Glucose tolerance tests and their insulin and growth hormone responses in hemodialysis patients: are they reproducible?
The concept that carbohydrate intolerance improves after hemodialysis has been challenged. Critical to this issue is the reproducibility of GTT in a dialysis population. Thirty-nine oral or i.v. GTT were performed on ten stable hemodialysis patients at weekly intervals for three weeks. Blood glucose was determined by both oxygen consumption rate during glucose oxidation and the ferricyanide method. The coefficient of variation of blood glucose ratios (Glucose at time X/Fasting glucose) by glucose oxidase varied considerably. With the i.v. GTT the coefficients of variation at 90 and 120 minutes were 27.9 and 36.8 percent in one patient but below 15 percent at 60, 90, and 120 minutes in the other four patients. Three of the five patients who received oral GTT displayed coefficients of variation greater than 20 percent at one or more sampling times. The coefficients of variation of the growth hormone ratio (Growth hormone at time X/Fasting growth hormone) during i.v. and oral GTT ranged from 2.1 to 83.6 percent. Coefficients of variation of insulinogenic indexes ranged from 16.3 to 59.3 percent. In summary, large variations in glucose, growth hormone and insulin occur during both oral and i.v. GTT when repeated on a weekly basis in stable hemodialysis patients.
D000284:Administration, Oral; D005069:Evaluation Studies as Topic; D005260:Female; D005947:Glucose / Q000008:administration & dosage; D005951:Glucose Tolerance Test; D013006:Growth Hormone / Q000097:blood*; D006801:Humans; D007275:Injections, Intravenous; D007328:Insulin / Q000097:blood*; D008297:Male; D006435:Renal Dialysis
D007328:Insulin; D013006:Growth Hormone; D005947:Glucose