Childhood Schizophrenia

1. Childhood Schizophrenia Chapter 21 Robert F. Asarnow

2. Historical Background and Terminological and Conceptual Issues • 1930s: The construct of childhood schizophrenia included children who today would receive DSM-IV diagnoses of autistic disorder, pervasive developmental disorders (PDDs), schizophrenia, or disintegrative psychosis. • 1960s & 1970s: Children with schizophrenia had hallucinations, delusions, and formal thought disorder. • DSM-III, DSM-III R and DSM-IV: Diagnostic criteria for schizophrenia in children was identical to those used for adults, with minor allowances made for how specific symptoms may be manifested in childhood.

3. Diagnostic Issues and DSM-IV Criteria • The DSM-IV states that the essential symptoms of schizophrenia are “delusions, hallucinations, disorganized speech, grossly disorganized or catatonic behavior, and negative symptoms” (American Psychiatric Association, 1994, p. 285). • Taking child development into account, important to differentiate common childhood phenomena such as imaginary friends, magical thinking, and hypnagogic experiences from true delusions and hallucinations.

4. Differential Diagnostic Issues • Making a differential diagnosis involving schizophrenia in children requires ruling out the following psychiatric conditions: • Mood disorders, schizoaffective disorder, PDDs, communication disorders, obsessive compulsive disorder, posttraumatic stress disorder, dissociative disorders, and medical conditions such as seizure disorders, brain tumors, and substance abuse. • Prevalence • Very rare resulted in considerable uncertainty about its prevalence. • Prior to 12 years of age the prevalence rate of such true COS is fewer than 1 in 10,000 (Burd & Kerbeshian, 1987).

5. Developmental Progression and THE Prodromal Phase • Outcome • In general, outcomes in children with schizophrenia are generally worse than when onset is in adulthood (Remschmidt & Theisen, 2005). • Sex Differences • Excess of boys to girls when onset of schizophrenia is prior to 12 years of age. • Nearly equal when onset of schizophrenia is after age 12. • Comorbidity • Most common comorbid diagnoses in children are conduct/oppositional behaviors and atypical depression or dysthymic disorder.

6. Overlap between Autism and COS • Considerable body of biological research pointing to overlap between autism and COS. • “It appears that in autism there is acceleration or excess of early postnatal brain development (1–3 years), whereas in COS there is exaggeration of the brain maturation process of childhood and early adolescence (10–16 years). While autism and COS have been distinguished at the level of clinical symptoms, since DSM III the results of genetic and brain imaging studies indicate that there is overlap in the neurobiological substrates for these disorders” (Rapoport et al., 2009, p.14).

7. Risk Factors • Population-Based Studies • First-degree relatives of patients with adult-onset of schizophrenia is greater • Familial aggregation of schizotypal personality disorder • Concordance rates for schizophrenia are 55.8% among monozygotic twins and 13.5% among dizygotic twins • Specific Genes • Linkage studies: Susceptibility genes have been identified including dysbindin, neuregulin-1, DISC1, G72, and the alpha 7 nictotinic receptor subunit • Cytogenetic Abnormalities • “Rare structural variants” • Endophenotypes • Abnormalities in smooth pursuit eye-movements, neurocognitive functioning, brain structure, brain electrical activity, and autonomic activity

8. Risk Factors • Conclusions Regarding Genetic Findings • High phenotypic variation presents challenges in mapping the pathways from gene to disorder • Little known about the normal function of putative susceptibility genes for schizophrenia or how they may affect processes related to the development of schizophrenia • Drug Abuse • Adolescents with a genetic predisposition for schizophrenia are more likely to develop psychotic symptoms and/or show a greater psychotic response to cannabis, amphetamines, cocaine, and psychomimetic drugs • Obstetric Complications • Development of schizophrenia in adult life was doubled in people with a history of obstetric complications • Parent and Family Characteristics • Dysfunctional family-rearing environments • Maladaptive parent communication patterns

9. Risk Factors • Brain Structure • 9.2% reduction in total brain volume • Progressive loss of brain tissue starting from the back of the brain and spreading forward • Neurocognition • Presence of cognitive impairments is the most robust finding when schizophrenia patients are compared to healthy controls • Neural Networks in Schizophrenia • COS patients show the same general pattern of neuroanatomic and cognitive findings as patients with adult onset of schizophrenia

10. Treatment • Same antipsychotic medications that are used to treat adults with schizophrenia are used to treat children and adolescents with schizophrenia • Because of serious side effects clozapine is usually used only when patients have not responded to other antipsychotic treatments.

11. Theoretical Synthesis and Future Directions • COS may represent a severe, highly genetic, and biologically homogeneous form of schizophrenia in which the biological substrate is more clearly discernible than in adult-onset schizophrenia. • This framework sets the stage for challenging questions: • What causes a small number of children to develop schizophrenia very early in life? • What triggers the onset of psychotic symptoms?