An open trial of clozapine in 11 adolescents with childhood-onset schizophrenia

OBJECTIVE: To review the response of 11 adolescents with childhood-onset schizophrenia to a 6-week open clozapine trial. METHOD: Eleven children meeting DSM-III-R criteria for schizophrenia had a 6-week open trial of clozapine (mean sixth week daily dose 370 mg). Behavioral ratings included the Brief Psychiatric Rating Scale and Children\u27s Global Assessment Scale. RESULTS: More than half showed marked improvement in Brief Psychiatric Rating Scale ratings by 6 weeks of clozapine therapy compared to admission drug rating and compared to a systematic 6-week trial of haloperidol. CONCLUSIONS: This open trial indicates that clozapine may be a promising treatment for children and adolescents with schizophrenia who do not respond well to typical neuroleptics. A double-blind placebo-controlled study is ongoing

Quantitative magnetic resonance imaging of the corpus callosum in childhood onset schizophrenia

Corpus callosum size has been found to be abnormal in adult schizophrenia, and other studies have implicated abnormal interhemispheric communication in this disorder. To assess continuity with brain abnormalities in the later onset disorder and to further localize brain maldevelopment, this structure was examined in a unique sample of childhood onset schizophrenics. Anatomic brain magnetic resonance imaging scans were acquired for 25 patients (mean age 13.9 +/- 2.1) who had onset of schizophrenia by age 12 (mean age at onset 9.9 +/- 1.9) and 55 normal children. The midsagittal area of the corpus callosum was divided into seven sections. With no adjustment for brain volume, no diagnostic differences were observed. After adjustment for the smaller cerebral volume of the schizophrenics, larger total, anterior and posterior corpus callosum areas emerged for the schizophrenics. These findings provide further evidence for continuity between childhood onset and later onset schizophrenia and support other studies showing white matter sparing in the context of decreased cortical volume

Pubertal development and onset of psychosis in childhood onset schizophrenia

In this study, pubertal development was examined for a sample of children and adolescents with childhood onset schizophrenia (COS) defined as psychosis by age 12. Developmental and psychiatric histories were obtained for 28 adolescents (mean age 14.5 +/- 2.3 years) with severe, treatment refractory COS (14 males, 14 females). Age of onset of psychosis was also examined in relation to menarche and development of secondary sex characteristics. Girls had a trend towards developing secondary sex characteristics earlier than boys (P = 0.06), consistent with North American norms. Males (N = 14) and females (N = 14) had similar age of onset of psychosis. The age of development of secondary sex characteristics was associated with onset of psychosis for girls, but this finding was driven by one outlier. There was no significant correlation between development of psychosis and menarche. Neither male nor female probands differed significantly from their well siblings or from North American norms in their age of onset of pubertal development. There was no evidence of early onset of secondary sex characteristics for this sample. Finally, there was an absence of a clear relationship between onset of psychosis and indices of sexual development for these very early onset cases

Childhood-onset schizophrenia: the severity of premorbid course

OBJECTIVE: To review the premorbid histories of 23 children meeting DSM-III-R criteria for schizophrenia with onset before age 12 years and to compare these with childhood data of later-onset schizophrenics. METHOD: Premorbid features up to 1 year before onset of first psychotic symptoms were rated from hospital and clinic records, clinical interviews, rating scales, and tests. RESULTS: In keeping with previous studies, specific developmental disabilities and transient early symptoms of autism, particularly motor stereotypies, were common. Comparison with the childhood of later-onset schizophrenics showed greater delay in language development, and more premorbid speech and language disorders, learning disorders, and disruptive behavior disorders. (Sixty percent had received or were estimated to meet criteria for one or more clinical diagnoses.) CONCLUSIONS: Childhood-onset schizophrenia may represent a more malignant form of the disorder, although selection and ascertainment bias cannot be ruled out. The presence of prepsychotic language difficulties focuses attention on the importance of early temporal and frontal lobe development; early transient motor stereotypies suggest developmental basal ganglia abnormalities and extend previous findings seen in the childhood of later-onset patients

Childhood-onset schizophrenia: brain MRI rescan after 2 years of clozapine maintenance treatment

OBJECTIVE: The effect of clozapine on striatal morphology was examined in adolescents with childhood-onset schizophrenia. METHOD: Eight adolescent patients with onset of psychosis before age 12 and eight matched comparison subjects had initial and 2-year follow-up brain magnetic resonance imaging scans. Basal ganglia and lateral ventricle volumes were measured. The patients were on a clozapine regimen during the 2-year interim. RESULTS: Caudate volume was larger in the patients at the initial scanning, decreased in the patients between scans, and did not differ significantly between the patients and the comparison subjects at the second scanning. CONCLUSIONS: Caudate enlargement in patients with childhood-onset schizophrenia who are taking typical neuroleptics appears to be secondary to medication exposure. Rescanning to examine basal ganglia morphology is indicated for these patients when they are taking an atypical neuroleptic

