Low-income children are significantly more likely to be obese, experience chronic stress, and have difficulty self-regulating their emotions and behavior in response to stress. Socioeconomic disparities in obesity begin in early childhood and track throughout the lifespan, but the etiology of such differences is unclear. One way that stress is hypothesized to """"""""get under the skin"""""""" is via changes in the hypothalamic-pituitary-adrenal (HPA), or """"""""stress"""""""" axis and patterns of cortisol secretion. Under conditions of chronic stress, such as poverty, aberrations in both the normal diurnal pattern of cortisol secretion and cortisol reactivity to stress occur. Obese, compared to non-obese, adults often show such aberrations. Young children living in poverty can also often demonstrate aberrant patterns of cortisol secretion in response to stress;yet, no study has examined links between stress, cortisol, self-regulation, and obesity in low-income children. Studying how the cycle of poverty, stress, and obesity begins early in life is vital, because once established, obesity typically persists. We propose to build on our existing Challenge Grant parent study of diurnal cortisol patterns, eating behavior and obesity in Head Start children (NIH 1RC1DK086376-01, Cortisol and Eating Behavior in Low-Income Preschool-Aged Children, Principal Investigator Lumeng) to investigate associations between poor emotional and behavioral self-regulation and increased obesity risk. We will specifically examine aberrant patterns of cortisol reactivity to stress as a mediator of such associations in this unique cohort of young, low-income children. We are an interdisciplinary team that studies biologic, psychological, and behavioral processes in order to examine the complex relationships among stress, cortisol, self-regulation, and obesity. Improved understanding of associations between self-regulation and obesity in low-income preschool-aged children will provide new points for targeted obesity prevention and intervention programs for young children that focus on self-regulatory skills. Structural equation modeling will be used to examine potential associations.
Specific aims are, among 250 low-income 3- to 5-year old children:
Aim 1 : Examine the association between self-regulation and child body mass index (BMI) z-score.
Aim 2 : Examine the association between patterns of cortisol reactivity to stress and child BMI z-score.
Aim 3 : Examine cortisol stress reactivity patterns as a mediator of the association between self-regulation and child BMI z-score.
Aim 4 : Examine change in BMI z-score (over 18 months) in relation to these variables, and to predictors from our Challenge Grant parent study (e.g., diurnal salivary cortisol pattern, comfort food intake, emotional eating). Study results will have implications for understanding mechanisms of self-regulation, stress, cortisol, and obesity in young children in relation to the early emergence of health disparities.

Public Health Relevance

Socioeconomic disparities in obesity begin in early childhood and track throughout the lifespan, but the etiology of such differences is unclear. Aberrations in the hypothalamic-pituitary-adrenal (HPA), or """"""""stress"""""""" axis, and cortisol production in response to stress is suggested as one way for stress to """"""""get under the skin"""""""" and lead to adverse health outcomes such as obesity in chronically stressed, impoverished populations. Altered cortisol patterns are also seen in children with emotional and behavioral self-regulation difficulties. We will examine associations between poor self-regulation and increased obesity risk, and test whether cortisol reactivity to stress mediates such associations, in a sample of 250 low-income preschool-aged children. Results have implications for understanding mechanisms of self-regulation, stress, and obesity in young children, and how early health disparities may arise.

Agency
National Institute of Health (NIH)
Institute
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Type
Exploratory/Developmental Grants (R21)
Project #
5R21DK090718-02
Application #
8144764
Study Section
Special Emphasis Panel (ZRG1-PSE-H (80))
Program Officer
Horlick, Mary
Project Start
2010-09-20
Project End
2013-08-31
Budget Start
2011-09-01
Budget End
2013-08-31
Support Year
2
Fiscal Year
2011
Total Cost
$230,918
Indirect Cost
Name
University of Michigan Ann Arbor
Department
Other Health Professions
Type
Other Domestic Higher Education
DUNS #
073133571
City
Ann Arbor
State
MI
Country
United States
Zip Code
48109
Domoff, Sarah E; Lumeng, Julie C; Kaciroti, Niko et al. (2017) Early Childhood Risk Factors for Mealtime TV Exposure and Engagement in Low-Income Families. Acad Pediatr 17:411-415
Fernandez, Carmen; Kasper, Nicole M; Miller, Alison L et al. (2016) Association of Dietary Variety and Diversity With Body Mass Index in US Preschool Children. Pediatrics 137:e20152307
Leung, C Y Y; Miller, A L; Kaciroti, N A et al. (2016) Low-income pre-schoolers with higher temperamental surgency enjoy and respond more to food, mediating the path to higher body mass index. Pediatr Obes 11:181-6
Miller, Alison L; Sturza, Julie; Rosenblum, Katherine et al. (2015) Salivary alpha amylase diurnal pattern and stress response are associated with body mass index in low-income preschool-aged children. Psychoneuroendocrinology 53:40-8
Miller, Alison L; Lee, Hannah J; Lumeng, Julie C (2015) Obesity-associated biomarkers and executive function in children. Pediatr Res 77:143-7
Miller, Alison L; Lumeng, Julie C; LeBourgeois, Monique K (2015) Sleep patterns and obesity in childhood. Curr Opin Endocrinol Diabetes Obes 22:41-7
Elhassan, Maha E; Miller, Alison L; Vazquez, Delia M et al. (2015) Associations of Prenatal and Perinatal Factors with Cortisol Diurnal Pattern and Reactivity to Stress at Preschool Age Among Children Living in Poverty. J Clin Res Pediatr Endocrinol 7:114-20
Miller, Alison L; Kaciroti, Niko; Lebourgeois, Monique K et al. (2014) Sleep timing moderates the concurrent sleep duration-body mass index association in low-income preschool-age children. Acad Pediatr 14:207-13
Miller, Alison L; Clifford, Caitlin; Sturza, Julie et al. (2013) Blunted cortisol response to stress is associated with higher body mass index in low-income preschool-aged children. Psychoneuroendocrinology 38:2611-7