Do personality traits, like being neurotic, boost your chances of getting Alzheimer's disease? Our neurologist contributor breaks down a buzzy recent study.
You may have read about it in the New York Post: “Scientists pinpoint personality traits that increase risk of Alzheimer’s.” A recent study published in Biological Psychiatry found associations between certain personality traits from the list of the “big five” traits — like conscientiousness or neuroticism — and dementia. The results were interesting: The researchers found that people with neuroticism were more likely to develop Alzheimer’s pathology in the brain, while conscientious people were less likely.
Here’s an important clarification, however: While scientists found evidence of some kind of link, what they did not find was a causal effect. So far, there’s no evidence at all that having a particular personality trait can actually increase a person’s risk of developing Alzheimer’s. There could be a lot of other factors at work that cause certain traits and a certain disease to eventually co-exist.
While the study assessed pathology in the brain associated with Alzheimer’s, it did not assess cognitive function or follow up to determine whether these volunteers developed Alzheimer’s or related dementias.
Unfortunately, it is challenging to identify who will and who won’t develop Alzheimer’s or related dementias before the symptoms appear. Many researchers are looking to identify biomarkers of the disease to intervene earlier. That means researchers are rigorously searching through data for early clues, including overlaps between the presence of certain personality traits and the likelihood of developing dementia.
This research was part of the Baltimore Longitudinal Study of Aging, which tracked more than 3,000 participants. Each one completed an extensive “big five” personality quiz and had their brains imaged a year later to look for the build-up of known Alzheimer’s protein biomarkers like beta-amyloid clumps and tau tangles in the brain.
Researchers then looked at associations between protein deposition and the big five personality traits:
- Conscientiousness: Someone who is responsible, careful, and mindful of goals and details
- Agreeableness: Someone who shows respect, compassion and avoids problems.
- Neuroticism: Someone who may be more likely to experience emotions like anxiety and depression.
- Openness: Someone who is curious and open to new experiences.
- Extraversion or extroversion: Someone who seeks excitement and is very sociable.
In this study, neuroticism was associated with more amyloid in the cortex, while conscientiousness was associated with a lower burden.
They also reported similar trends when looking at tau in the entorhinal cortex region of the brain. Afterward, the researchers aggregated data from previous studies finding similar trends in regards to conscientiousness and neuroticism.
These associations were dependent on an individual’s cognitive status, showing more of an effect in cognitively healthy individuals. While the study results are compelling, the results do not look at cognitive function or memory, nor do they measure cognitive decline (It is well known that many people who develop plaques might not ever develop Alzheimer’s).
“There are aspects of neuroticism and conscientiousness that might directly impact the risk of dementia,” the lead author, Antonio Terracciano, professor of geriatrics at Florida State University College of Medicine told Medical News Today.
“Traits like neuroticism shape our emotional life, the way we cope with stress and deal with our feelings,” he added. “Conscientiousness is defined by our level of grit, persistence, and planful attitudes.”
While the study looked at known, potential risk factors in these personality traits, it did not newly link them to dementia. “Because this study is observational, we can’t say for sure what the mechanisms are, and much more research is needed,” Claire Sexton, director of scientific programs and outreach at Alzheimer’s Association, an independent researcher who wasn’t involved in the study, told Medical News Today.
Instead, these personality traits showed small, but significant, associations with beta-amyloid and tau deposition in the brain. Conscientiousness and neuroticism especially, relate to lifestyle choices which themselves are stronger risk factors for Alzheimer’s.
“Highly conscientious individuals have been shown to have healthier lifestyles — in terms of physical activity, smoking, sleep, depression, cognitive stimulation, etc. — than those with lower conscientiousness,” Sexton said. “There is a solid body of research connecting lifestyle, dementia risk, and biomarkers.”
