For decades, scientists have searched for early indicators of memory impairment to better detect and slow the progression of cognitive decline.
Some researchers and clinicians have pointed to significant personality changes—like increased neuroticism—as potential early warning signs of Alzheimer’s disease and other forms of dementia.
However, a recent study led by Katsuya Oi, a sociologist at Northern Arizona University, challenges this view, arguing that personality changes often stem from stress and other life events rather than memory impairment.
Published in Scientific Reports, the study analyzed data from more than 12,000 Americans aged 50 and older, collected between 2006 and 2020 as part of the Health and Retirement Study.
Oi, alongside co-author Cleothia Frazier from Pennsylvania State University, explored how changes in the “Big Five” personality traits—neuroticism, openness, extraversion, agreeableness, and conscientiousness—correlated with both memory impairment and life stressors.
Personality Changes: Aging or Stress?
The researchers found that, on average, older adults exhibited small but consistent declines in all five personality traits over time, regardless of memory impairment. This trend aligns with existing research suggesting that personality tends to become less pronounced with age.
For example, people may become less extraverted or agreeable as they grow older, often withdrawing socially or emotionally.
However, the study also revealed that certain individuals experienced more dramatic changes. Some showed increased neuroticism, struggling to regulate emotions, while others displayed decreased conscientiousness, facing difficulty with planning and achieving long-term goals.
Surprisingly, these changes were not primarily linked to memory impairment. Instead, they were strongly associated with life stressors, such as loss, financial difficulties, or health struggles.
Stress-related events accounted for 25-35% of changes in neuroticism over an eight-year period. These findings suggest that stress—rather than cognitive decline—is often the driving force behind personality changes in older adults.
Rethinking Early Screening for Dementia
Oi emphasized that while personality changes may be connected to early dementia in some cases, they are not definitive indicators of cognitive impairment. “We’re not refuting the relationship between increased neuroticism and the early stages of dementia,” Oi explained.
“We’re just pointing out that not all older adults who have increased neuroticism are in the early stages of cognitive decline.”
He noted that clinicians have begun relying on personality changes as a quick, inexpensive way to screen for Alzheimer’s and other dementias.
However, this approach can be misleading without considering the broader context of a person’s life. Stress, which significantly affects the brain and personality, often mimics signs of cognitive decline.
Oi urged medical professionals to take a holistic approach when evaluating personality changes, considering life circumstances alongside medical assessments. Stress reduction should be a priority, as unchecked stress not only impacts personality but can also elevate the risk of cognitive decline over time.
Addressing Stress and Inequality
The study highlights the need to address systemic stressors that disproportionately affect vulnerable populations. Poverty, discrimination, and health inequities often force individuals to endure chronic stress, which can take a toll on both mental and physical health.
“Imagine working into your 70s or 80s to make ends meet or losing sleep over hospital bills,” Oi said. “These inhumane stressors affect not just day-to-day life but also increase the risks of cognitive decline.”
By addressing these underlying stressors, society can help improve the quality of life for older adults and potentially reduce the risk of dementia. Oi advocates for systemic changes to tackle inequality, along with increased support for individuals facing significant stress.
The Importance of Contextualizing Personality Changes
Oi concluded that personality changes in older adults should not be viewed in isolation. Whether driven by dementia or life stress, such changes indicate “a tension between life and self.” Addressing the root causes—be it Alzheimer’s, financial strain, or other challenges—is crucial for improving cognitive health and overall well-being.
A holistic approach to cognitive health, which prioritizes understanding and addressing stressors, may not only improve early detection of dementia but also help delay its onset.
“If stress is causing people to feel unlike themselves, that should be the first issue addressed,” Oi said. “Personality changes are a sign that something tumultuous is happening. That something, if ignored, can become clinical.”
If you care about Alzheimer’s, please read studies about the likely cause of Alzheimer’s disease and new non-drug treatment that could help prevent Alzheimer’s.
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The research findings can be found in Scientific Reports.
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