J Korean Diabetes Assoc.  2000 Jun;24(3):385-392.

Evaluation of 25% and 50% -75 gm Oral Glucose Tolerance Test - Animal and Clinical Pilot Study: Emphasis on Glucose Kinetics and Preference Evaluation

• Cho NH
• Hong EG

Abstract

BACKGROUND: Oral glucose tolerance test to diagnose diabetes was first introduced by Jarney and Isaacson in 1918. This method was advocated because of its diagnostic accuracy and also provides the two hours glucose changing pattern. Twenty-five percent (296 mL) glucose solution has been used as the standard diagnostic method in Korea. However, large volume of the solution frequently cause vomiting during the tests. Thus, 50% solution (150 mL) was recently introduced, but the potential difficulty of gastric emptying caused by its hyperosmolarity, and degree of diagnostic accuracy was questioned. Therefore, in this study, we evaluated two type of solutions by comparing the followings in both an animal and human models: (1) glucose changing pattern during the two hour oral glucose tolerance test, (2) Preference evaluation in human model.
METHODS
Fifteen male Sprague-Dawley rats and 15 human subjects underwent 2 hours OGTT after 10~14 hours fasting. Two grams glucose per kg body weight was feed to the SD rat. In human, 75 gm glucose in 296 mL (25%) and 150 mL (50%) glucose solution was ingested at two different time, but testing was done within 24 hours a part. Five blood samples (fasting, 30, 60, 90, and 120 minutes) were collected and separated for serum. Glucose was assayed using YSI 2300-STAT (Yellow Springs Instrument Co., Ohio, USA) by glucose oxidase method.
RESULTS
In animal study, despite the lower fasting glucose level, 30, 60 and 120 minutes glucose level was higher in 50% solution when compared to the 25% but the mean values were not statistically different. The glucose area under the curve (GAUC) in 50% was higher than 25% but not statistically different. The peak glucose level was observed at 60 minutes in both solutions. In human study, although mean values were not statistically different, all glucose values except 30 minutes were higher in 50% solution. Furthermore, GAUC was not statistically different between the two solutions. In preference test, the study subjects significantly (p<0.05) preferred the 50% solution as more favorable amount for the test. No differences in the tolerable level of sweetness, level of thirsty after ingestion, nausea, vomiting, head and stomachache was observed.
CONCLUSION
In this study, we found that the gastro-intestinal glucose kinetics of the 25% and 50% glucose solution used during the OGTT was very similar in both an animal and human model. Furthermore, the preference evaluation showed favorable results in 50% solution. The use of 50% solution reconcile vomiting problem during the test but the same diagnostic accuracy was preserved. Therefore, 50% solution merits its scientific value as the diagnostic solution, and hope to contribute to favor the OGTT for diagnosis of diabetes mellitus in the future.

Keyword

OGTT; 25 and 50% Glucose; Glucose kinetics; Preference Evaluation

MeSH Terms

Animals
Body Weight
Diabetes Mellitus
Diagnosis
Eating
Fasting
Gastric Emptying
Glucose Oxidase
Glucose Tolerance Test*
Glucose*
Head
Hope
Humans
Kinetics*
Korea
Male
Nausea
Ohio
Pilot Projects*
Rats
Rats, Sprague-Dawley
Vomiting
Glucose
Glucose Oxidase