DSM-IV Disorders in Children With Borderline to Moderate Intellectual Disability. I: Prevalence and Impact

Objective: To assess the prevalence, comorbidity, and impact of DSM-IV disorders in 7- to 20-year-olds with intellectual disability. Method: A total of 474 children (response 86.8%) were randomly selected from a sample of students from Dutch schools for the intellectually disabled. Parents completed the anxiety, mood, and disruptive disorder modules of the Diagnostic Interview Schedule for Children. Results: A total of 21.9% of the children met the DSM-IV symptom criteria for anxiety disorder, 4.4% for mood disorder, and 25.1% for disruptive disorder. Similar prevalence rates were found for children who screened positive or negative for pervasive developmental disorder. More than half of the children meeting the criteria for a DSM-IV disorder were severely impaired in everyday functioning, and about 37% had a comorbid disorder. Children with multiple disorders were more likely to be impaired across various areas of everyday functioning. Almost 27% of the diagnosed children received mental health care in the last year. Comorbidity and impairment in everyday functioning increased the likelihood of referral. Conclusions: Most disorders can be observed in intellectually disabled children. Impairment and comorbidity are high. The finding that less than one third of the children with a psychiatric disorder receive mental health care deserves attention.