The Presentation of Anxiety in Children with Pervasive Developmental Disorders

OBJECTIVE: Although the Diagnostic and Statistical Manual of Mental Disorders, 4th ed. (DSM-IV) diagnostic criteria generally discourage the diagnosis of other Axis I disorders in children with pervasive developmental disorder (PDD), anxiety symptoms are often observed in this clinical population. Moreover, there are some albeit limited data that suggest an association between anxiety and psychotic symptoms in children. Because co-occurring psychiatric symptoms have important clinical implications, this study examined anxiety and psychotic symptoms in children with and without PDD. METHOD: Parents and teachers completed the Early Childhood Inventory-4 (ECI-4) or the Child Symptom Inventory (CSI-4) for children evaluated in a developmental disabilities clinic (PDD) or a child psychiatry outpatient clinic (non-PDD). Children were divided into four groups: 3-5- year-olds with (n = 182) and without (n = 135) PDD, and 6-12-year-olds with (n = 301) and without (n = 191) PDD. The 6-12-year-olds were further divided into high-anxious and low-anxious subgroups based on CSI-4 ratings and compared with regard to severity of psychotic symptoms. RESULTS: Teachers rated preschoolers with PDD as exhibiting more severe anxiety symptoms than the non-PDD group; however, the converse was true for parent ratings. For 6-12- year-olds, both parents and teachers rated children with PDD as significantly more anxious than non-PDD clinic referrals. In general, the severity of anxiety symptoms varied by PDD subtype (Asperger's disorder > PDDNOS > Autistic disorder) and IQ (high > low). Furthermore, highly anxious 6-12-year-olds with PDD received significantly higher parent and teacher ratings of psychotic symptom severity (strange behaviors, hearing voices, illogical thinking, inappropriate affect, and odd thoughts) than our low-anxious group, even when controlling for PDD symptom severity. Moreover, the relation between anxiety level and psychotic symptom severity was similar for both PDD and non-PDD children. Parent and teachers differed in their perceptions of the severity of specific anxiety symptoms. In addition, parent- versus teacher-defined anxiety level groups varied with regard to the differential severity of psychotic symptoms. This finding highlights the importance of continued investigation of source-specific syndromes in children with PDD. Two case vignettes are presented. CONCLUSION: Anxiety appears to be a clinically important concern in many children with PDD. Similarities in anxiety symptom presentation and their association with psychotic symptoms in both children with and without PDD support the possibility of: (1) psychiatric comorbidity in the former; (2) at least some overlap in causal mechanisms for anxiety and psychotic symptoms in both PDD and non-PDD children; and (3) a unique diagnostic entity comprised of PDD, anxiety, and psychotic symptoms. Lastly, clinicians should seriously consider dual diagnoses in children with PDD.