Abstract P127: Early Life Adversity and Obesity Risk in Adolescence: A 9-year Population-Based Prospective Cohort Study

Abstract

Objective: We previously found that exposure to adverse childhood experiences (ACEs) is associated adolescent obesity. This study was designed to identify mediators of this association. We hypothesized that exposure to adverse experiences before 9 yrs would be associated with an increased risk of obesity at 18 yrs, and that behavioural and emotional factors would mediate this association. Methods: In 2007/2008, 8568 nine-year-olds were randomly sampled, enrolled in the Growing up in Ireland cohort study and followed in 18 yrs. The main exposures were 14 adverse experiences including four of the traditional ACEs before 9 years of age, self-reported by the primary care giver. The main outcome, body mass index (BMI) was measured objectively at 18 yrs. Mediators were self-reported daily activity, soda intake, self-image (Piers Harris) and behavioural difficulties (Strengths and Difficulties Questionnaire) at 9 and 13 yrs. Co-variates were household income and primary caregiver BMI. Structural equation models (SEMs) tested for mediators of the association between exposure to adverse experiences and ACEs before 9 yrs and BMI at 18 yrs. Results: Among the 6039 adolescents with complete data, 76% experienced any adversity, 14% experienced an ACE, 49% were female and 27% were overweight/obese at 18 yrs. BMI Z score was higher at ages 9 (0.47 vs 0.36, p < 0.05) and 13 yrs ( 0.39 vs 0.29, p < 0.05) in those exposed to an adverse experience or an ACE, compared to those unexposed. Behavioural difficulties were higher and self image was lower at all three time points for those exposed to any adversity or an ACE, compared to those unexposed. SEMs revealed that behavioural difficulties and self concept, but not exercise or soda intake, modestly mediate the association between exposure to adverse experiences and BMI at 18 years (Figure 1). Conclusion: Exposure to any adversity or ACEs are not directly associated BMI at 18 yrs. Behavioural difficulties and self-concept weakly mediate the association between adverse childhood experiences and BMI at 18yrs.