- Higher Parkinson’s-related disorder risk in older adults with autism
- Large national claims-data study and its key findings
- How parkinsonism differs from Parkinson’s disease
- The role of antipsychotic medications in the analysis
- Why intellectual disability and autism together mattered most
- Clinical caution, early monitoring, and study limits
Older adults with autism are showing up with Parkinson’s-related movement disorders at noticeably higher rates than people in the general population, and that finding is turning heads for good reason. A large new analysis of Medicare and Medicaid records points to a real pattern, not just a one-off coincidence, especially among people who also have intellectual disabilities.
The research looked at nearly 57 million Americans age 45 and older between 2017 and 2019, which gives the results some serious weight. Across those records, people on the autism spectrum were diagnosed with parkinsonism more often than adults without autism, and the gap held even after researchers tried to account for other factors that could muddy the picture.
Parkinsonism is not exactly the same thing as Parkinson’s disease, but it can look a lot like it on the surface. It covers a set of movement problems such as tremors, muscle stiffness, balance trouble and slower voluntary movement, all of which can make day-to-day life harder in a hurry.
One big question was whether antipsychotic medications were driving the connection, since those drugs can trigger Parkinson’s-like symptoms as a side effect. To get a cleaner look, researchers removed people taking those medications from the analysis, and the higher risk still showed up in neurodivergent groups.
The numbers were striking. In the general population, parkinsonism showed up in about 1.57% of people, while the rate climbed to 3.83% in adults with autism alone, 4.32% in those with intellectual disability alone, and 4.86% in people living with both conditions.
That last group stood out the most, and not by a little. The overlap of autism and intellectual disability appeared to carry the strongest association, which suggests clinicians may need to pay closer attention when motor changes begin in those patients.
Greg Wallace, the study’s lead author, said the findings matter because they point to increased incidence in middle and older adulthood, not just lifelong movement quirks. That distinction is important, because it suggests these cases are not simply a byproduct of autism-related motor differences that were always there.
Neurologist Dr. Lee Murray said the research helps sharpen earlier suspicions by factoring out medication effects. He noted that antipsychotics can create a Parkinson’s-like picture with resting tremor, stiffness, a shuffling gait, stooped posture and a softened voice, but that is still different from classic Parkinson’s disease.
He also pointed out that autism covers a wide spectrum, so the findings should not be read as a blanket prediction for every autistic person. The point is more specific than that: some older patients may be at higher risk, and the warning signs can be easy to miss when they are blended in with existing communication, coordination or behavior differences.
That is where the clinical stakes get real. Experts say it helps when doctors have a solid baseline for motor skills in adulthood, so new tremors, rigidity or gait changes are easier to spot instead of being shrugged off or misread.
The study did have limits, and the researchers were upfront about them. Insurance claims can contain coding mistakes, and billing data cannot show symptom severity, lifestyle factors, genetics or family history in the kind of detail a full clinical exam would.
There is also the issue of who was captured in the data. Because the analysis focused on public insurance programs, older adults with private coverage may not have been fully represented, which means the picture may be even broader than the numbers suggest.
Still, the central message is hard to ignore. When older autistic adults begin to show movement changes, those symptoms deserve a closer look, not a quick assumption, and caregivers, facilities and physicians may need to stay on alert as the years go on.
