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overweight ( bmi 85th percentile for age and sex ) but otherwise healthy youth , 71 african american and 80 caucasian ( aged 817 years ) , underwent assessment of glucose tolerance at the pediatric clinical and translational research center at children 's hospital of pittsburgh .
body composition was measured by dual - energy x - ray absorptiometry ( dexa ; lunar , madison , wi ) .
plasma glucose , insulin , lipid profile , adiponectin , leptin , and the nontraditional cvd risk markers intracellular adhesion molecule-1 , vascular cell adhesion molecule-1 , and e - selectin were measured as described previously ( 911 ) .
proinsulin , fibrinogen , and high - sensitivity c - reactive protein ( hs - crp ) were measured at the esoterix endocrinology laboratory ( calabasas hills , ca ) . for hs - crp ,
values > 10 mg / l were excluded because they may be a sign of occult infection or other systemic inflammatory process ( 10 of 151 participants ) ( 12 ) .
data are presented as means  sd for normally distributed continuous variables , median ( interquartile range ) for non - normal continuous variables , and n ( % ) for categorical variables .
independent student t tests were used to compare normally distributed continuous subject characteristics , and pearson  test was used to compare proportions .
the study population was categorized according to quartiles of fasting and 2-h glucose and insulin levels to assess differences between the quartiles in cvd risk factors .
ancova , adjusted for age , sex , race , tanner stage ( prepubertal and pubertal ) , and percent body fat ( measured by dexa ) , was used to compare metabolic variables between the quartiles of glucose and insulin groups .
all statistical tests were two - tailed , and p values of 0.05 were considered to be statistically significant .
plasma glucose , insulin , lipid profile , adiponectin , leptin , and the nontraditional cvd risk markers intracellular adhesion molecule-1 , vascular cell adhesion molecule-1 , and e - selectin were measured as described previously ( 911 ) .
proinsulin , fibrinogen , and high - sensitivity c - reactive protein ( hs - crp ) were measured at the esoterix endocrinology laboratory ( calabasas hills , ca ) . for hs - crp ,
values > 10 mg / l were excluded because they may be a sign of occult infection or other systemic inflammatory process ( 10 of 151 participants ) ( 12 ) .
data are presented as means  sd for normally distributed continuous variables , median ( interquartile range ) for non - normal continuous variables , and n ( % ) for categorical variables .
independent student t tests were used to compare normally distributed continuous subject characteristics , and pearson  test was used to compare proportions .
the study population was categorized according to quartiles of fasting and 2-h glucose and insulin levels to assess differences between the quartiles in cvd risk factors .
ancova , adjusted for age , sex , race , tanner stage ( prepubertal and pubertal ) , and percent body fat ( measured by dexa ) , was used to compare metabolic variables between the quartiles of glucose and insulin groups .
all statistical tests were two - tailed , and p values of 0.05 were considered to be statistically significant .
of the 151 subjects , 71 were african american ( 59% female , 41% male ; mean age 12.3  2 years ; tanner stage 22.9% prepubertal , 77.1% pubertal ; mean bmi 32.1  5.8 kg / m ; bmi percentile 98.2  2.0 ; percent body fat 43.2  7.5% ) and 80 were caucasian ( 54% female , 46% male ; mean age 13.1  2.6 years ; tanner stage 21.9% prepubertal , 78.8% pubertal ; mean bmi 33.0  6.8
kg / m ; bmi percentile 98.4.2  1.6 ; percent body fat 43.8  6.1% ) .
there were no significant associations between quartiles of glucose levels , either fasting ( mean glucose 77  4 , 85  1 , 90  1 , and 94  2 mg / dl , respectively , in the lowest , 2nd , 3rd , and highest quartiles ) or at 2 h ( mean glucose 94  7 , 108  3 , 118  3 , and 129  4 mg / dl , respectively , in the lowest , 2nd , 3rd , and highest quartiles ) , with any of the cvd risk factors ( p for trend > 0.05 ) after adjusting for age , sex , race , tanner stage , and percent body fat .
the median ( interquartile range ) values for fasting insulin levels was 13.7 ( 12.015.3 ) , 21.0 ( 18.422.0 ) , 28.7 ( 26.230.7 ) , and 43.8 ( 37.853.7 ) iu / ml for quartiles 1 , 2 , 3 , and 4 , respectively . for 2-h insulin levels
the values were 48.1 ( 30.752.9 ) , 76.4 ( 69.184.2 ) , 125.4 ( 107.0155.4 ) , and 222.8 ( 202.0300.0 ) iu / ml for quartiles 1 , 2 , 3 , and 4 , respectively .
quartiles of insulin , fasting and at 2 h , were associated with heightened cvd risk factors .
systolic and diastolic blood pressure , triglycerides , vldl cholesterol , intracellular adhesion molecule-1 , and leptin increased significantly with increasing fasting insulin ; triglycerides , vldl - cholesterol , and leptin increased with increasing 2-h insulin .
hdl cholesterol decreased with increasing quartiles of fasting insulin ( 44  12 , 42  9 , 40  7 , 39  9 mg / dl for quartiles < 25 , 25<50 , 50<75 and 75 , respectively ; p for trend = 0.04 ) cvd risk markers according to fasting and 2-h insulin quartiles .
dbp , diastolic blood pressure ; icam , intracellular adhesion molecule-1 ; sbp , systolic blood pressure .
our findings in overweight nondiabetic children demonstrate that 1 ) an increase in insulin quartiles , fasting and at 2 h , was associated with higher levels of a number of cvd risk factors ; and 2 ) glucose quartiles were not associated with increased risk factors for cvd . with childhood obesity reaching epidemic proportions , there is a need to determine the best marker for early identification of cvd morbidity in this population . in our study ,
quartiles of glucose , both fasting and at 2 h , were not associated with heightened risk factors for cvd .
it is arguable that , in children , glucose levels may need to be in the impaired fasting glucose or impaired glucose tolerance range in order to begin to observe a relationship with cvd risk factors .
insulin levels have also been described to play a significant role with regard to risk for cvd . in our study , increases in insulin quartiles , fasting and at 2 h ,
it has been postulated that diabetes and cvd may share an underlying cause , a theory known as the  common soil  hypothesis ( 1314 ) .
insulin resistance has been proposed as central to both progression to type 2 diabetes and cvd . our data ,
although cross - sectional , suggest that hyperinsulinemia may well be the first and earlier abnormality that presents in children at risk .
we could speculate that this may lead to an increase in cvd risk factors and , with time , to glucose dysregulation .
prospective studies are needed , and interventions should be initiated early in life in overweight at - risk youths .
objectiveto determine whether elevated fasting or 2-h plasma glucose and/or insulin better reflects the presence of cardiovascular disease ( cvd ) risk markers in an overweight pediatric population with normal glucose tolerance.research design and methodsa total of 151 overweight youths ( 817 years old ) were evaluated with oral glucose tolerance tests and measurement of cvd risk factors . 
 the study population was categorized according to quartiles of fasting and 2-h glucose and insulin levels . 
 ancova , adjusted for age , sex , race , tanner stage , and percent body fat ( measured by dual - energy x - ray absorptiometry ) , was used to compare metabolic variables between the quartiles of glucose and insulin groups.resultsincreasing quartiles of fasting and 2-h insulin were associated with increasing cvd risk factors . 
 glucose quartiles on the other hand , either fasting or at 2 h , were not.conclusionsthese data suggest that hyperinsulinemia may be the earliest and/or primary metabolic alteration in childhood associated with risk markers for cvd . 
 prospective studies are needed .