Study Reveals Adult ADHD Nearly Triples the Risk of Dementia

Earlier this week, an article published in JAMA Network Open evaluated the connection between attention deficit hyperactivity disorder (ADHD) and dementia. Investigators in the publication calculated that adult ADHD was linked to a 2.77 times greater risk of dementia when adjusting for other factors.

According to the publication, there are modifiable dementia risk factors that are also consequences of ADHD: depression, midlife hypertension, smoking, type 2 diabetes, low education levels, and low physical activity levels. That data, combined with the understanding that some adult ADHD symptoms mimic dementia symptoms, prompted this research.

The study looked at patients ages 51–70 without ADHD or dementia diagnoses who entered the cohort in January 2003 and had a follow-up in February 2020.

At the time of follow-up, approximately 0.7% of participants had received an adult ADHD diagnosis. Over ten-fold, 7.1%, had been diagnosed with dementia. Among the patients with an adult ADHD diagnosis, the rate of dementia was roughly 13.2% compared to 7.0% among patients without adult ADHD.

Using Cox regression models to quantify associations and calculate hazard ratios, the researchers initially concluded that dementia risk was 3.62 times greater in patients with adult ADHD. However, after adjusting for covariates, including sex, socioeconomic status, depression, obesity, hypertension, heart disease, traumatic brain injuries, Parkinson’s disease, migraine, and mild cognitive impairment, they concluded that adult ADHD was linked to a 2.77 times higher risk of dementia.

“In this cohort study of 109 218 participants followed up to 17.2 years, after adjustment for 18 potential sources of confounding, the primary analysis indicated that an adult ADHD diagnosis was associated with a 2.77-fold increased dementia risk. Complementary analyses generally did not attenuate the conclusion of the primary analysis. This finding suggests that policymakers, caregivers, patients, and clinicians may wish to monitor ADHD in old age reliably,” concluded researchers in the publication.

Future research is necessary to confirm the link between the two conditions. Additionally, researchers may consider the implications of this link on clinical research and drug development.