Diabetes Care
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

This Article
Right arrow Full Text (PDF)
Right arrow Purchase Article
Right arrow View Shopping Cart
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow Request Permissions
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Nuttall, F. Q.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Nuttall, F. Q.
Social Bookmarking
Add to CiteULike   Add to Del.icio.us   Add to Digg   Add to Reddit   Add to Technorati  
What's this?

Diabetes Care, Vol 21, Issue 9 1475-1480, Copyright © 1998 by American Diabetes Association

ARTICLES

Comparison of percent total GHb with percent HbA1c in people with and without known diabetes

FQ Nuttall
Minneapolis Veterans Affairs Medical Center, Department of Medicine, University of Minnesota, 55417, USA.

OBJECTIVE: To directly compare results obtained using an ion-exchange high-performance liquid chromatography (HPLC) HbA1c method used in the Diabetes Control and Complications Trial with two different affinity chromatography methods in which "total GHb" is determined. RESEARCH DESIGN AND METHODS: Blood was obtained from a large number of people with and without known diabetes. The specimens were divided and assayed for HbA1c and for total GHb. Total GHb was determined using a semi-automated gravity-elution boronate affinity chromatography method and an automated boronate affinity HPLC method. The results obtained with the two methods were also compared. RESULTS: In subjects without known diabetes, the mean percentage HbA1c and the range of values were similar to the total GHb values in the same subjects when assayed using the semi-automated affinity gravity-elution method (mean 5.2 +/- 0.4 and 5.1 +/- 0.4% [SD], respectively). With the affinity HPLC method, results were 5.3 +/- 0.4%. The similarity in results was surprising. However, analysis of the data suggests that a large proportion of the material in the HbA1c fraction measured using this ion-exchange HPLC method is not GHb, as pointed out by others. Although the results were similar in people without known diabetes, in the people with diabetes, the incremental increase was approximately 25% greater for the total GHb when compared with the increase in HbA1c. When corrected for the non-GHb being measured by the HbA1c method, it can be calculated that approximately 40% more GHb is measured using affinity chromatography over the entire range of GHb values. CONCLUSIONS: The similarity in the mean and range of percent HbA1c and in percent total GHb using these different methods can be attributed to two factors: 1) the HbA1c ion-exchange method measures only approximately 50-60% of the total GHb present, and 2) approximately 40-50% of the material being measured in the HbA1c fraction is not GHb, i.e., offsetting factors fortuitously resulted in values similar to the more specific affinity methods. The greater incremental increase in percent total GHb compared with percent HbA1c in people with diabetes can be attributed to the greater amount of GHb being measured with the affinity methods.
Add to CiteULike CiteULike   Add to Del.icio.us Del.icio.us   Add to Digg Digg   Add to Reddit Reddit   Add to Technorati Technorati    What's this?




HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Diabetes Diabetes Care Clinical Diabetes Diabetes Spectrum
Copyright © 1998 by the American Diabetes Association.