“Evidence for Early-Childhood, Pan-Developmental Impairment Specific to Schizophreniform Disorder: Results From a Longitudinal Birth Cohort”, 2002-05 (; backlinks):
Background: Childhood developmental abnormalities have been previously described in schizophrenia. It is not known, however, whether childhood developmental impairment is specific to schizophrenia or is merely a marker for a range of psychiatric outcomes.
Method: A 1-year birth cohort (1972–197351ya) of 1,037 children enrolled in the Dunedin Multidisciplinary Health and Development Study was assessed at biennial intervals between ages 3 and 11 years on emotional, behavioral, and interpersonal problems, motor and language development, and intelligence. At age 11 years, children were asked about psychotic symptoms. At age 26 years, DSM-IV diagnoses were made using the Diagnostic Interview Schedule. Study members having schizophreniform disorder (n = 36 [3.7%]) were compared with healthy controls and also with groups diagnosed as having mania (n = 20 [2%]) and non-psychotic anxiety or depression disorders (n = 278 [28.5%]) on childhood variables.
Results: Emotional problems and interpersonal difficulties were noted in children who later fulfilled diagnostic criteria for any of the adult psychiatric outcomes assessed. However, statistically-significant impairments in neuromotor, receptive language, and cognitive development were additionally present only among children later diagnosed as having schizophreniform disorder. Developmental impairments also predicted self-reported psychotic symptoms at age 11 years.
These impairments were independent of the effects of socioeconomic, obstetric, and maternal factors.
Conclusion: The results provide evidence for an early-childhood, persistent, pan-developmental impairment that is specifically associated with schizophreniform disorder and that predicts psychotic symptoms in childhood and adulthood.