Reactivity and regulation of negative and positive emotions in child- and adolescent diagnostic and trait-level ADHD: a cross-sectional study

Emotional difficulties are common in attention-deficit/hyperactivity disorder (ADHD), but previous research lack specificity regarding how reactivity and regulation of distinct emotions relate to categorical (diagnostic) and dimensional (trait-level) ADHD, while also clarifying sex- and age-related patterns. Considering co-occurring psychiatric traits is important due to the transdiagnostic nature of emotional challenges. This cross-sectional study included two samples: a diagnostic cohort (N = 104, 10–17 years, 56.7% females) consisting of participants with an ADHD diagnosis (n = 56) and typically developing controls (n = 48), and a cohort referred to a first visit to a specialist psychiatric unit (N = 85, 13–18 years, 78.8% females) for which a dimensional measure of ADHD was used. Linear regressions were used to assess associations between ADHD and self- and caregiver-rated reactivity (frequency/intensity) and regulation (by oneself or with the help of others) of four different emotions (sadness, fear, anger and exuberance) using the Emotion Questionnaire. Effects of sex were explored. Adjustments were made for age and co-occurring psychiatric traits (anxiety, depression, conduct problems and autism) within the referred cohort. Findings were validated through caregiver ratings for the diagnostic cohort (N=103) and the referred cohort (N=212). Diagnostic and trait-level ADHD were robustly linked to reactivity and a limited ability to regulate (i.e., dysregulation) anger. Diagnostic ADHD was also related to dysregulation of exuberance and fear, and higher levels of sadness and fear reactivity. Trait-level ADHD was, in addition to anger, associated with elevated reactivity and dysregulation of exuberance, adjusting for co-occurring psychiatric symptoms. No interaction effects of sex by ADHD were identified. Anger may be particularly relevant for ADHD. Reactivity and dysregulation of exuberance may also be important for ADHD, although further research is needed to clarify the relation between ADHD and positive emotions. Potential effects of sex and co-occurring psychiatric traits are discussed.