April 3, 2012
Another Reason for Not Diagnosing Based on A1c
Ever since the American Diabetes Association made the recommendation of using the A1c for diagnosing diabetes and prediabetes, more studies are showing this to be a questionable decision. One study that I had found in the past is no longer available as when I click on the link the message I get is “page not found.” Apparently, there were some reasons for the study to have been pulled.
The A1c has been proven ineffective for use on people undergoing dialysis. This is not done for diagnosis, but should cast some serious doubts on the reliability of the A1c test for all tests. There is still a lot of discussion that for non-whites, the test is not an accurate reflection as it is for white Anglo-Saxons. Some are openly stating that the A1c test needs to be standardized for each ethnic group.
This makes sense as each ethnic group can be very different and react to medications differently. My own wife reacts very differently to medications that do not create problems for me.
Now we learn that another study proclaiming that the A1c cannot be used for diagnosis on people with iron-deficiency anemia. This study does come out of India, but highlights a very real problem in populations that are iron-deficient. Iron-deficiency increases erythrocyte survival. This elevates HbA1c concentrations at a glycemic level disproportionately.
This in turn gives a diagnosis of prediabetes or diabetes when in fact neither may be the case or prediabetes may be the correct diagnosis. The study clearly points out the problems for nutritionally compromised populations, in other words, more than half of the world's population.