Adults aged 50 and older who have attention-deficit/hyperactivity disorder (ADHD) may be more likely to develop mild cognitive impairment or dementia, according to a study published in JAMA Psychiatry on October 7, 2026. The research, led by scientists at the University of Pittsburgh School of Medicine, examined health records and genetic information from more than 187,000 adults.
During the study period, 6.7% of participants with an ADHD diagnosis developed mild cognitive impairment or dementia, compared with 3.4% of those without the diagnosis. Researchers found a more than fourfold increase in the statistical hazard of developing these conditions in their initial adjusted analysis. The association became smaller after additional health conditions were taken into account, but it remained significant.
The finding adds to a growing body of research into how ADHD may affect people as they age. It also raises questions about how doctors distinguish lifelong attention and memory difficulties from changes that emerge with cognitive decline.
What the Study Found
Researchers analysed data from the US National Institutes of Health’s All of Us Research Program. The study included 187,341 adults aged 50 and above, with ADHD diagnoses and cases of mild cognitive impairment or dementia identified through medical records. The research team also examined genetic measures associated with ADHD.
Across the full group, 6,462 participants received a diagnosis of mild cognitive impairment or dementia during follow-up. Of these, 203 were among the 3,026 participants with ADHD.
The researchers reported a hazard ratio of 4.60 in their initial adjusted analysis. After accounting for neuropsychiatric conditions, the estimate fell to 3.19. This change matters because it shows that other health factors may explain part of the association, even though they do not appear to account for all of it.
The genetic analysis pointed in a similar direction. Participants in the highest group for genetic susceptibility to ADHD had a 35% higher risk of cognitive impairment than those in the lowest group. Genetic susceptibility estimates a person’s likelihood of developing a condition; it does not determine whether that person will develop it.
Together, the clinical and genetic findings give researchers more reason to investigate a possible connection between ADHD and later-life cognitive health.
Why Might ADHD Be Connected to Dementia?
The study did not establish why the two conditions are associated. One possibility discussed by geriatric medicine and dementia expert Dr. Elizabeth Landsverk, who was not involved in the research, is that difficulties with planning and organisation may make routine healthcare harder to manage for some people with ADHD.
Keeping appointments, following treatment plans and staying on top of conditions such as high blood pressure can require sustained attention. When these tasks become difficult to manage, existing health problems may receive less consistent care. The researchers also noted that participants with ADHD had greater healthcare use overall, including more outpatient visits.
These observations do not prove that healthcare difficulties explain the higher rate of cognitive impairment. ADHD involves several symptoms and experiences, and neurological, behavioural and broader health factors may all be relevant. Further research will be needed to establish which, if any, of these pathways contribute to the association.
Another important complication is that early cognitive decline can sometimes resemble ADHD. Researchers found that the association was less pronounced when there was a longer gap between an ADHD diagnosis and a later diagnosis of cognitive impairment. Meaning, in some cases, early symptoms of cognitive decline may have been mistaken for ADHD or recorded as ADHD before the actual underlying condition was identified.
How Can ADHD Symptoms Be Distinguished from Cognitive Decline?
Attention, organisation, and memory difficulties that you may experience with ADHD can continue into adulthood. Dementia is not a normal part of ageing, and is characterised by a more severe set of cognitive symptoms that affect daily life. Mild cognitive impairment is defined as measurable changes in thinking and memory that are greater than we would expect for someone’s age, but do not always progress to dementia.
The when and the what matters. A person with years of no longer finding things or difficulty organising themselves is different from a person who has only just started to forget familiar tasks, has difficulty managing medication or difficulty with paying bills.
Any marked change from a person’s normal functioning may be reason for concern, mainly if it is affecting daily living. A clinician may assess if new difficulties with judgement, mood, or social behaviour are reasons to visit the doctor. The clinician will take the person’s history, current symptoms, medications, and co-existing conditions before suggesting any further cognitive testing.
What Happens Next?
The findings do not suggest that every person with ADHD will go on to develop dementia and should not be taken to imply that you should expect this decline. The study was observational so it can find an association but not prove that ADHD causes dementia.
The study also could not determine whether ADHD treatment changes the likelihood of developing cognitive impairment. That question remains open and will require research that can account for treatment histories and other factors over time.
For now, the practical message is to take changes in cognitive function seriously, whether or not a person has ADHD. Regular medical care and attention to established risk factors, including blood pressure, diabetes, smoking, alcohol use and physical activity, remain relevant to long-term health. Anyone experiencing persistent or worsening memory problems or difficulty managing everyday tasks should discuss them with a healthcare professional.
The research offers a reason to look more closely at cognitive health in older adults with ADHD. It does not yet provide a clear explanation for the link, or a way to predict which individuals will develop dementia. Those are the questions future studies will need to answer.
