Abstract MP35: Hair Cortisol Concentrations Are Associated With Greater Adiposity in Mid-Adolescence

Abstract

Introduction: Hair cortisol concentration (HCC) is a biomarker of long-term stress. Higher HCC is associated with body mass index (BMI) and other adiposity measures in adults; however, this association is not well characterized in adolescents. Additionally, HCC differs by sex, but associations with adiposity by sex have not been well studied. Hypothesis: Higher HCC levels are associated with greater adiposity in mid-adolescence. Methods: Among 324 participants (49.1% female, mean 17.7 years) in Project Viva, we performed a cross-sectional analysis of HCC with measures of adiposity in mid-adolescence. We used multivariable linear regression models, overall and stratified by sex, to estimate associations of HCC (log2 transformed) with BMI, % body fat, and waist circumference (WC), adjusted for age and known predictors of adiposity, namely maternal education, smoking during pregnancy, pre-pregnancy BMI, age, and household income; and child sex-specific birthweight for gestational age z-scores, secondhand smoke exposure, age, and sex (for overall models). Results: Median (IQR) HCC was 2.1 pm/mg (1.0 – 4.7) and mean (SD) BMI was 23.0 kg/m 2 (3.8), % body fat was 20.1% (9.9), and WC was 80.4 cm (10.8). In adjusted models, HCC (per doubling) was associated with higher BMI (β 0.20 kg/m 2 ; 95% CI 0.01, 0.39), % body fat (β 0.42%; 95% CI 0.04, 0.80), and WC (β 0.45 cm; 95% CI -0.07, 0.96) (Figure). There was no evidence of effect modification by sex (all sex by HCC interaction p-values >0.50). Conclusions: Higher HCC was cross-sectionally associated with greater adiposity in mid-adolescence. Associations were similar among males and females, suggesting a similar impact of long-term stress on adiposity between sexes. Adjustment for known predictors of adiposity does not alter the association of HCC and adiposity measures. Further research is needed to understand the temporal direction of this association.