Abstract
Internalizing disorders and Attention-Deficit/Hyperactivity Disorder (ADHD) co-occur at higher than expected rates and cause significant impairment in youth. The elevated comorbidity may relate to transdiagnostic risk factors that potentially influence symptoms of internalizing symptoms related to anxiety, depression and OCD and could worsen symptoms related to ADHD in a subset of youth with ADHD that are already at risk for emotion regulation difficulties. Preliminary evidence suggests that aspects of emotion dysregulation, including high negative affect and poor tolerance of distress, are elevated in both youth with ADHD and internalizing concerns (Cummings et al., 2013; Okado, Mueller, & Nakamura, 2013). Negative affect and distress intolerance could represent risk factors that promote and exacerbate the co-occurrence of ADHD symptoms such as inattention, hyperactivity and impulsivity with internalizing symptoms in youth.
The present study examined negative affect and distress intolerance as potential moderators in the relationship between ADHD and internalizing disorder symptom severity within a community clinic sample of 199 treatment-seeking adolescents with primary internalizing concerns. Results suggest that these indicators of emotion regulation do not moderate the relationship between ADHD and internalizing symptoms severity. As high negative affect and poor distress tolerance were associated with both internalizing disorders and ADHD independently, it may be that this relationship was obscured within the treatment-seeking, primary internalizing sample of the study. Difficulties with the assessment of ADHD represents another key limitation of this study.