Learning Disorder Confers Setting-Specific Treatment Resistance for Children with ADHD, Predominantly Inattentive Presentation.

Attention deficit/hyperactivity disorder-predominantly inattentive presentation (ADHD-I) and specific learning disorder (SLD) are commonly co-occurring conditions. Despite the considerable diagnostic overlap, the effect of SLD comorbidity on outcomes of behavioral interventions for ADHD-I remains critically understudied. The current study examines the effect of reading or math SLD comorbidity in 35 children with comorbid ADHD-I+SLD and 39 children with ADHD-I only following a behavioral treatment integrated across home and school (Child Life and Attention Skills [CLAS]). Pre- and posttreatment outcome measures included teacher-rated inattention, organizational deficits, and study skills and parent-rated inattention, organizational deficits, and homework problems. A similar pattern emerged across all teacher-rated measures: Children with ADHD-I and comorbid ADHD-I+SLD did not differ significantly at baseline, but between-group differences were evident following the CLAS intervention. Specifically, children with ADHD-I and comorbid ADHD-I+SLD improved on teacher-rated measures following the CLAS intervention, but children with ADHD-I only experienced greater improvement relative to those with a comorbid SLD. No significant interactions were observed on parent-rated measures-all children improved following the CLAS intervention on parent-rated measures, regardless of SLD status. The current results reveal that children with ADHD-I+SLD comorbidity benefit significantly from multimodal behavioral interventions, although improvements in the school setting are attenuated significantly. A treatment-resistant fraction of inattention was identified only in the SLD group, implying that this fraction is related to SLD and becomes apparent only when behavioral intervention for ADHD is administered.