Measurement of Insulin Sensitivity in Children
Comparison between the euglycemic-hyperinsulinemic clamp and surrogate measures
Betsy Schwartz , MD 1 ,
David R. Jacobs, Jr. , PHD 2 ,
Antoinette Moran , MD 1 ,
Julia Steinberger , MD, MS 1 ,
Ching-Ping Hong , MS 2 and
Alan R. Sinaiko , MD 1 2
1 Department of Pediatrics, School of Medicine, University of Minnesota, Minneapolis, Minnesota
2 Division of Epidemiology, School of Public Health, University of Minnesota, Minneapolis, Minnesota
Address correspondence and reprint requests to Alan R. Sinaiko, MD, University of Minnesota Medical School, 420 Delaware St.
SE, MMC 491, Minneapolis, MN 55455. E-mail: sinai001{at}umn.edu
Abstract
OBJECTIVE —In this study we compared fasting insulin and measures of insulin sensitivity ( M ) based on fasting insulin and glucose (i.e., homeostasis model assessment [HOMA], quantitative insulin sensitivity check
index [QUICKI], and fasting glucose–to–insulin ratio [FGIR]) or triglycerides to the insulin clamp in a cohort of children/adolescents.
RESEARCH DESIGN AND METHODS —The subjects were Minneapolis fifth- to eighth-grade students. Euglycemic-hyperinsulinemic clamps were performed on 323 adolescents
at mean age 13 and were repeated on 300 of these subjects at mean age 15. Insulin sensitivity was determined by glucose uptake
(milligrams per kilogram per minute) adjusted for lean body mass ( M LBM ) and steady-state insulin ( M LBM /ln SSI). Comparisons were made for the whole cohort and by body size (BMI <85th percentile vs. BMI ≥85th percentile). Receiver
operating characteristic (ROC) curves were used to test whether specific fasting insulin cut points separated true-positive
from false-positive approximations of insulin resistance.
RESULTS —Fasting insulin was significantly correlated with HOMA ( r = 0.99), QUICKI ( r = 0.79), FGIR ( r = −0.62), and (ln fasting insulin + ln triglycerides) ( r = 0.88). Correlations of the surrogates with M LBM were significantly lower than those with M for the total cohort and ≥85th percentile group. In general, correlations in the ≥85th percentile group were higher than
those in the <85th percentile group. Correlations with M LBM and M LBM /ln SSI decreased in the total cohort and ≥85th percentile group from age 13 to 15. ROC curves showed only a modest capability
to separate true- from false-positive values.
CONCLUSIONS —Surrogate measures are only modestly correlated with the clamp measures of insulin sensitivity and do not offer any advantage
over fasting insulin. In general, lower correlations are seen with M LBM than with M and with thinner than with heavier individuals.
AUC, area under the receiver operating characteristic curve
FGIR, fasting glucose–to–insulin ratio
HOMA, homeostasis model assessment
LBM, lean body mass
QUICKI, quantitative insulin sensitivity check index
ROC, receiver operating characteristic
SSI, steady-state insulin
Footnotes
Published ahead of print at http://care.diabetesjournals.org on 3 January 2008. DOI: 10.2337/dc07-1376.
The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore
be hereby marked “advertisement” in accordance with 18 U.S.C Section 1734 solely to indicate this fact.
Accepted December 20, 2007.
Received July 17, 2007.
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Measurement of Insulin Sensitivity in Children

10.2337/dc07-1376