Abstract
Background
Diabetes diagnosis can be made using different laboratory tests, including the fasting plasma glucose (FPG) test, 75-g 2-h oral glucose tolerance test (2-h OGTT), and hemoglobin A1c (HbA1c) test; however, these tests have different meanings. This study aimed at comparing patient characteristics based on the diagnosis using each of these 3 tests.
Methods
A total of 750 adults suspected of having diabetes and aged ≥18 years underwent the following tests on the same day: FPG, 2-h OGTT, HbA1c, insulin, general chemistry, and routine urinalysis. The patients were divided into 8 groups based on the combination of positive and negative results of each of the 3 tests, and the characteristics of the patients were compared among groups.
Results
In the group that tested positive for all 3 tests, the FPG, 2-h OGTT, HbA1c, homeostasis model assessment for insulin resistance, alanine transaminase, triglyceride, and urine glucose positive values were higher than those of the group that tested positive using the 2-h OGTT and HbA1c test. In the group that tested positive using the 2-h OGTT, blood urea nitrogen was higher than that of the group that tested positive using the HbA1c test.
Conclusions
The characteristics of the patients differed between the tests that yielded positive diagnostic results. This may be related to the fact that the 3 tests indicate different states of glucose metabolism. The results of the 3 tests were significantly different; therefore, it may be more effective to combine the results of the 3 tests to comprehensively describe patient characteristics.
Figures and Tables
![]() | Fig. 1Venn diagram shown 8 groups of the patients classified by each results of separate three tests. Group A: All tests are negative. |
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