Autism and Co-occurring Conditions: Schizophrenia

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Schizophrenia and autism are not the same disorder, though they share similarities. Both disorders are characterized by difficulty reading social cues, disorganized thinking, and disorganized or abnormal motor behavior.

There are several differences between the two disorders, however. Autism tends to present early in life, while schizophrenia is usually diagnosed in the teens or early adulthood. Individuals suffering from schizophrenia may also exhibit hallucinations or delusions, which are not considered a symptom of autism.

Several studies have shown a genetic link between autism and schizophrenia. A study from Harvard Medical School that analyzed the DNA of over 60,000 individuals around the world found specific genetic variations within the calcium channel signaling genes, which affect brain communication, that increased the risk for several disorders, including attention deficit hyperactivity disorder, autism, schizophrenia, and bipolar disorder. Another study on mice at the University of Oxford, King’s College London and Imperial College London found that genes linked to autism and schizophrenia were active in a region of the brain known as the subplate, where the first nerve cells develop, early in life.

Another study by Dr. Mark Weiser of Tel Aviv University’s Sackler Faculty of Medicine and the Sheba Medical Center found that individuals with a schizophrenic sibling were 12 times more likely to have autism than individuals who did not have any relatives with the disorder. The authors of the study acknowledge that autism was often misdiagnosed as schizophrenia in previous generations. They say,

“Historically, ASD was often regarded as childhood schizophrenia because the impaired social interactions and bizarre behavior found in ASD were reminiscent of the symptoms of schizophrenia. Indeed, the psychiatrist who coined the term ‘schizophrenia’ counted autism (an active turning away from the external world) as an important distinguishing feature of schizophrenia.”

The two disorders were not considered separate until the 1980s.

Is it possible for someone to suffer from both autism and schizophrenia?

While it is clear that the two disorders share a genetic component, getting a correct diagnosis can be tricky. It’s actually quite rare in young children, since schizophrenia generally does not present until the teens or early adulthood. The defining symptoms of schizophrenia are hallucinations or delusional thinking. It can sometimes be difficult to tell if a patient with autism is exhibiting these symptoms, especially when there are communication difficulties present. People with autism may also appear to exhibit disordered thinking in situations that are stressful for them, and they may have difficulty explaining what they are thinking and feeling to others. Certain medications can cause hallucinations or delusional thinking, so it’s important to rule this out if you fear that your child is suddenly exhibiting these symptoms.

Schizophrenia is generally treated with antipsychotic medications. The decision to medicate is serious and should only be done under the guidance of a qualified physician. Any parent who fears that their child may be suffering from schizophrenia should find a qualified mental health professional, preferably one with experience in both autism and schizophrenia.

To read other articles in this series on autism and co-morbidity click here