Director’s Message: Autism and Aging – An area in need of urgent research

By David G. Amaral, Ph.D., Scientific Director of Autism BrainNet

While autism is typically thought of as a childhood disorder, for many autistic individuals, symptoms persist throughout life. Recently, several papers have reported that autism is associated with an increased likelihood of presenile dementia, senile dementia and Parkinson’s disease. A 2021 study published in Autism Research (Vivanti et al. 2021) based on analysis of Medicaid records in the United States found that autistic individuals were 2.6 times more likely to be diagnosed with presenile dementia (occurring before age 65) than non-autistic individuals. More recently, this conclusion has been expanded (Vivanti et al. 2025) to all forms of dementia based on analysis of both Medicaid and Medicare records.

The findings suggested that autistic individuals were prone to a “markedly elevated prevalence of identified dementia diagnoses.” There are many types of dementia, and it is not clear whether autistic individuals are more prone to one, for example Alzheimer’s disease, than others. Similarly, early studies with small numbers of subjects (Starkstein et al. 2015) suggested that older autistic individuals might also be more prone to Parkinson’s disease. This has recently been confirmed and extended in a very large-scale study carried out in Sweden (Yin et al. 2025). This study was based on Swedish medical records and included 2,278,565 individuals. They found that Parkinson’s disease occurred in 438 of 2,226,611 nonautistic individuals (1.3 cases/100,000) and in 24 of 51,954 autistic individuals (3.9 cases/100,000). It is unknown why having autism increases the chances of being diagnosed with one of these age-related, neurodegenerative diseases. An important first step to getting a clearer understanding will be examining the brains of autistics for the telltale signs of dementia or Parkinson’s disease to determine if they are similar or different from nonautistic individuals.

In the last three decades, we have seen enormous growth in research on the causes and trajectories of autism. There has been tremendous progress in identifying genetic risk factors and understanding much about the early developmental features of autism. But, with a worldwide population of autistics numbering 60-75 million and perhaps 20 million who are older than 40, it becomes increasingly urgent to understand what to expect for aging autistics.

Autism BrainNet makes it possible for researchers worldwide to look for genetic and neuropathological changes associated with autism. There are so many studies yet to do to provide a complete understanding of the causes and life trajectory of the condition. It would be very informative to determine, for example, whether the hallmark features of Alzheimer’s disease, the so-called beta-amyloid plaques and tau tangles, are more common in autistic brains than in non-autistic brains. If so, that might suggest that there are shared causes for both conditions. To the best of our knowledge, this is a question that has not yet been comprehensively studied.

Autism BrainNet accepts postmortem brain donations from autistic individuals of all ages and, regardless of other co-existing health conditions. We encourage older autistic individuals, their family members, and/or guardians to learn about the donation process and to consider whether postmortem brain donation is an option. We believe that the decision to become a brain donor should be made long before death is imminent or as part of long-term planning. Talking with family members and caregivers will help ensure that the wish for brain donation will be honored at the time of death. By doing so, autistic individuals and their families will contribute to research to improve the quality of life for the community of living autistics.

As always, we are happy to answer any questions about brain donation. You can reach us by sending a message to [email protected] or calling our 24/7 helpline number at 877-333-0999.

We thank you for your interest and your partnership.