Undiagnosed autism doesn't directly cause schizophrenia, but autistic individuals have a significantly higher risk (3 to 6 times greater) of developing schizophrenia, linked by shared genetic roots, brain development patterns, and common traits like social withdrawal, with trauma often acting as a trigger for psychosis in autistic people. It's more about shared vulnerabilities and triggers, with both being neurodevelopmental conditions that can sometimes co-occur or be confused due to overlapping symptoms, especially if autism isn't diagnosed early.
Risk of psychosis across ages among ASD people
A recent meta-analysis focused on the few studies (n = 4) that included subjects with autism in their high risk for psychosis cohorts (CHR-P), reporting a pooled prevalence of ASD as high as 11% (range between 2.5 and 40%, Vaquerizo-Serrano et al., 2022).
It was subsequently pointed out that individuals with autism share many of the negative features of schizophrenia, such as social withdrawal and communication deficiencies, but do not share the positive symptoms, mainly involving hallucinations and delusions (Rumsey, Andreasen, & Rapaport, 1986).
Undiagnosed ASD in adults has been linked to higher rates of psychiatric conditions (C. Nylander et al., 2018), social problems (Bishop-Fitzpatrick et al., 2018), increased vulnerability to sexual abuse in women (Bargiela et al., 2016), chronic pain (Bursch et al., 2004), and suicidal behaviors (Richards et al., 2019).
Research suggests that many autistic people also have a mental health problem like depression or anxiety. There are many possible reasons for this, including: Negative attitudes from other people. Non-autistic people may not understand or accept your differences.
Youth with autism have been found to be three to six times more likely to develop schizophrenia than their peers without autism.
Around 90% of autism cases are attributed to genetic factors, meaning autism is highly heritable, with many different genes contributing, rather than a single cause, often interacting with environmental influences during early brain development, though specific environmental factors don't cause it but can increase risk. Twin studies show strong genetic links, with concordance rates between 60-90% in identical twins, and research points to complex interactions of many genes and prenatal/perinatal factors.
Untreated autism can lead to limitations in an individual's ability to become independent in various aspects of life. Difficulties with social interactions and communication can hinder the development of essential life skills, such as forming relationships, managing personal care, and navigating daily tasks.
The "6-second rule" for autism is a communication strategy where a speaker pauses for about six seconds after asking a question or giving information, giving the autistic person extra time to process it without feeling rushed, which helps reduce anxiety and allows for a more thoughtful response, reducing frustration for both parties. Instead of repeating or rephrasing, which can be confusing, you wait, and if needed, repeat the exact same words after the pause.
Bipolar disorder.
People with bipolar disorder often have periods of being “up” or “on” when they're extremely energized or happy, then fall into periods of deep depression. Some people with severe bipolar disorder have delusions or hallucinations. That's why they may be misdiagnosed with schizophrenia.
Autistic traits—such as social communication deficits, cognitive rigidity, and repetitive behaviors—are increasingly recognized in individuals with schizophrenia, particularly in early-onset cases and subtypes with predominant negative symptoms.
Depression, anxiety, and substance abuse are common accompaniments of the schizophrenia condition, and they in turn perturb the clinical picture. For example, depression can cause secondary negative symptoms, panic attacks can drive paranoia, and cannabis abuse can worsen positive and disorganization symptoms.
Risk factors
The co-occurrence of psychopathy in autism is possible but rare (Rogers et al., 2006). However, although the clinical profiles of ASD and psychopathy differ considerably, these two disorders also display numerous shared features. A lack of empathy is common in both disorders.
Symptoms of High Functioning Schizophrenia
Positive symptoms are behaviors or experiences that weren't present before the onset of the condition, often involving psychosis, such as: Hallucinations. Delusions. Disorganized thinking and speech.
Chinning is a form of repetitive self-stimulatory behavior (stimming) that you may notice in children or adults with autism. It involves pressing, rubbing, or holding the chin against objects, surfaces, or even hands to gain sensory input or comfort.
Children with autism may exhibit rigidity, inflexibility and certain types of repetitive behavior such as: Insistence on following a specific routine. Having difficulty accepting changes in the schedule. A strong preoccupation with a particular interest.
"Looping" in autism refers to getting "stuck" in repetitive mental cycles, replaying thoughts, questions, worries, or phrases endlessly, often triggered by stress, sensory overload, or uncertainty, and linked to challenges with executive function and attention. It's a non-clinical term for perseveration or rumination, where an autistic individual's brain struggles to shift focus from an internal loop, which can be mentally exhausting but sometimes also comforting.
Untreated autism can contribute to mental health concerns in individuals. The challenges and frustrations associated with untreated autism, such as social isolation, communication difficulties, and academic struggles, can lead to increased stress, anxiety, and depression.
Top 10 Calming Strategies for Autism
There is not just one cause of ASD. Many different factors have been identified that may make a child more likely to have ASD, including environmental, biologic, and genetic factors.
While the exact reasons are not yet clear, changes in how the disorder is defined, increases in screening, and more awareness certainly contribute to this increase. If you have any concerns about your child's development, speak to a healthcare professional about diagnostic tests.
Donald Triplett, autism's 'Case 1,' dies at 89. Triplett gained media attention for his autism later in life, and he became the face of the effort to research the lives of older adults with autism.
Yes, a majority of autism cases are linked to inherited genetic mutations that run in families. Can You Develop Autism? Autism takes root during fetal development. No evidence suggests you can develop autism later in life.