1 and type 2 diabetes. This new terminology now focuses on a single set of values for both daily glucose checks and long-term control.
SOURCE: American Diabetes Association. Estimated Average Glucose.