Does fasting interval affect the glucose challenge test?
The relationship between fasting interval and glucose screening was assessed in a prospective study of 153 non-diabetic pregnant patients undergoing a standard 50g glucose challenge test. An interval of less than 3 hours after the last meal was found to be associated with a significantly greater insulin response as opposed to a fasting interval of more than 3 hours (121.3 pmol/l vs. 83.5 pmol/l, p less than .001) and a greater insulin/glucose index (0.92 vs. 0.66, p less than .001), with no difference in plasma glucose. Overall, obese patients had a higher glucose response than non-obese, but only higher insulin levels (107 pmol/l vs. 69 pmol/l, p less than .001) and insulin/glucose index (0.79 vs. 0.59, p less than .02) when the fasting interval was greater than 3 hours. Our data suggest that the fasting interval can influence insulin response during a glucose challenge test and the aberration in insulin secretion may effect screening results, especially in the high-risk gravida with glucose abnormality.
Berkus
M D
MD
Department of Obstetrics and Gynecology, University of Texas Health Science Center, San Antonio 78284-7836.
Stern
M P
MP
Mitchell
B D
BD
Newton
E R
ER
Langer
O
O
D000328:Adult; D000704:Analysis of Variance; D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D016009:Chi-Square Distribution; D005215:Fasting / Q000097:blood*; D005260:Female; D005951:Glucose Tolerance Test / Q000379:methods; D006801:Humans; D007328:Insulin / Q000097:blood; D015999:Multivariate Analysis; D009765:Obesity / Q000097:blood; D011247:Pregnancy; D011248:Pregnancy Complications / Q000097:blood; D011254:Pregnancy in Diabetics / Q000097:blood / Q000175:diagnosis; D011446:Prospective Studies; D011817:Rabbits; D013997:Time Factors
D001786:Blood Glucose; D007328:Insulin