October 11, 2026 — Adults with attention deficit hyperactivity disorder may face a far higher risk of dementia later in life than previously understood, according to the largest study of its kind — and the link shows up in their genes as well as their medical records.
The research, published in JAMA Psychiatry by a team at the University of Pittsburgh, followed more than 187,000 adults aged 50 and older for an average of ten years using the US National Institutes of Health’s All of Us research programme. Among the 3,026 participants with an ADHD diagnosis, 6.7 per cent developed mild cognitive impairment or dementia, compared with 3.4 per cent of those without ADHD.
After adjusting for age, sex, education and other health conditions, people with ADHD faced more than four times the risk of cognitive impairment. Crucially, the association also appeared in participants’ genetic data: those with the highest genetic risk scores for ADHD had a 35 per cent greater chance of cognitive decline, even without a formal diagnosis.
Lead author Dr Tharick Pascoal, associate professor of psychiatry and neurology at Pitt, said the convergence of clinical and genetic evidence gives researchers greater confidence the link is real rather than an artefact of how ADHD gets diagnosed. The association held even when at least eight years separated the ADHD diagnosis from the onset of cognitive trouble.
The study does not prove ADHD causes dementia, and open questions remain — including whether ADHD medications or better cardiovascular care might lower the risk. But the authors say the findings argue for treating ADHD as a lifelong brain-health consideration, not just a childhood condition.
Researchers stress that no one should read the findings as a prediction about any individual — most people with ADHD in the study never developed cognitive impairment. But they say the results make a strong case for clinicians to consider long-term brain health when treating ADHD in midlife, and for scientists to investigate whether existing treatments, or better management of heart health, could change the trajectory.
