Published October 7, 2026 at 11:00 AM EDT

Adults with attention deficit hyperactivity disorder (ADHD) face a higher risk of developing dementia or other cognitive impairment later in life. A new study from the University of Pittsburgh found that people with ADHD were four times more likely to develop cognitive impairment over time.

The research, published in JAMA Psychiatry, does not prove that ADHD causes dementia. But it does build upon previous evidence that suggests a link between the two disorders. The study also found those with a genetic predisposition for ADHD face a greater chance of cognitive decline even if the patient never received an ADHD diagnosis.

“Our findings align with and expand a growing literature supporting an association between ADHD and increased risk of [mild cognitive impairment] and dementia,” researchers said in the paper.

The study analyzed medical records and genetic data from more than 187,000 adults aged 50 and older. The analysis showed that 6.7% of participants with ADHD developed dementia or some form of cognitive impairment compared with 3.4% of those without ADHD. After accounting for factors like age, sex and other health conditions, researchers found that people with ADHD faced four times greater risk of cognitive impairment than those without.

Researchers did not theorize what connects ADHD and cognitive decline later in life. But there may be a genetic factor.

Unlike previous research that relied solely on medical records — which can be slanted by uneven healthcare access and whether a clinician recognizes symptoms of either disorder — Pitt’s study found that the link also appeared in participants’ genetic data.

That convergence strengthens the evidence of an association between ADHD and dementia, according to the study’s lead author Dr. Tharick Pascoal, associate professor of psychiatry and neurology at Pitt.

“Seeing the same pattern show up independently in medical records and in people's genes gives us greater confidence that the association is not simply an artifact of how ADHD gets diagnosed,” Pascoal said. “Two different kinds of evidence are pointing in the same direction.” 

The genetic data reinforcing the link between the two conditions is important, said study author and psychiatrist Dr. Douglas Leffa, because ADHD can be difficult to diagnose, especially in adulthood.

“ADHD is a clinical diagnosis that can be very challenging,” Leffa said. “There’s a lot of other psychiatric disorders that can cause symptoms that look like ADHD.”

Depression, anxiety and bipolar disorder can all present symptoms that resemble the hallmark traits of ADHD such as difficulty focusing, low motivation and memory issues.

While ADHD is not caused by a single gene, inherited differences in an individual’s DNA can increase the likelihood of the disorder. Still, Leffa warned that genetic predisposition does not guarantee a patient will develop ADHD.

“Someone might have a higher genetic liability and never develop the disorder,” Leffa said.

And despite an elevated risk, approximately one in 15 participants with ADHD actually exhibited cognitive decline.

“What that means is that most people with ADHD did not develop cognitive impairment,” Leffa said.

Questions remain about whether ADHD medications like stimulants have an effect on a patient's risk or whether managing cardiovascular health — which is also linked to ADHD and dementia — could help.

Leffa said that should offer some reassurance for people with ADHD.

“People with ADHD should not interpret these findings as meaning that they are going to develop dementia,” Leffa said. “The findings suggest that ADHD may be one factor associated with cognitive health later in life.”

The findings suggest, Leffa added, that medical providers “should be attentive to cognitive changes as people with ADHD age while continuing to investigate why this association exists and whether there are interventions that could ultimately reduce that risk.”

In the meantime, researchers urged practicing healthy brain habits as good advice for those with ADHD who are concerned about cognitive decline as they age. Those habits include good sleep, a healthy diet, regular exercise, managing conditions like high blood pressure and cholesterol and staying mentally active by learning new skills.