[Comorbidity characteristics in the different subtypes of attention deficit-hyperactivity disorder]

Cormobidity characteristics in attention deficit-hyperactivity disorder (ADHD) have an important impact on the subjects' behaviour, learning and cognitive development. It has been proposed that certain comorbidity characteristics depend on the ADHD subtype (inattentive vs. hyperactive-impulsive). In this article, a neuropsychological analysis is presented of the comorbidity characteristics in 61 children with an ADHD diagnosis, divided into inattentive versus hyperactive-impulsive. The empirical results support the proposed conceptual division. Moreover, differences between cases with hyperactivity-without-impulsivity and cases with impulsivity with or without hyperactivity were analysed, and the findings revealed some significant differences and a differentiation tendency. The discussion is developed based on Barkley's and Diamond's models. It is concluded that a neuropsychological division reveals certain comorbidity characteristics in ADHD, resulting in a more precise description and the possibility of more specific treatment for each subgroup.