Can psychological wellbeing predict cognitive impairment?

By Dr. Liji Thomas, MDReviewed by Lily Ramsey, LLMAug 14 2024

A recent study in BMJ Journals examined whether changes in psychological well-being trajectories precede mild cognitive impairment (MCI) and dementia. This could inform the potential role of this measure in predicting dementia and shaping further care in such patients.

​​​​​​​Study: Psychological well-being trajectories preceding incident mild cognitive impairment and dementia. Image Credit: PeopleImages.com - Yuri A/Shutterstock.com

Psychological well-being and dementia risk

There are about 57.4 million people with dementia worldwide, and this may triple by 2050.

This progressive, incurable, and disabling condition lays a heavy burden on families, healthcare systems, and the economy. It is crucial to identify risk factors and implement preventative care in the high-risk population, especially since dementia has a long preclinical window.

Dementia risk is increased among people with poor psychological well-being. However, little is known about how psychological well-being shifts with the development of dementia.

The current study included cognitively normal older adults enrolled in the RUSH Memory and Aging Project. The 910 participants had a mean age of 80, and 77% were female.

All participants were monitored via annual visits for as long as 14 years. The aim was to identify new-onset MCI and dementia.

Ryff’s Scales of Psychological Well-Being were used at each visit to measure six psychological well-being aspects: self-acceptance, autonomy, environmental mastery, life purpose, positive relationship with others, and personal growth.

What did the study show?

Among the 910 participants, 265 (29%) developed MCI. Over time, 89 (33.6%) of the MCI group went on to develop dementia. The MCI group was older and thinner and less likely to be depressed than those who remained cognitively intact.

Psychological well-being and MCI

However, participants with new-onset MCI also showed lower psychological well-being. The decline in psychological well-being was significantly greater both before and after the diagnosis in the group which developed MCI, beginning two years before the diagnosis.

Examining individual components, life purpose and personal growth were also lower, the decline beginning three years and six years, respectively, before the diagnosis of MCI. Autonomy also declined by the time MCI was diagnosed.

There was a more rapid decline in positive relations with others after MCI was diagnosed.

Psychological wellbeing and dementia

Among those who developed dementia, the psychological well-being trajectory before and after the diagnosis did not show significant differences, indicating that mean well-being did not decline before the onset of dementia.

Conclusions

“Psychological well-being (specifically purpose in life and personal growth) became significantly lower before MCI diagnosis.”

There was no change in the psychological well-being trajectories before or after the diagnosis of dementia, showing a lack of predictive value.

As such, psychological support should be provided promptly, and a diagnosis of MCI should be made. Conversely, reduced psychological well-being may predict future cognitive impairment.

The directionality of these associations is unknown, though such links have often been reported earlier. However, participants with greater psychological well-being were less likely to be depressed, to smoke heavily, and were more physically, mentally, and socially active.

Higher well-being is associated with reduced inflammation and better cardiovascular health, reducing the risk of cognitive impairment. All these are common protective factors for dementia as well as mental well-being.

This study corroborates earlier research associating cognitive resilience with better psychological well-being and shows that such resilience may reduce cognitive impairment in Alzheimer’s disease.

The specific deterioration in personal growth and life purpose may indicate that these require more cognitive function than other aspects of psychological well-being and are, therefore, more sensitive to cognitive decline.

The decline in positive relations with others may be due to the lower engagement with social groups after the onset of MCI, triggering a downward spiral.

Further research is required to establish if interventions to improve wellbeing can reduce the risk of cognitive impairment.