Immaturity and Low IQ May Predict Psychosis: Small Study of Adolescents Suggests That a Broader Neurobiologic Basis for Psychosis Might Exist

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BAL HARBOUR, FLA. -- Adolescents with psychosis demonstrate neurodevelopmental abnormalities that, when combined with age and intelligence testing, correctly discriminate them from adolescents without mental illness, Dr. David Arciniegas reported in a poster presentation at the annual meeting of the American Neuropsychiatric Association.

The findings of his small observational study indicate that a broader neurobiologic basis for psychosis might exist in this population. "It seems most likely that aberrant neurodevelopment manifests clinically in multiple domains of neuropsychiatric function: cognition, behavior, and elemental neurological function," said Dr. Arciniegas of the University of Colorado, Denver.

He compared 12 adolescents with psychotic illnesses with 13 healthy adolescent controls. Six of the adolescents had schizophrenia; six had bipolar disorder with psychotic features. The subjects were aged 10-18 years. In addition to a general clinical evaluation and elemental neurologic examination, all subjects received the Kiddie Schedule for Affective Disorders and Schizophrenia (K-SADS), the Weschler general intelligence test, and the Neurological Evaluation Scale (NES).

The NES is a structured clinical examination of integrative sensory function, motor coordination, motor inhibition, complex motor sequencing, primitive reflexes, eye movements, and short-term memory. Normal children generally exhibit higher NES scores, which decline as they mature. This pattern was noted in the normal controls: NES scores were inversely correlated with age, with younger patients scoring around 15 and older patients scoring below 10.

Among adolescents with psychosis, however, the NES score did not correlate with age. The mean score for all patients was 20, regardless of age. "The kids with psychosis look much more immature than one would expect, and they are not maturing as they get older," Dr. …