The complicated and controversial history linking autism and schizophrenia does little to answer parents’ concerns about the co-occurrence of these two conditions in their children.
Dr. Eugene Bleuler first used the word “autism” in the early twentieth century to describe symptoms related to schizophrenia. More specifically, symptoms of withdrawal into an inner world—which he had observed in his schizophrenic patients.
This withdrawal, or shutting out of the outside world, is one of the areas where autism and schizophrenia may overlap and cause significant diagnostic difficulty. A child’s social withdrawal, accompanied by sensory issues and behavior that may seem like symptoms of psychosis, could leave parents wondering whether the behavior indicates autism or whether childhood onset schizophrenia is a diagnostic possibility.
The two conditions have symptoms and characteristics that may overlap, but there are also many clear differences. While a professional may be able to discern, and diagnose a child according to their symptoms and history, the two conditions are sometimes comorbid and research indicates that those on the autism spectrum may have an elevated risk of developing schizophrenia.
The following discussion will examine some of the general differences and similarities between the two conditions. For parents who are worried about any behavior or symptoms in their child, a visit to the child’s pediatrician is vital. Autism and schizophrenia are conditions with symptoms manifesting differently in each individual; diagnosis may be complicated and should be left to an experienced professional. An aggressive medical intervention is often recommended for childhood onset schizophrenia, therefore accurate diagnosis is of significant importance.
Firstly, what is autism?
Neurodiversity advocates are encouraging better education and more acceptance and celebration of autism as prevalence of the condition rises. More parents are aware of early symptoms and red flags in young children which often leads to early diagnosis and intervention.
In the US The Diagnostic and Statistical Manual of Mental Disorders (5th ed.; DSM–5; American Psychiatric Association, 2013) is used by medical professionals to diagnose autism spectrum disorders (ASD). The DSM-5 criteria for an autism diagnosis is divided into two core areas:
- Deficits in social communication/interaction
- Restricted/repetitive behaviors and/or sensory interests
Symptoms causing deficits in these two areas should cause significant issues in important areas of the child’s life and should be present from early on (even if manifestation due to circumstances only occurs later).
Sensory issues and social withdrawal are also often associated with schizophrenia. In fact, many autism red flags are listed as early warning signs of schizophrenia. Lack of eye contact for example may indicate autism, but it could also predict schizophrenia where poor eye contact is associated with a lack of social motivation and withdrawal.
Autism sometimes presents in a manner where behavior may be misdiagnosed as psychotic symptoms. For example, repetitive behaviors and meltdowns may be diagnosed as catatonia (a group of symptoms characterized by abnormal movements and withdrawal). Along the same vein, the difficulty an individual with autism experiences due to impairment in reading others’ intentions may be classified as paranoia (Lai & Baron-Cohen, 2015)
The DSM-5 diagnostic criteria does however make it clear that schizophrenia has unique symptoms and characteristics.
What is schizophrenia?
Doctors differentiate between childhood onset schizophrenia, and early onset schizophrenia. The first is extraordinary and rare and means symptoms appear before or at the age of 12 or 13. Early onset schizophrenia on the other hand, starts before a child reaches the age of 18.
There is no quick blood test that can confirm the presence or absence of the condition—as is the case with autism, the clinician depends on the identification of a constellation of symptoms.
The symptoms listed in the DSM-5 are quite specific; parents who want further information should consult the manual to obtain all the relevant details. For a diagnosis, two or more of the symptoms have to be present for at least a month. Successful treatment may shorten this required time period. At least one of these symptoms should be number one, two, or three:
- Hallucinations
- Delusions
- Disorganized speech
- Grossly disorganized or catatonic behavior
- Negative symptoms including flattening
The DSM-5 further specifies factors such as level of functioning in addition to the continuous time period that the disturbance should persist for diagnostic purposes. It also lists other conditions which should be ruled out before a diagnosis is made—the disturbance present should not be better explained by schizoaffective disorder, depressive or bipolar disorder—furthermore, the presence of substance use should also be taken into consideration when diagnosing schizophrenia (American Psychiatric Association, 2013).
Parents with a family history of schizophrenia may wonder if it increases the risk for their child with autism. According to research (Chou et al., 2017) a family history of schizophrenia is associated with a higher risk, which increases significantly if both parents have a history of schizophrenia.
It would seem the two conditions are distinct, with very different core symptoms listed for purposes of classification. And yet clinicians do report difficulty when diagnosing children whose symptoms fall on a spectrum somewhere between autism and schizophrenia.
Perhaps it’s the spectrum nature of both conditions—experts are increasingly referring to schizophrenia as a spectrum disorder—and the heterogeneity of symptoms, which is causing the difficulty in diagnosis. This may be part of the reason doctors recommend that parents keep a detailed account of behaviors, characteristics and symptoms displayed by their child to facilitate diagnosis. Time of onset and duration of disturbances are factors your doctor may consider when diagnosing your child.
Is there a link between autism and schizophrenia?
A review and meta analysis (De Crescenzo et al., 2019) examined the presence of autistic symptoms in schizophrenia spectrum disorders. The two conditions share common cognitive features like weak central coherence and impairment in theory of mind; and conclusions from the study (De Crescenzo et al., 2019) show that individuals with schizophrenia have higher levels of autistic symptoms in comparison to control groups.
Not only do those with schizophrenia have higher levels of autistic symptoms, study (Chien et al., 2021) results showed the incidence of psychiatric comorbidities like schizophrenia among individuals with autism were significantly higher than in a comparison group.
The study (Chien et al., 2021) also suggests the incidence of mental disorders were influenced by autism subtypes and gender. The authors found that females with asperger’s had a significantly higher risk for schizophrenia spectrum disorder than males. The study further concluded that individuals with pervasive developmental disorders (not otherwise specified) had a higher risk for major depressive disorder rather than ASD.
