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

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 mainlyindependent 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.