More than 80% of children with PDD-NOS have co-morbid psychiatric disorders

Background:   Impaired social interaction and communication, as core symtpoms of ASD are often resistant to treatment and are considered to be chronic. Interventions regularly focus on associated symptoms such as hyperactivity, anxiety or aggression. Associated medical and psychiatric symptoms have often been studied in autism but have not been studied in PDD-NOS, the milder, but much more prevalent (PDD-NOS occurs at least twice as often as autism) form of ASD's.

Objectives:  The aim of this study was to assess co-morbid psychiatric disorders and symptoms in school-aged children with PDD-NOS.

Methods: In this study 94 children with PDD-NOS were studied. The Diagnostic Interview Schedule for Children-Parent version (DISC-IV-P) was administered to assess co-morbid disorders and a classification of PDD-NOS was based on standardized, reliable research criteria.

Results: More than 80% of children with PDD-NOS met criteria for at least one co-morbid disorder. Most of them were assigned even more additional disorders. Co-morbid disruptive behavior disorders such as ADHD, and particularly ODD, were present in more than 60% of the cases and more than 50% of the children met criteria for one or more anxiety disorders.

Conclusions: Co-morbid psychiatric disorders occurred in more than 80% of the children with PDD-NOS. In some cases these additional symptoms respond to treatment which subsequently will lead to a better quality of life. Therefore, clinical assessment of children with PDD-NOS should always include assessment of co-morbid psychiatric disorders.