Functional somatic symptoms in preschool attention-deficit/hyperactivity disorder: a secondary analysis of data from a randomized controlled trial of parent training

Children with attention-deficit/hyperactivity disorder (ADHD) can be more stress-vulnerable, and thereby, it has been suggested, prone to develop functional somatic symptoms (FSS) compared to their peers. In this paper, using data from 160 children aged 3–7 years with ADHD from the D’SNAPP study, a randomized controlled trial testing a parent training intervention, we addressed a number of questions about the role of FSS in ADHD. First, are FSS levels higher in an ADHD sample than in the children of the general population. Second, do FSS levels predict psychopathology and health-related quality of life (HRQoL) in ADHD samples. Third, does FSS levels moderate the effect of parent training on ADHD symptoms. We found that preschoolers with ADHD experienced more severe FSS than a general population-based sample (18.80% vs. 2.11%). Severe FSS were associated with increased psychopathology and impaired daily function and lower HRQoL. Level of baseline FSS did not moderate the effect of parent training on ADHD. FSS in preschool children with ADHD is associated with impaired daily functioning, but further research is warranted to determine the clinical impact of FSS in children with ADHD.