- About 1 in 40,000 children is diagnosed with schizophrenia, compared to 1 in 100 in adults.
- Schizophrenia ranks among the top 10 causes of disability worldwide.
- Children with schizophrenia may share symptoms with--and have their symptoms mistaken for--autism or other pervasive developmental
disabilities, which affect about 1 in 500 children.
- Child schizophrenia patients are harder to treat and have a worse prognosis than adult schizophrenia patients.
- It is often preceded in children by developmental disturbances, such as lags in motor and speech/language development;
such problems tend to be associated with more pronounced brain abnormalities.
- Symptoms appear prior to age 12.
- Children with schizophrenia often see or hear things that do not really exist, and harbor paranoid and bizarre beliefs.
Causes & Research:
Although it is unclear whether schizophrenia has a single or multiple underlying causes, evidence suggests that it is
a neurodevelopmental disease likely involving a genetic predisposition, a prenatal insult to the developing brain, and stressful
life events. The role of genetics has long been established; the risk of schizophrenia rises from 1% with no family history
of the illness, to 10% if a first degree relative has it, to 50% if an indentical twin has it. Prenatal insults may include
viral infections, such as maternal influenza in the second trimester, starvation, lack of oxygen at birth, and untreated blood
type incompatibility. Studies find that children share with adults many of the same abnormal brain structural, physiological,
and neuropsychological features associated with schizophrenia. The children seem to have more severe cases than adults, with
more pronounced neurological abnormalities. This makes childhood-onset schizophrenia potentially one of the clearest windows
available for research into a still obscure illness process.
For example, unlike most adult-onset patients, children who become psychotic prior to puberty show conspicuous evidence
of progressively abnormal brain development. In the first longitudinal brain imaging study of adolescents, magnetic resonance
imaging (MRI) scans revealed fluid filled cavities in the middle of the brain enlarging abnormally between ages 14 and 18
in teens with early-onset schizophrenia, suggesting a shrinkage in brain tissue volume. These children lost four times as
much gray matter, neuroms and their branch-like extensions, in their frontal lobes as normally occurs in teens. This gray
matter loss engulfs the brain in a progressive wave from back to front over five years, beginning in rear structures involved
in attetion and perception, eventually spreading to frontal areas responsible for organizing, planning, and other "executive"
functions impaired in schizophrenia. Since losses in the rear areas are influenced mostly by environmental factors, the researchers
suggest that some non-genetic trigger contributes to the onset and initial progression of the illness. The finaly loss pattern
is consistent with that seen in adult schizophrenia. Adult-onset patients' brains may have undergone similar changes when
they were teens that went unnoticed because symptoms had not yet emerged, suggest the researchers
In addition to studies of brain structural abnormalities, researchers are also examining a group of measures associated
with genetic risk for schizophrenia. Early-onset cases of illness have recently proven crucial in the discovery of genes linked
to other genetically complex disorders like breast cancer, Alzheimer's, and Crohn's disease. Hence, children with schizophrenia
and their families may play an improtant role in deciphering schizophrenia's molecular roots. Evidence suggests that the rate
of genetically-linked abnormalities is twice as high in children as in adults with the illness. Similarly, schizophrenia spectrum
disorders, thought to be genetically related to schizophrenia, are about twice as prevalent among first-degree relatives of
childhood-onset patients. In one recent study, a third of the families of individuals with childhood onset schizophrenia had
at least one first-degree relative with a diagnosis of schizophrenia, or schizotypal or paranoid personality disorder. This
profile of psychiatric illness is remarkably similar to that seen in parents of adult-onset patients, adding to the likelihood
that both forms share common genetic roots. Other anomalies associated with adult schizophrenia, such as abnormal eye movements,
are also common in families of children with the illness.