A large U.S. study using electronic health records and genomic data found that adults with ADHD were substantially more likely to develop mild cognitive impairment or dementia in later life. The analysis followed more than 187,000 participants aged 50 and older for an average of about 10 years, drawing on data from the All of Us Research Program.
After accounting for age, sex, and health conditions, ADHD was associated with a 4.6-fold higher risk of incident cognitive impairment. The association weakened but remained significant after further adjustments for comorbidities, education, and healthcare use. When restricted to dementia alone, the risk was still about three times higher.
Genetic evidence pointed the same way: participants with the highest polygenic risk scores for ADHD were 35% more likely to develop cognitive impairment than those with the lowest scores. The authors said this concordance between clinical records and genetics suggests the link is not simply an artifact of diagnostic practices.
The findings do not establish causation. The researchers noted potential residual confounding, reverse causation given dementia's long prodromal phase, and selection bias in volunteer cohorts. They also highlighted an open question: whether ADHD treatment could alter dementia risk, citing a recent Israeli study that found no elevated risk among stimulant-treated adults.