title: Autism Spectrum and psychosis risk in the 22q11.2 deletion syndrome. Findings from a prospective longitudinal study.
abstract: Individuals with 22q11.2 deletion syndrome (22q11DS) have a 25% risk for schizophrenia and related psychotic disorders. Some have hypothesized that Autism Spectrum Disorders (ASDs) diagnosed in children with 22q11DS may actually represent the social-communicative defects often observed during the early developmental stages of schizophrenia.
  
  
  
  We prospectively studied 89 children with 22q11DS to test this hypothesis. At baseline, the Autism Diagnostic Interview was used to assess ASD, evaluating both current and early childhood behaviors. At follow-up, the Schedule for Affective Disorders and Schizophrenia for School-Age Children (K-SADS) was used to determine development of a psychotic disorder or psychotic symptoms.
  
  
  
  The average age (±SD) at first and last assessments was 14.3±1.9 and 19.0±3.0years, respectively. Nineteen (21.3%) children developed a psychotic disorder. Contrary to our hypothesis, there was no significant difference in the proportion that developed a psychotic disorder, comparing those with (n=9, 17.3%) and those without ASD at baseline (n=10, 27%; OR=0.500, 95% CI=0.160-1.569, p=0.235). Similar results were obtained using autistic symptom severity as quantitative predicting variable, psychotic symptoms as the outcome, and when correcting for age, gender and full scale IQ.
  
  
  
  Results indicate that in children with 22q11DS, early childhood autistic features are not associated with an increased risk for subsequent development of psychotic disorders or symptoms, replicating previous retrospective findings in adults with 22q11DS. These results indicate that ASD and psychotic disorders can emerge independently, as pleiotropic phenotypes in the context of 22q11DS.
authors.affiliation: Department of Psychiatry, Rudolf Magnus Institute of Neuroscience, University Medical Center Utrecht, Utrecht, The Netherlands; Dalglish Family Hearts and Minds Clinic for 22q11.2 Deletion Syndrome, Toronto General Hospital, University Health Network, Toronto, Ontario, Canada; Clinical Genetics Research Program, Centre for Addiction and Mental Health, Toronto, Ontario, Canada. Electronic address: a.m.fiksinski@umcutrecht.nl.
authors.forename: A M
authors.initials: AM
authors.lastname: Fiksinski
authors.affiliation: Department of Psychiatry, Rudolf Magnus Institute of Neuroscience, University Medical Center Utrecht, Utrecht, The Netherlands; Dalglish Family Hearts and Minds Clinic for 22q11.2 Deletion Syndrome, Toronto General Hospital, University Health Network, Toronto, Ontario, Canada; Clinical Genetics Research Program, Centre for Addiction and Mental Health, Toronto, Ontario, Canada.
authors.forename: E J
authors.initials: EJ
authors.lastname: Breetvelt
authors.affiliation: Department of Psychiatry, Rudolf Magnus Institute of Neuroscience, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: S N
authors.initials: SN
authors.lastname: Duijff
authors.affiliation: Dalglish Family Hearts and Minds Clinic for 22q11.2 Deletion Syndrome, Toronto General Hospital, University Health Network, Toronto, Ontario, Canada; Clinical Genetics Research Program, Centre for Addiction and Mental Health, Toronto, Ontario, Canada.
authors.forename: A S
authors.initials: AS
authors.lastname: Bassett
authors.affiliation: Department of Psychiatry, Rudolf Magnus Institute of Neuroscience, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: R S
authors.initials: RS
authors.lastname: Kahn
authors.affiliation: Department of Psychiatry, Rudolf Magnus Institute of Neuroscience, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: J A S
authors.initials: JAS
authors.lastname: Vorstman
mesh_terms: D058165:22q11 Deletion Syndrome / Q000150:complications* / Q000453:epidemiology* / Q000523:psychology; D000293:Adolescent; D000067877:Autism Spectrum Disorder / Q000150:complications* / Q000453:epidemiology*; D015897:Comorbidity; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D011446:Prospective Studies; D011569:Psychiatric Status Rating Scales; D011618:Psychotic Disorders / Q000150:complications* / Q000453:epidemiology*; D012044:Regression Analysis; D012306:Risk; D055815:Young Adult
keywords: 22q11DS; Comorbidity; Genetic; High risk; Schizophrenia; Velocardiofacial syndrome