Cerebrospinal fluid monoamine metabolites in childhood-onset schizophrenia

OBJECTIVE: Pediatric studies of cerebrospinal fluid (CSF) monoamine metabolites in childhood-onset schizophrenia may help to elucidate both pathophysiology and treatment response in early-onset psychosis. METHOD: CSF homovanillic acid (HVA), 5-hydroxyindoleacetic acid (5-HIAA), and 3-methoxy-4-hydroxyphenylglycol (MHPG) and serum prolactin were measured during drug-free and antipsychotic medication conditions in 18 patients (mean age = 14.2 years, SD = 1.7) who had onset of schizophrenia by age 12 (mean age at onset = 9.9 years, SD = 1.8). Relationships between changes in CSF monoamines and serum prolactin and clinical outcome were examined, and the degree of change in CSF monoamines in response to clozapine treatment was compared with that for 16 patients with later-onset schizophrenia. RESULTS: Despite patients\u27 significant clinical improvement with treatment, CSF monoamine concentrations and ratios of HVA/5-HIAA and HVA/MHPG did not significantly change with 6 weeks of either haloperidol or clozapine treatment. Serum prolactin levels increased during haloperidol treatment. Clozapine had similar effects on CSF monoamines in patients with childhood- and later-onset schizophrenia. CONCLUSIONS: While these data are compatible with continuity between childhood- and later-onset schizophrenia, they also highlight the complexity of the biochemical events mediating clinical changes in schizophrenia

Genetic variation at the 22q11 PRODH2/DGCR6 locus presents an unusual pattern and increases susceptibility to schizophrenia

The location of a schizophrenia susceptibility locus at chromosome 22q11 has been suggested by genome-wide linkage studies. Additional support was provided by the observation of a higher-than-expected frequency of 22q11 microdeletions in patients with schizophrenia and the demonstration that ≈20–30% of individuals with 22q11 microdeletions develop schizophrenia or schizoaffective disorder in adolescence and adulthood. Analysis of the extent of these microdeletions by using polymorphic markers afforded further refinement of this locus to a region of ≈1.5 Mb. Recently, a high rate of 22q11 microdeletions was also reported for a cohort of 47 patients with Childhood Onset Schizophrenia, a rare and severe form of schizophrenia with onset by age 13. It is therefore likely that this 1.5-Mb region contains one or more genes that predispose to schizophrenia. In three independent samples, we provide evidence for a contribution of the PRODH2/DGCR6 locus in 22q11-associated schizophrenia. We also uncover an unusual pattern of PRODH2 gene variation that mimics the sequence of a linked pseudogene. Several of the pseudogene-like variants we identified result in missense changes at conserved residues and may prevent synthesis of a fully functional enzyme. Our results have implications for understanding the genetic basis of the 22q11-associated psychiatric phenotypes and provide further insights into the genomic instability of this region

Cerebral glucose metabolism in childhood onset schizophrenia

Decreased frontal cortical glucose metabolism has been demonstrated in adult schizophrenics both at rest and while engaging in tasks that normally increase frontal metabolism, such as the Continuous Performance Test (CPT). The authors tested the hypothesis that adolescents with childhood onset schizophrenia would also demonstrate hypofrontality while performing the CPT. Cerebral glucose metabolism was examined in 16 adolescents (mean age 14.1 +/- 1.7) with onset of schizophrenia by age 12 (mean age at onset 9.9 +/- 1.8) and 26 healthy adolescents selected to be similar in age, sex and handedness using positron emission tomography and 18F-fluorodeoxyglucose. Patients with childhood onset schizophrenia made fewer correct and more incorrect identifications on the CPT. Region of interest analysis revealed no significant group differences in global cerebral glucose metabolism, but increased metabolic rate in supramarginal gyrus (F = 6.74, P \u3c 0.05) and inferior frontal gyrus/insula (F = 7.09, P \u3c 0.05) and decreased metabolic rate in middle frontal gyrus (F = 6.72, P \u3c 0.05) and superior frontal gyrus (t = 2.04, P \u3c 0.05) in schizophrenics. Comparison of effect sizes with an identically designed study of adult schizophrenics did not indicate more severe hypofrontality in childhood onset schizophrenia. Pixel-based analyses indicated a more complex pattern of group differences in cerebral metabolism with bilaterally increased cerebellar metabolic rate in childhood onset schizophrenics. These findings suggest that childhood onset schizophrenia may be associated with a similar, but not more severe, degree of hypofrontality relative to that seen in adult onset schizophrenia