New Study Reveals The Personality Traits Associated With Dementia Risk

Research suggests certain characteristics may be linked with the disease. Here's why, and what you can do about it.
New research found a link between a negative affect and dementia risk.
amriphoto via Getty Images
New research found a link between a negative affect and dementia risk.

Could your personality affect your memory?

A recent meta-analysis published in Alzheimer’s and Dementia, the journal of the Alzheimer’s Association, found a connection between certain personality traits and the risk of dementia. The data was made up of eight smaller studies, totalling 44,531 people age 49 to 81. Of the group, 1,703 people developed dementia. Participants took part in personality assessments and underwent brain examinations after they died.

Researchers compared dementia diagnoses with the “big five” personality traits, which are agreeableness, openness, extroversion, conscientiousness and neuroticism. They also compared diagnoses in people who had either a positive affect (a personality that leans more toward positive traits like joy, enthusiasm and confidence) and negative affect (someone who tends to have more emotions like anger, nervousness and fear).

People who had high levels of neuroticism and those with negative affect “had a higher risk of developing dementia over the long term,” said Dr. Joel Salinas, a clinical assistant professor of neurology at NYU Langone Health and the chief medical officer of Isaac Health, who was not affiliated with the study.

“And then those who had low levels of conscientiousness, extroversion and that positive affect ... [were] tied to an increase of risk as well,” Salinas added.

Conversely, researchers found that people with a positive affect or personality traits including extroversion and conscientiousness had a lower risk of developing the disease. Those who are extroverted have a more robust social life and get energy from being around others; someone who is conscientious is considered responsible, organised and goal-oriented.

It’s worth noting that while researchers found an association between personality traits and risk of diagnoses of dementia, a clear link was not found between personality and evidence of underlying disease, Salinas said. So while the study suggests that the two may be correlated, researchers still don’t know if personality type is a direct cause of dementia.

“It doesn’t [mean] that these links don’t exist, it just means that either the study was unable to find it ― because the amount of information available was limited for this part of the study ― or that some other factor explains the reason why more people had risk of dementia,” Salinas said.

According to Dr. Riddhi Patira, the leader of the frontotemporal dementia consortium at the University of Pittsburgh Alzheimer’s Disease Research Center who was not affiliated with the study, the study measured clinical diagnoses of dementia, but it the kind of dementia is unclear — whether it’s Alzheimer’s or general memory problems, for example.

Another limitation, Salinas said, is that the second part of the study, which measured participants’ brain changes, relied on data from fewer participants than the first part of the study.

People with personalities that are linked to higher dementia diagnoses may have certain risk factors.

Patira said that there could be some mediators associated with neuroticism or a negative affect that put people at risk for dementia. For example, people who are neurotic or anxious often have more trouble sleeping than those who aren’t neurotic or anxious.

“And sleep is important for some drainage in the brain ... that’s important for lower inflammation and risk of Alzheimer’s,” Patira explained. “So, there might be something to that that future studies might indicate.”

Additionally, when compared to happy people or those who are positive or extroverted, folks with a more negative affect are more likely to be isolated and have higher rates of depression, Patira said. Depression could impact lifestyle habits like diet and exercise, which are important for a lower dementia risk.

What’s more, Salinas said, people with a more negative affect or anxiety also may not have performed as well on the cognitive tests that doctors use to diagnose dementia. This could have led to more diagnoses based on those results. (Think about it: When you’re feeling anxious or negative before any kind of test or evaluation, you likely won’t perform as well as you would if you were calm and happy.)

While a negative disposition was linked to higher diagnoses of dementia, the study did not find the brain-related changes associated with dementia in these patients.
Catherine McQueen via Getty Images
While a negative disposition was linked to higher diagnoses of dementia, the study did not find the brain-related changes associated with dementia in these patients.

If you do have a more neurotic personality or negative affect, don’t panic.

As mentioned above, this study did not find direct causation between personality and evidence of underlying disease, so don’t panic if you do have a negative affect or are neurotic.

Instead, you can take this study as a learning opportunity. Patira suggests that you take extra care of yourself by exercising, getting good sleep and eating nutritious foods.

That said, she also noted that this requires effort and discipline, and it’s not easy for everyone (you can’t just will yourself to sleep better). If you find that you are still struggling, reach out to a doctor or therapist for additional support.

Overall, certain lifestyle modifications can help decrease your dementia risk, too.

According to Salinas, “there’s quite a lot out there in terms of things that you can do to help to reduce your risk.” Healthy lifestyle habits “just put the odds in your favour that you won’t develop these conditions, or if you do develop it, you’ll develop it later than you would have otherwise.”

To decrease your risk, Salinas said you should:

  • Exercise regularly. “I just really cannot understate [that] people who engage in regular physical activity just have a lower risk of all sorts of conditions, and this is one of them. So out of all the things that you can do, this is the one to really spend time and effort as much as you can,” Salinas said.
  • Eat a healthy diet. A Mediterranean diet has been shown to help with dementia risk.
  • Get enough sleep. “If you have any issues with any sleep disorders, like obstructive sleep apnea ... get treated,” Salinas stressed.
  • Take care of your heart and blood vessels. It’s important to manage conditions like high blood pressure, high cholesterol and diabetes.
  • Have a social support system. “It does seem that having high-quality social connections where you’re able to get support when you need it seems to be protective in some way,” Salinas said.
  • Engage in mentally stimulating activities. “It’s in the act of learning something new that we are more likely to create new brain-cell connections,” Salinas said.
  • Wear a helmet during activities like biking. Head injuries carry an increased dementia risk.

Salinas said that it’s a common misconception that genetics is the sole influencer of dementia risk. In fact, “the vast, vast majority of dementia is not driven by genetics purely,” he said.

By reducing these risk factors and engaging in brain-healthy behaviours as early in your life as possible (and know that it is never too late to start), you can help keep protective factors in place, he said.

It’s not guaranteed that you won’t develop dementia if you follow the advice above, but you’ll likely be in a better position if you do end up developing disease-related changes, Salinas added. It’s worth a shot.