Although autism and schizophrenia are now generally recognized as two
separate illnesses, there is reason to believe that autistic traits and
schizophrenia traits co-occur in some individuals.
For instance, some children with autism disorder have been found to develop
schizophrenia later in life, the negative symptoms of schizophrenia have been
found to co-vary with autistic traits in certain schizophrenia subjects, and a
link between autistic traits and schizophrenia traits was found in a sample of
Now certain individuals with schizotypal personality
disorder—considered the mildest schizophrenia-spectrum
illness—have been found to possess an unusual preponderance of autistic
traits. The results of the study, which was led by Michelle Esterberg, M.P.H.,
of Emory University, were published in the September Schizophrenia
The study included 121 adolescent subjects—35 with schizotypal
personality disorder; 38 with other types of personality disorders
(antisocial, avoidant, borderline, narcissistic, obsessive-compulsive,
paranoid, or schizoid); and 48 with no personality disorders. The subjects
were evaluated for various autistic characteristics, and the results for each
group were then compared.
The schizotypal group scored significantly higher than the other two groups
on a number of autistic traits. They included being socially anxious, having
no close friends, using a limited number of facial expressions, not showing
affection, being unaware of social cues, having circumscribed or unusual
interests, and being resistant to change. Furthermore, the schizotypal group
scored especially high on deficits in the social-functioning domain.
"The present findings indicate significant ... overlap between
autism-spectrum and schizophrenia-spectrum disorders," Esterberg and her
Why might autistic traits and schizophrenia traits coexist in certain
persons? Esterberg and her group suspect that it is because the
autism-spectrum disorders and the schizophrenia-spectrum disorders share some
of the same susceptibility genes or because some of the susceptibility genes
contributing to each spectrum are occasionally inherited together.
For instance, individuals who lack genes on a particular stretch of
chromosome 22—called the 22q11 chromosomal deletion—are known to
be at heightened risk for both the autistic-spectrum and
schizophrenia-spectrum disorders, they pointed out, suggesting that some genes
located in this stretch are complicit in both disorders (Psychiatric
News, September 19).
But one point they are quite sure about, as are many other investigators,
is that autism and schizophrenia are not identical illnesses. One reason is
because 10 of their schizotypal subjects, as well as two other subjects from
the "other personality disorder" category, developed schizophrenia
during a three-year follow-up period. Yet the researchers could find no link
between having autistic traits and subsequently developing schizophrenia.
The study was funded by the National Institute of Mental Health.
An abstract of "Childhood and Current Autistic Features in
Adolescents With Schizotypal Personality Disorder" can be accessed at<www.sciencedirect.com>
by clicking on "Browse A-Z," "S," and then"
Schizophrenia Research." ▪