ABSTRACT
Background
Data on psychiatric comorbidities in children with intellectual disability (ID) across subgroups remain limited. Thus, we aimed to investigate comorbidity prevalence by age, sex, ID severity, and socioeconomic status.
Methods
This multicentre, cross-sectional study included 1742 children with ID consecutively recruited from child psychiatry outpatient clinics. Participants were assessed using comprehensive psychiatric interviews, the Strengths and Difficulties Questionnaire, and Clinical Global Impression.
Results
Comorbid psychiatric disorders were present in 86.2% of the sample; 24.7% had one, and 61.5% had two or more. The most common diagnoses were ADHD (44.3%), anxiety disorders (40.0%), oppositional defiant disorder (36.7%), and conduct disorder (29.2%). Comorbidity rates were significantly higher in males, adolescents, those with severe ID, and those from higher-income families. Internalising disorders were more common in females; externalising disorders in males and adolescents.
Conclusions
Our findings suggest the integration of systematic, developmentally sensitive psychiatric screening into standard clinical care for children with ID.