Research shows that autism spectrum disorder (ASD) and autoimmune disorders are connected through shared genetic risk factors and immune system activity, though the exact nature of this link is still being studied. Families of children with autism have higher rates of autoimmune conditions like rheumatoid arthritis, type 1 diabetes, and thyroid disease. Some studies also find differences in immune function in people with autism, but these findings do not prove that autoimmune disease causes autism. The relationship is complex and likely involves multiple biological pathways.
What Is the Link Between Autism and Autoimmune Disorders?
The link between autism and autoimmune disorders is one of association, not proven cause and effect. Research consistently shows that people with autism and their close relatives have a higher-than-expected rate of autoimmune conditions. This suggests a shared biological vulnerability rather than one condition directly causing the other.
Autoimmune disorders occur when the immune system mistakenly attacks the body’s own tissues. In autism, some scientists have observed markers of immune activation in the brain and in blood. However, no single autoimmune mechanism has been confirmed to cause or drive autism symptoms. The evidence points to a complicated interplay between genetics, immune regulation, and environmental factors.
What Does the Research Say?
Several large studies have examined the family history of people with autism. A 2015 study in JAMA Psychiatry found that mothers with autoimmune diseases such as psoriasis, rheumatoid arthritis, or type 1 diabetes were modestly more likely to have a child with autism. The risk increase was small, and most children born to mothers with autoimmune conditions do not develop autism.
Other research has looked at immune markers in children with autism. Some studies report higher levels of inflammatory proteins called cytokines in the blood or in spinal fluid. These findings are not universal, and many children with autism have no measurable immune abnormalities. The evidence is consistent enough to suggest that immune dysregulation may play a role in a subset of cases, but not in all.
Genetic studies have identified certain immune-related genes that are more common in people with autism. These genes are involved in regulating immune responses. This overlap adds weight to the idea that the immune system and the nervous system share developmental pathways. Still, genetics alone does not explain the full picture.
How Could Autoimmune Activity Affect Brain Development?
The immune system and the brain communicate constantly, especially during early development. If the immune system is overactive or misdirected, it could potentially interfere with the normal growth of neural circuits. This is a biologically plausible mechanism, but direct evidence in humans is limited.
Some animal studies have shown that activating the mother’s immune system during pregnancy can cause behavioral changes in offspring that resemble autism. These experiments use substances that mimic a viral infection. The results suggest that immune activation at critical times might alter brain development. However, animal models do not perfectly replicate human autism, and the triggers in humans are likely more diverse.
In people with certain autoimmune conditions, antibodies that cross the placenta can affect the fetal brain. This is best documented in conditions like lupus, where maternal antibodies can cause neonatal lupus and affect the developing heart and brain. Whether this happens in a way that leads to autism is not yet clear. Some studies have found particular antibodies in mothers of children with autism that bind to fetal brain proteins, but these findings are preliminary and not widely replicated.
Are Mothers with Autoimmune Conditions at Higher Risk?
Research suggests a small increased risk, but the absolute risk remains very low. Most women with autoimmune diseases have children who do not have autism. The conditions most often studied include rheumatoid arthritis, type 1 diabetes, thyroid disease, and psoriasis.
The risk appears highest when the autoimmune condition is active during pregnancy. For example, a 2019 study in Pediatrics found that women with a history of autoimmune disease had about a 30% higher odds of having a child with autism compared to women without. This increase sounds large but translates to a modest increase in actual numbers. The baseline risk of autism is about 1 in 36 children in the United States. A 30% increase would raise that risk to roughly 1 in 28.
It is important to note that many factors contribute to autism risk, and maternal autoimmune disease is just one of many. Genetics, parental age, and prenatal exposures all play a role. No single factor determines the outcome.
Can Treating Autoimmune Conditions Affect Autism Symptoms?
This is an area of active investigation, but no clinical guidelines currently recommend treating autoimmune activity in people with autism. Some small trials have tested immune-modulating medications such as anti-inflammatory drugs or immunoglobulin therapy. Results have been mixed and generally inconclusive.
A few studies have looked at whether treating a mother’s autoimmune disease during pregnancy reduces autism risk in the child. Early evidence is limited and not strong enough to change standard prenatal care. Current recommendations are for pregnant women with autoimmune conditions to follow their doctor’s advice for managing their disease, using medications that are safe in pregnancy.
No study has confirmed that any immune-based treatment improves core autism symptoms such as social communication difficulties or repetitive behaviors. Some clinicians may prescribe treatments for co-occurring conditions like allergies or gastrointestinal issues, which are more common in autism, but that is separate from targeting autoimmunity.
What Should Parents and Patients Know?
The connection between autism and autoimmune disorders is real but not straightforward. If you or your child has autism and a family history of autoimmune disease, it does not mean one caused the other. Both conditions likely arise from a combination of genetic and environmental influences.
There is no test to predict autism based on immune markers. No vaccine or infection has been proven to cause autism through autoimmune mechanisms. That myth has been thoroughly debunked by decades of research.
If a child with autism also has symptoms of an autoimmune condition—such as unexplained joint pain, fatigue, rashes, or digestive problems—it is worth discussing with a pediatrician. Autoimmune diseases can occur alongside autism, and diagnosing them early can improve quality of life. But routine screening for autoantibodies in all children with autism is not currently recommended.
The most helpful approach is to focus on evidence-based autism interventions—behavioral therapy, speech therapy, occupational therapy, and educational support. While research on the immune connection may eventually lead to new treatments, that day is not here yet. Promising leads exist, but they remain in the research phase.
Frequently Asked Questions
Can autoimmune disease cause autism?
No direct causal link has been proven. Some studies show a higher risk of autism in children of mothers with autoimmune conditions, but most children born to these mothers do not develop autism.
Is there a blood test for autism related to autoimmune markers?
No. There is no FDA-approved blood test for autism. Immune markers are studied in research settings but are not used for diagnosis or prediction.
Should a child with autism be tested for autoimmune disorders?
Only if they have symptoms suggestive of an autoimmune condition, such as joint pain, fatigue, or unexplained rashes. Routine testing is not recommended.
Do anti-inflammatory diets help autism symptoms?
Limited evidence exists. Some families report improvements, but no large controlled trials have confirmed that anti-inflammatory diets change core autism symptoms. Dietary changes should be discussed with a doctor.