Could my autistic child be diagnosed with schizophrenia too?
For parents dealing with challenging symptoms of autism, research suggesting their child may be at a higher risk of developing schizophrenia could cause unnecessary stress and worry. It is important to note, as mentioned previously, schizophrenia is (very) rarely diagnosed in a child under the age of 12 years.
Even if some of your child’s symptoms fit those listed above, your doctor may rule out comorbid schizophrenia or bipolar disorder if the symptoms or behavior is a manifestation of autism. When children go through puberty their behavior changes and challenging autism symptoms may become elevated due to the hormones involved in puberty.
Sensory processing issues found in almost every child with autism may add further difficulty in diagnosing comorbid mental conditions. Sensory impairment sometimes leads to “bizarre behavior” according to neurotypical standards—the behavior may seem atypical but the purpose is self-regulation or regulation of the sensory environment.
In addition, repetitive behaviors, a core symptom of children with autism, may be difficult to differentiate from catatonia (a behavioral syndrome that may include echolalia, grimacing and repetitive movements) which is a symptom associated with schizophrenia.
Therefore, before parents worry about childhood onset schizophrenia, it is important to remember that your autistic child’s behavior may just be evolving as their autism symptoms change. A transition to adolescence may mean behavior becomes more erratic and autism symptoms more intense, diagnosing such behavior as symptoms of psychosis should be left to medical experts. Even professionals with years of diagnostic experience may find it difficult to separate severe symptoms of autism from those associated with comorbid mental conditions.
Symptoms associated with ASD are often misdiagnosed
A study (Raja & Azzoni, 2010) concluded that adult psychiatric service patients with autism are often misdiagnosed. The authors suggest that adult psychiatrists may not be familiar with the diagnosis of ASD. They conclude by saying the high comorbidity rate between schizophrenia and autism may be related to shared neurobiology, but they don’t exclude the possibility that arbitrary restrictions imposed by the current diagnostic system also play a part.
Diagnostics have obviously improved in the last decade since this study was published but it does emphasize the importance of diagnostic criteria. If an autistic child’s behavior changes suddenly, or if they seem increasingly disconnected from reality, parents should ensure the medical professional they choose to consult with is familiar with both autism and other mental disorders.
While most pediatricians are well versed in areas of mental health, childhood onset schizophrenia in a young patient with autism may require a doctor with diagnostic expertise in developmental disorders and childhood onset schizophrenia.
Evolving behaviors
Parents who are familiar with the symptoms of schizophrenia in adults may wonder if the condition presents differently in children. Some doctors report less delusions in children with early onset schizophrenia but more visual hallucinations. Symptoms differ for every individual, but parents often instinctively feel when behavior is out of the range of that which is “normal” for their autistic child.
Symptoms associated with schizophrenia will often become more pronounced with time. The individual may have increasing difficulty with organizing thoughts; delusions and hallucinations may require hospitalization, and antipsychotic medication may be needed.
Close observation
When doctors are diagnosing a child—especially in cases where a developmental disorder is comorbid with a mental condition like schizophrenia or bipolar disorder—a thorough history and careful analysis of behaviors may improve accuracy.
Parents may feel a precise diagnosis is irrelevant as long as symptoms are treated and their child thrives. But in the case of childhood onset schizophrenia a precise diagnosis is important—or in the words of the authors (Driver et al., 2013) of an article titled Childhood Onset Schizophrenia and Early Onset Schizophrenia spectrum disorders: “Diagnosing a child with schizophrenia has profound effects on the treatment course, including the potential for neglecting another disorder, as psychosis often becomes the primary focus.”
References:
American Psychiatric Association. (2013). Diagnostic and statistical manual of mental disorders (5th ed.). https://doi.org/10.1176/appi.books.9780890425596.
De Crescenzo, F., Postorino, V., Siracusano, M., Riccioni, A., Armando, M., Curatolo, P., & Mazzone, L. (2019). Autistic Symptoms in Schizophrenia Spectrum Disorders: A Systematic Review and Meta-Analysis. Frontiers in psychiatry, 10, 78. https://doi.org/10.3389/fpsyt.2019.00078.
Chien, Y. L., Wu, C. S., & Tsai, H. J. (2021). The Comorbidity of Schizophrenia Spectrum and Mood Disorders in Autism Spectrum Disorder. Autism research : official journal of the International Society for Autism Research, 14(3), 571–581. https://doi.org/10.1002/aur.2451.
Chou, I. J., Kuo, C. F., Huang, Y. S., Grainge, M. J., Valdes, A. M., See, L. C., Yu, K. H., Luo, S. F., Huang, L. S., Tseng, W. Y., Zhang, W., & Doherty, M. (2017). Familial Aggregation and Heritability of Schizophrenia and Co-aggregation of Psychiatric Illnesses in Affected Families. Schizophrenia bulletin, 43(5), 1070–1078. https://doi.org/10.1093/schbul/sbw159.
Driver, D. I., Gogtay, N., & Rapoport, J. L. (2013). Childhood onset schizophrenia and early onset schizophrenia spectrum disorders. Child and adolescent psychiatric clinics of North America, 22(4), 539–555. https://doi.org/10.1016/j.chc.2013.04.001
Lai, M. C., & Baron-Cohen, S. (2015). Identifying the lost generation of adults with autism spectrum conditions. The lancet. Psychiatry, 2(11), 1013–1027. https://doi.org/10.1016/S2215-0366(15)00277-1.
Raja, M., & Azzoni, A. (2010). Autistic spectrum disorders and schizophrenia in the adult psychiatric setting: diagnosis and comorbidity. Psychiatria Danubina, 22(4), 514–521.
