Abstract 2523: Anthropometric factors and insulin related biomarkers in adolescent girls: Results from the Dietary Intervention Study in Children (DISC).
Authors: Zhang Zhenzhen , Kerver Jean M. , Gardiner Joseph C. , Dorgan Joanne F. , Velie Ellen M. 
Published: August 2014

Abstract
Background: Higher adiposity during childhood has been reported to be associated with reduced breast cancer risk. We hypothesize that adiposity may play a role in later breast cancer development through its influence on the insulin pathway.
Objectives: To prospectively examine associations between baseline childhood adiposity and longitudinal measures of serum insulin related biomarkers (IRBS) (insulin, C-peptide, glucose, homeostasis model assessment of insulin resistance [HOMA]) among girls in the DISC.
Methods: The present study includes 270 of the 301 girls who participated in the DISC (median follow-up: 7 yrs). Among these girls, 224 girls had premenarcheal fasting blood samples and 203 girls had postmenarcheal fasting blood samples collected on at least one of four visits: baseline, years 3, 5 and last visit. Weight, height and waist circumference (WC) were measured at multiple visits. General and central adiposity were assessed as body mass index (BMI)-for-age percentile (BMIPCT) and WC, respectively. Adjusted geometric means of IRBS were calculated within quintiles of baseline BMIPCT and WC. Baseline BMIPCT and WC were also modeled as continuous variables to estimate their associations with longitudinal measures of IRBS, using multivariable linear mixed-effect models. All adjusted analyses included age, age2, treatment group, baseline height, and physical activity.
Results: Premenarcheal girls in the lowest quintile of baseline BMIPCT had the lowest geometric mean of all four IRBS. Both pre- and post-menarcheal girls in the lowest quintile of baseline WC had the lowest geometric mean of insulin, C-peptide and HOMA. Results from continuous analyses of the associations between baseline BMIPCT/WC and IRBS are shown in Table 1.
Conclusion: Results show higher BMIPCT in girls at baseline is associated with higher levels of IRBS premenarche, while higher WC is associated with higher IRBS both pre- and postmenarche.
Table 1. Percent change in concentrations of IRBS based on baseline BMIPCT and WC in adolescent girl % Change (95% CI) per 10% increment in baseline BMIPCT ptrend bmipct % Change (95% CI) per 1cm increment in baseline waist circumference ptrend WC Pre-menarcheal Insulin (uU/mL) 3.9% (2.1%, 5.7%) &lt;0.0001 2.6% (1.6%, 3.6%) &lt;0.0001 C-peptide (pmol/L) 4.2% (1.4%, 7.1%) 0.003 3.1% (1.6%, 4.7%) 0.0001 Glucose (mg/dL) 0.5% (0.007%, 1.1%) 0.05 0.1% (-0.2%, 0.4%) 0.45 HOMA 4.4% (2.4%, 6.5%) &lt;0.0001 2.8% (1.7%, 3.9%) &lt;0.0001 Post-menarcheal Insulin (uU/mL) 1.8% (−0.5%, 4.2%) 0.12 2.0% (0.8%, 3.2%) 0.0009 C-peptide (pmol/L) 0.7% (−1.9%, 3.2%) 0.61 1.5% (0.1%, 2.8%) 0.03 Glucose (mg/dL) −0.1% (−0.5%, 0.3%) 0.55 0.02% (−0.2%, 0.2%) 0.82 HOMA 1.7% (−0.8%, 4.3%) 0.17 2.1% (0.8%, 3.4%) 0.0015
Citation Format: Zhenzhen Zhang, Jean M. Kerver, Joseph C. Gardiner, Joanne F. Dorgan, Ellen M. Velie. Anthropometric factors and insulin related biomarkers in adolescent girls: Results from the Dietary Intervention Study in Children (DISC). [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2523. doi:10.1158/1538-7445.AM2013-2523
Note: This abstract was not presented at the AACR Annual Meeting 2013 because the presenter was unable to attend.