Assessment of glucose tolerance test criteria for diagnosis of diabetes in Chinese subjects.
OBJECTIVE
To examine and compare WHO diagnostic criteria for diabetes mellitus.


METHODS
The relationship between FPG and 2-h glucose are examined in 680 OGTTs with a quadratic regression model and ROC analysis. Simultaneous measurements of HbA1 and fructosamine are also compared with multiple linear regression.


RESULTS
Two hundred eighteen subjects (32%) had 2-h glucose greater than or equal to 11.1 mM, of which only 86 had FPG greater than or equal to 7.8 mM. Only 2 subjects had FPG greater than 7.8 mM and 2-h glucose less than 7.8 mM. Of subjects with 2-h glucose less than 7.8 mM (n = 332), only 9 had FPG greater than 6.0 mM. From the quadratic model, the predicted FPG corresponding to 2-h glucose = 11.1 mM was 5.7 mM, whereas the predicted 2-h glucose corresponding to FPG = 7.8 mM was 15.2 mM. ROC analysis showed that, with 2-h glucose greater than or equal to 11.1 mM as indicating diabetes, an FPG of 5.6 mM gave an intersect for sensitivity and specificity of 87%. HbA1 and fructosamine correlated more closely with 2-h glucose and area under the OGTT curve than with FPG.


CONCLUSIONS
Given that a 2-h glucose cutoff of 11.1 mM can be justified from other studies, our results suggest that the FPG cutoff of 7.8 mM when used for screening purposes should be reduced. At a suggested value of 7.0 mM, specificity remains 98.5%, whereas sensitivity increases to 57%.
Cockram
C S
CS
Department of Medicine, Chinese University of Hong Kong, Shatin.
Lau
J T
JT
Chan
A Y
AY
Woo
J
J
Swaminathan
R
R
D002681:China / Q000208:ethnology; D003920:Diabetes Mellitus / Q000097:blood / Q000175:diagnosis*; D005260:Female; D019270:Fructosamine; D005951:Glucose Tolerance Test; D006442:Glycated Hemoglobin / Q000032:analysis; D006595:Hexosamines / Q000097:blood; D006723:Hong Kong; D006801:Humans; D008297:Male; D008875:Middle Aged; D014944:World Health Organization
D019270:Fructosamine; D006442:Glycated Hemoglobin; D006595:Hexosamines