The present study aimed to investigate psychiatric comorbidity rates and patterns in a sample of clinically referred school-aged children with High Functioning Autism (HFA).

All cases were taken from children and adolescents who consecutively referred to Istanbul Faculty of Medicine, Department Child and Adolescent Psychiatry, Autism Unit. Participants were 30 children and adolescents (29 male, 1 female), aged 6-15 (10y 2m ± 2y 2m) year-old, who met DSM-IV criteria for Autistic Disorder and had a Performance IQ over 70 on WISC-R. Psychiatric comorbidity was assessed using the Schedule for Affective Disorders and Schizophrenia for School Age Children-Present and Lifetime Version (K-SADS-PL).

90% (n=27) of the children had at least one comorbid psychiatric disorder, and 76.6% (n=23) had two or more. In 76.6% (n=23) of the cases at least one Anxiety Disorder was present, and in 63% (n=19) of the children criteria for at least one Disruptive Behavior Disorder was met. The most frequent Axis I psychiatric diagnoses were ADHD (60%), SP (53.3%), Oppositional Defiant Disorder (30%) and OCD (20%).

A very high rate of psychiatric disorders was detected in a small group of clinically referred children and adolescents with HFA. These results underscore the importance of detailed assessment of behavioral and emotional problems in ASDs.