Exposure to Early Life Stress, Stress Regulation, and Obesity Trajectories from Age 2 to 12 Years

• In Event: 3-011 - Multi-Faceted Risk Exposure and Outcomes Through Early Adolescence: Transdisciplinary Findings from the Family Life Project

Integrative Statement

Introduction: Exposure to stress in early childhood has been linked to development of biological dysregulation, including obesity. Cortisol is the most widely used stress biomarker, and is associated with the accumulation of abdominal fat in children, adolescents and adults. This paper will examine links between children’s exposure to household stress in early life, stress regulation and obesity trajectories through early and middle childhood.

Hypotheses: Children exposed to higher levels of household stress will exhibit stress dysregulation (as indexed by poorer cortisol recovery post-stress) and higher obesity over time.

Study Population: Participants included almost 900 predominantly rural, poor children and their mothers recruited from the Family Life Project, a longitudinal study on children’s development from birth through adolescence.

Methods: Age- and sex-specific BMI indices were calculated from measured height and weight at 8 timepoints between ages 2 and 12 years. Latent growth curve modeling was used to create obesity trajectories; models were run separately for boys and girls. Three saliva samples were collected in response to a frustration task when children were 15 and 24 months. Area under the curve and cortisol recovery post-stress was calculated. Early life exposure to stress was measured at 24 and 36 months, and included having a harsh/insensitive parent, household disorganization, and exposure to a parent with depression.

Results: For both sexes, three trajectories of obesity emerged; a group that maintained normal weight over time, a group that became obese, and a group that became severely obese. Boys in the severe obesity group exhibited significantly poorer cortisol recovery than those in the obesity or normal weight group. For girls, the greatest cortisol output was evident in the group that became obese, while the lowest output was evident in the group that became severely obese. Girls in the normal weight group and the severely obese group exhibited the poorest recovery post stress. Associations with household stressors will be discussed.

Conclusions: To the extent that cortisol recovery and output following exposure to stress is a marker for children’s biobehavioral regulation, results from this study provide some evidence for links between regulatory processes across domains of development, namely stress (adrenocortical) regulation and adiposity (body weight regulation).

Authors

• Lori Anne Francis, The Pennsylvania State University
  Presenting Author

• Brandi Rollins, The Pennsylvania State University
  Non-Presenting Author

• Clancy Blair, New York University
  Non-Presenting Author