Autism and attention-deficit/hyperactivity disorder in children with cerebral palsy: high prevalence rates in a population-based study

Magnus Påhlman , Christopher Gillberg , Kate Himmelmann

Abstract

Aim: To assess a total population of school-age children with cerebral palsy (CP) for autism and attention-deficit/hyperactivity disorder (ADHD) with a view to determining their prevalence and to relate findings to motor function, intellectual disability, and other associated impairments.

Method: Of 264 children, born between 1999 and 2006, from the CP register of western Sweden, 200 children (109 males, 91 females, median age at assessment 14y, range 7-18y) completed comprehensive screening and further neuropsychiatric clinical assessments.

Results: Ninety children (45%) were diagnosed with autism, ADHD, or both, 59 (30%) were diagnosed with autism, and 60 (30%) were diagnosed with ADHD. Intellectual disability was present in 51%. Two-thirds had autism, ADHD, and/or intellectual disability. In regression models, autism was mainly predicted by intellectual disability (odds ratio [OR]=4.1) and ADHD (OR=3.2), and ADHD was predicted by intellectual disability (OR=2.3) and autism (OR=3.0). Autism was more common in children born preterm (OR=2.0). Gross motor function was not associated with autism. ADHD prevalence was low in children with severe motor impairment, possibly due to diagnostic limitations.

Interpretation: Autism and ADHD were common in this population of children with CP and were mainly independent of motor severity and CP type. The strongest predictor of autism/ADHD was intellectual disability. Assessment for autism and ADHD is warranted as part of the evaluation in CP.

What this paper adds: Forty-five percent of the children with cerebral palsy also had autism, attention-deficit/hyperactivity disorder (ADHD), or both. Autism and ADHD were predicted mainly by intellectual disability. Established diagnostic instruments worked well for all but the most disabled group of children.