Children's Psychosis Symptoms Should Set Off Alarms

Children with symptoms of psychosis as early as age 12 are likely to have a constellation of other risk factors common to individuals who later develop schizophrenia.

That was the finding of a birth cohort study of 2,232 12-year-olds in Great Britain followed since age 5. The report appeared in the April Archives of General Psychiatry.

The study found that children's psychotic symptoms are familial and heritable and occur in the context of a range of other social, familial, and behavioral risk factors associated with later development of schizophrenia. These include living in a city and disadvantaged social conditions, lower birth weight, greater perinatal complications, social isolation, self-harm, negative maternal expressed emotion, and a chaotic household environment.

The study appears to confirm that children's self-report of psychotic symptoms—including delusions and hallucinations—is reliable, and that those symptoms may be part of a disease process consistent with the neurodevelopmental theory of schizophrenia.

“I think there is a natural inclination to dismiss such symptoms as part of a child's natural flight of fancy,” said study author Avshalom Caspi, Ph.D. “We don't want to be unduly alarmist, but I think one of the things we have learned from this work is that there is a minority of children for whom these kinds of experiences and beliefs signal what is perhaps the early part of a disease process consistent with schizophrenia.”

Participants in the study were members of the Environmental Risk Longitudinal Twin Study, which tracks the development of a nationally representative birth cohort of 2,232 British children. The sample was drawn from a larger birth registry of twins born in England and Wales in 1994 and 1995.

At age 12, children were assessed for psychosis symptoms. When a child endorsed any symptoms, the interviewer prompted the child to describe his or her experience further to discriminate between experiences that were plausibly real (such as, “I was followed by a man after school”) and those that were probably psychotic (“I was followed by an angel who guards my spirit”). Interviewers then coded the descriptions as “not a symptom,” “probably symptom” and “definite symptom,” and the codes were then reviewed and confirmed by a psychiatrist with expertise in schizophrenia, a child and adolescent psychiatrist, and a psychologist with expertise in interviewing children.

Psychosis symptoms were reported by 416 children—291 had “probable” symptoms and 125 had at least one “definite symptom.” Those children were significantly more likely than children not reporting symptoms to have a mother with a psychosis spectrum disorder, to have a family member ever admitted to a psychiatric unit, and to have a family member who had attempted suicide, according to the report.

The following social and behavioral risk factors, common to individuals who later develop schizophrenia, were also found to be statistically significantly more common among the children who had psychosis symptoms at age 12: urban living and socioeconomic disadvantage; low birth weight and low IQ; high maternal expressed emotion score; household chaos and physical maltreatment; antisocial behavior, symptoms of ADHD, social isolation, and internalizing problems at age 5; and antisocial behavior, depressive and anxiety symptoms, tobacco use, and self-harm at age 12.

Caspi told Psychiatric News that the findings build on a November 2000 study reported in the Archives of General Psychiatry in which he and colleagues found that self-reported psychosis symptoms at age 11 predicted a very high risk of schizophreniform disorder at age 26.

For clinicians, that report, combined with the new findings, strongly indicate that psychosis symptoms in childhood are likely to be a marker for an impaired developmental process and should be actively assessed. They generally occur in the context of other psychiatric problems that should be a focus of attention, he said.

For researchers, Caspi said that they may want to recruit children reporting psychotic symptoms into neuroimaging and other studies examining the pathophysiology of schizophrenia.

Nitin Gogtay, M.D., a staff psychiatrist with the Child Psychiatry Branch at the National Institute of Mental Health, reviewed the study and said that the presence of psychosis symptoms in children even younger than 12 is well known.

“However, this study is one of the first to systematically document [the presence of childhood psychotic symptoms] in a large sample and also the first to establish the heritability of such symptoms,” he told Psychiatric News. “The study also strongly validates the need to study psychosis as a ‘dimensional’ phenomenon rather than only as part of a disease or syndrome.”

“Etiologic and Clinical Features of Childhood Psychotic Symptoms: Results From a Birth Cohort Study” is posted at <http://archpsyc.ama-assn.org/cgi/content/full/67/4/328>. “Children's Self-Reported Psychotic Symptoms and Adult Schizophreniform Disorder: A 15-Year Longitudinal Study” is posted at <http://archpsyc.ama-assn.org/cgi/content/full/57/11/1053>.