Adolescent eating behaviours: associations with autistic and ADHD traits in childhood and the mediating role of anxiety.

BACKGROUND

Autistic individuals and individuals with ADHD are more likely to experience eating disorders, yet the reasons for this are not well understood. We investigated whether childhood neurodivergent (i.e. autistic and ADHD) traits are associated with patterns of emotional/restrained eating and externally driven eating behaviours in adolescence, whether these associations differed by sex and if they are mediated by anxiety.

METHODS

We tested the association between parent-reported childhood (age 7 years) autistic and ADHD (i.e. hyperactivity/impulsivity, inattention) traits and self-reported adolescent (age 13) eating behaviours in a large population-representative prospective cohort (N = 7,572; Avon Longitudinal Study of Parents and Children). We performed multi-group longitudinal analysis stratified by sex to understand whether sex moderates' associations between neurodevelopmental traits and adolescent eating behaviours. Mediation models tested the extent to which observed associations were driven by mid-childhood (age 10) anxiety symptoms. All analyses were adjusted for child sex, child ethnicity, maternal education levels and maternal age at birth.

RESULTS

Individuals who had higher childhood autistic traits were more likely to report emotional/restrained (b = 0.59, 95% CI [0.29, 0.88], p < .001, B = 0.07) and externally driven (b = 0.17, 95% CI [0.05, 0.28], p < .01, B = 0.06) eating behaviours during adolescence. Additionally, individuals with higher childhood inattention traits were more likely to report externally driven eating behaviours (b = 0.10, 95% CI [0.03, 0.19], p = .02, B = 0.05). No sex differences were identified in the associations. Mediation models suggested a significant indirect effect of anxiety for the association between autistic traits and emotional/restrained eating (b = 0.08, bootstrapped 95% CIs [0.02, 0.13]).

CONCLUSIONS

Autistic and ADHD traits in childhood may share some eating behaviour phenotypes in adolescence (externally driven eating), whereas others are specific to autism (emotional/restrained eating). We present evidence for the role of anxiety in underpinning the association between autistic traits and emotional/restrained eating behaviours, suggesting an important potential intervention target.