ADHD may leave a cognitive mark decades later

Clinical takeaway: Consider cognitive monitoring as patients with ADHD age, particularly those with long-standing symptoms or multiple vascular and psychiatric comorbidities, as ADHD may be associated with an elevated risk of later-life cognitive impairment.

ADHD is increasingly recognized as a lifelong condition, yet its implications for cognitive aging remain unclear. Prior studies from several countries have suggested a connection between ADHD and dementia risk, but concerns remained about diagnostic bias and confounding. This study pooled electronic health record and genetic data to examine whether both clinical ADHD and inherited ADHD risk point in the same direction.

In a cohort of 187,341 adults aged 50 years and older in the NIH All of Us Research Program, 3,026 had an ADHD diagnosis and were followed for a mean of about 10 years. During follow-up, cognitive impairment, defined as mild cognitive impairment (MCI) or dementia, developed in 6.7% of participants with ADHD compared with 3.4% of those without ADHD. After adjustment for demographics, comorbidities, and other factors, ADHD was associated with more than a fourfold higher risk of incident cognitive impairment. Even in analyses designed to reduce confounding, the association remained significant.

The genetic analysis told a similar story. Participants with the highest polygenic risk for ADHD had a 35% greater risk of developing cognitive impairment than those with the lowest genetic risk, supporting the possibility that the finding is not solely explained by differences in diagnosis or healthcare use. The association persisted even when researchers required up to 8 years between ADHD diagnosis and onset of cognitive impairment.

Among participants who developed MCI or dementia, those with comorbid ADHD reported poorer mental health, lower quality of life, and lower social satisfaction. They also had 20% higher overall healthcare utilization and 34% more outpatient visits in the year after cognitive impairment diagnosis.

“Two different kinds of evidence are pointing in the same direction,” said senior author Tharick A. Pascoal, MD, PhD. “This doesn’t prove that ADHD causes dementia, but 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.”

Source: Bauer-Negrini G, et al. (2026 Oct 7) JAMA Psychiatry. Attention-Deficit/Hyperactivity Disorder and Late-Life Cognitive Impairment