Autism and attention-deficit/hyperactivity disorders and symptoms in children with neurofibromatosis type 1.

Diagnoses of attention-deficit/hyperactivity disorder (ADHD) were more common in children with neurofibromatosis type 1 (NF1) than in the general child population. Diagnoses of autism spectrum disorder were no more common in children with NF1 than in the general child population. Increases in autism symptoms did not reach clinically significant thresholds. Co-occurring ADHD symptoms accounted for increased autism questionnaire scores. Adaptive behavior in participants with NF1 showed normal socialization but lower communication proficiency.