TY - JOUR
T1 - C-peptide suppression test
T2 - Effects of gender, age, and body mass index; implications for the diagnosis of insulinoma
AU - Service, F. J.
AU - O'Brien, P. C.
AU - Kao, P. C.
AU - Young, William Francis
PY - 1992/1
Y1 - 1992/1
N2 - To assess the effects of gender, age, and body mass index (BMI) on suppression of plasma C-peptide during insulin-induced hypoglycemia, 101 lean and obese, healthy men and women ages 20 to 80 yr underwent infusion of human regular insulin, 0.125 U/kg over 60 min after an overnight fast. Plasma glucose, insulin, and C-peptide were measured every 30 min for 120 min. C-peptide concentrations were influenced by gender at 30 min, by BMI at baseline and both BMI and age at all subsequent time points. Because of variations in baseline plasma C-peptide concentrations, percent decrease in C-peptide was evaluated. Significantly less percent decrease of C-peptide with increased age at 30, 60, and 90 min and with increased BMI at 30 and 60 min were noted with no effect of gender. From stepwise regression analysis using multiple, additional variables only the plasma glucose concentration at 30 min made a significant, albeit small (8%), contribution to the variability in percent decrease in C-peptide at 60 min. When C-peptide responses from eight histologically confirmed insulinoma patients were contrasted to values adjusted for age, gender, and BMI of normal subjects, all insulinoma patients had abnormal responses when percent decrease in C-peptide was used, whereas only four insulinoma patients had abnormal response when actual C-peptide concentrations were used.
AB - To assess the effects of gender, age, and body mass index (BMI) on suppression of plasma C-peptide during insulin-induced hypoglycemia, 101 lean and obese, healthy men and women ages 20 to 80 yr underwent infusion of human regular insulin, 0.125 U/kg over 60 min after an overnight fast. Plasma glucose, insulin, and C-peptide were measured every 30 min for 120 min. C-peptide concentrations were influenced by gender at 30 min, by BMI at baseline and both BMI and age at all subsequent time points. Because of variations in baseline plasma C-peptide concentrations, percent decrease in C-peptide was evaluated. Significantly less percent decrease of C-peptide with increased age at 30, 60, and 90 min and with increased BMI at 30 and 60 min were noted with no effect of gender. From stepwise regression analysis using multiple, additional variables only the plasma glucose concentration at 30 min made a significant, albeit small (8%), contribution to the variability in percent decrease in C-peptide at 60 min. When C-peptide responses from eight histologically confirmed insulinoma patients were contrasted to values adjusted for age, gender, and BMI of normal subjects, all insulinoma patients had abnormal responses when percent decrease in C-peptide was used, whereas only four insulinoma patients had abnormal response when actual C-peptide concentrations were used.
UR - http://www.scopus.com/inward/record.url?scp=0026608877&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0026608877&partnerID=8YFLogxK
M3 - Article
C2 - 1727822
AN - SCOPUS:0026608877
VL - 74
SP - 204
EP - 210
JO - Journal of Clinical Endocrinology and Metabolism
JF - Journal of Clinical Endocrinology and Metabolism
SN - 0021-972X
IS - 1
ER -