The role of physical activity in the association between ADHD and emotional dysregulation

Background: Emotional dysregulation (ED) represents a burden for individuals with ADHD. Physical activity (PA) is associated with improvements in emotion regulation, but knowledge is limited regarding its role in ED in the context of ADHD. This study aimed to increase understanding of the association between ADHD and ED and to explore the role of PA. Identifying modifiable risk factors could aid the design of future interventions. Methods: Children from the Swedish Twin Registry were included. ADHD symptoms and PA intensity and frequency were measured using parent-reported questionnaires at age 9/age 12. ED was assessed through questionnaires at age 15. The association between ADHD and ED was assessed through linear GEE regression models. Interaction terms and stratified analyses by level of PA were used to explore the role of PA. Analyses were done separately for boys and girls. Results: 12,094 children (52 % girls) were included. A positive association between ADHD symptoms and ED remained significant after adjusting for mental comorbidities and unmeasured family-shared confounders ((3 = 0.07, 95% CI 0.02-0.12 in boys; (3 = 0.09, 95% CI 0.02-0.16 in girls). The association was driven by inattention in boys but combined symptoms in girls. The association remained in all strata of PA. A significant interaction between PA frequency and ADHD symptoms was observed among boys (p = 0.02). Limitations: Results were based on parent-reported PA; findings might differ with sensor-based measurements. Conclusion: Higher ADHD symptoms in childhood were associated with greater ED in adolescence in all PA levels. Low PA frequency intensified the association among boys.