Recent research explores possible connections between adult ADHD and an increased risk of developing dementia, i.e. increased dementia risk.
For decades, whenever anyone mentioned ADHD, the first thing people thought was something along the lines of “that’s the thing boys who can’t sit still get diagnosed with.” While not entirely accurate, that sentence is also not entirely inaccurate. Consider these statistics, published recently by the Centers for Disease Control (CDC) in the report “Prevalence and Trends in Diagnosed ADHD Among US Children and Adolescents, 2017-2022”:
ADHD Among Youth, 2010-2011
- Total: 11.0%
- Boys: 15.1%
- Girls: 6.7%
ADHD Among Youth 2021-2022:
- Total: 10.5%
- Boys: 13.4%
- Girls: 7.4%
The accurate part of how most people think about ADHD is that it’s most common among boys under age 17, i.e. youth and adolescent males. As the statistics demonstrate, ADHD is nearly twice as common in boys than girls. The inaccurate part(s) of how most people think about ADHD is that it only happens to girls, which is not true, and that it can only be diagnosed in youth and adolescents, which is also not true: both females and adults can develop and receive a diagnosis for ADHD.
To learn more about the prevalence of ADHD in youth and treatment of ADHD in adults, please read these articles on our blog:
How Many Children and Teens in the U.S. Have ADHD?
Can a Psychiatrist Help With Adult ADHD?
Given the widespread prevalence across age and demographic groups means understanding everything we can about ADHD is essential. A new study addresses something most people don’t think about when discussing ADHD: an increase in dementia risk. Here’s the question at the core of this recent research effort:
Is adult attention-deficit/hyperactivity disorder (ADHD) associated with an increased risk of dementia?
Let’s take a look at the study.
Adult ADHD and Dementia: About the Study
The authors of the peer-reviewed journal article “Adult Attention-Deficit/Hyperactivity Disorder and the Risk of Dementia” collected data on 109,218 adults born between 1933 and 1952 without a clinical ADHD diagnosis. All participants were between 51 and 70 years old at the start of the study in 2003. The research team followed participants until 2020, and performed statistical analyses on the data between 2022 and 2023.
They assessed the following metrics at baseline and at 5, 10, and 15-year follow up:
- Diagnosis of ADHD
- Diagnosis of dementia
- Receipt/impact of psychostimulant medication
Let’s take a look at what they found.
Adult ADHD and Dementia Risk: The Results
To clarify, the researchers followed a group of adults without ADHD for 15 years and recorded any diagnosis of ADHD, any diagnosis of dementia, and analyzed the results to determine any association between adult ADHD onset and subsequent dementia risk.
Here’s what they found.
A 15-year follow-up, ADHD and dementia:
- Received ADHD diagnosis: 0.7% (730 participants)
- Received dementia diagnosis: 7.1% (7726 participants)
At 15-year follow-up, presence of dementia with and without ADHD:
- Among adults with ADHD: 13.2% (96 /730)
- Rate: 5.9 per 100,000
- Hazard ratio (HR): 2.77
- Among adults without adult ADHD: 7.0% (7630 /108,488)
- Rate: 1.44 per 100,000
- Age at dementia diagnosis, with ADHD:
- 60: 1.6%
- 85: 42%
- Age at dementia diagnosis, without ADHD:
- 60: 0.5%
- 85: 15.2%
Patients diagnosed with adult ADHD showed 277% increased risk of dementia, compared to people without adult ADHD.
Next, let’s look at the impact of psychostimulant medication on dementia among adults diagnosed with ADHD.
Impact of Psychostimulant Medication:
- Received psychostimulant medication: 22.3% (163/730)
- HR for dementia: 1.51, not significant
- Did not receive psychostimulant medication: 76.7%
- HR for dementia: 3.1, significant
Patients with ADHD who received psychostimulant medication showed a 51% increased risk of dementia compared to patients who did not receive psychostimulant medication. Patients with ADHD who did not receive psychostimulant medication showed a 310% increased risk of dementia. In addition, results showed weak evidence of reverse causality, or the onset of dementia increasing symptoms of/diagnosis for ADHD.
Analysis of Risk:
We mention this above, and it’s worth repeating. Compared with the absence of adult ADHD, the presence of adult ADHD was significantly associated with an increased dementia risk:
- HR: 2.77, or a 277% increased risk
Results showed no significant increase in dementia risk among patients with ADHD who received psychostimulant medication.
This is an important part of the results to understand, because untreated ADHD is associated with several physical and mental health outcomes that increase risk of dementia, independent of increased risk associated with the presence of ADHD:
- Depression
- Midlife hypertension
- Smoking
- Type 2 diabetes
All four of those outcomes, in older adults, increase risk of premature mortality, or early death. This demonstrates the value of screening for ADHD in all adult populations, across all demographic groups.
How This Information Helps
Screening can occur at the general practice level, with a family doctor/primary care physician, or with a specialist in mental health with experiencing identifying, diagnosing and treating adult ADHD. This study shows us that wherever it occurs, it should occur.
Here’s how the study authors summarize these results:
“The present study results showed that an adult ADHD diagnosis was associated with a 2.77-fold increased risk of incident dementia. Complementary analyses generally supported this association.”
Early detection of ADHD can allow patients to develop skills to manage their symptoms during adulthood. In addition, with this new knowledge, patients with ADHD can assess their lifestyle to reduce risk of dementia in later adulthood. Lifestyle factors that decrease dementia risk include:
- Managing blood pressure
- Maintaining healthy weight
- Regular exercise
- Healthy diet, high in fruits, vegetables, and whole grains, low in red meat, sugar, and processed foods
- Minimal alcohol consumption
The good news is those protective factors apply to almost all mental health disorders. Therefore, when you take steps to reduce dementia risk, you also decrease risk additional mental health disorders, and increase likelihood of overall wellness – that’s a win-win.
How to Find Treatment and Support for Adults With ADHD: Online Resources
- The American Psychological Association (APA) Therapist Finder is an excellent resource for locating licensed and qualified psychiatrists, therapists, and counselors in your area. Their treatment finder is convenient and easy to use.
- The National Institute of Mental Health (NIMH) maintains a helpful page on attention-deficit disorder (ADHD)
- The National Alliance on Mental Illness maintains excellent resource on attention-deficit disorder (ADHD)
