Persistent Aggressive Behaviour From Childhood to Adolescence: The Influence of Environmental Tobacco Exposure and the Protective Role of Fish Consumption

Background: Understanding changes in aggressive behaviour throughout child development is crucial for identifying effective intervention strategies. This study investigates children's aggressive behaviour in a longitudinal cohort and explores the role of environmental tobacco exposure and fish consumption as potential risk and protective factors, respectively, for persistent aggression in children.

Methods: This study involved 452 children from the Chinese Jintan Cohort. Aggressive behaviour was assessed at ages 6 and 12 years using the child behaviour checklist (CBCL) and the Reactive-Proactive Aggression Questionnaire (RPQ), respectively. Information on lifestyle habits and living environment, including parental smoking, was collected via questionnaires. Linear regression was employed to investigate the association between childhood and adolescence aggressive behaviour with relevant covariates adjusted. Subsequently, we conducted interaction analyses to explore the moderating effects of parent smoking and fish consumption on the association.

Results: We identified no significant association between childhood and adolescent aggression in the entire sample. Interaction analysis revealed environmental tobacco exposure as a moderator for the association. Specifically, persistent reactive and total aggression across development was only observed among those with environmental tobacco exposure (reactive: β = 0.549, p = 0.020; total: β = 0.654, p = 0.035). Furthermore, within the parent smoking subgroup, freshwater fish consumption at the age of 12 showed a marginally significant interaction with childhood aggression (reactive: p = 0.061; total: p = 0.095). A significant longitudinal association for aggression was found only among those consuming fish less frequently at the age of 12 years (reactive: β = 0.927, p = 0.002; total: β = 1.082, p = 0.006).

Conclusion: Our findings suggest exposure to environmental tobacco as a contributing factor to the lasting presence of aggressive behaviour during children's development, whereas freshwater fish consumption shows potential protective effects.