Low psychological wellbeing may raise risk of dementia, study suggests

Lacking purpose in life and having few opportunities for personal growth may increase the risk of developing mild cognitive impairment (MCI), a frequent precursor of dementia, a study suggests.

These aspects of psychological wellbeing noticeably decline two to six years before memory loss and thinking problems are diagnosed, researchers found.

The study adds to mounting evidence linking psychological wellbeing to brain ageing, including the development of dementia.

Researchers tracked 910 people in Illinois in the US for an average of 14 years to assess whether they developed MCI or dementia.

An annual psychological wellbeing assessment of participants included gathering data on purpose in life, positive relations with others, personal growth, self-acceptance and autonomy.

During the follow-up, 29% were diagnosed with MCI. Among this group, 34% were diagnosed with dementia.

The final analysis was based on 229 participants with complete before and after data, including 73 who developed dementia.

Compared with participants who remained “cognitively intact”, those who developed MCI were more likely to have lower levels of psychological wellbeing.

Similarly, compared with those who didn’t develop dementia, those who did were more likely to have a lower level of psychological wellbeing.

The researchers from the US, China and Sweden, whose study was published in the Journal of Neurology, Neurosurgery & Psychiatry, found that people who developed MCI had a faster decline in psychological wellbeing compared with people who were “cognitively intact”.

They had lower wellbeing scores two years before they were diagnosed with MCI, experts found. The researchers also found that people who developed MCI lacked a purpose in life three years before diagnosis, and had lower levels of personal growth six years before diagnosis.

The researchers cautioned that this was an observational study, so no firm conclusions could be drawn about cause and effect. The participants were well educated, which may have introduced selection bias because of the “healthy volunteer” effect.

Most of the participants were also white and female, which may limit the generalisability of the findings, the researchers acknowledged. They also conceded that poorer cognition might influence psychological wellbeing as well as the other way round.

The research team said: “Psychological wellbeing (specifically purpose in life and personal growth) became significantly lower before MCI diagnosis. Reduced psychological wellbeing may serve as a predictor for impaired cognitive function.”

Dr Richard Oakley, associate director of research and innovation at the Alzheimer’s Society, said there was “substantial research evidence” to show that looking after your mental wellbeing and staying socially active throughout your life could help to reduce the risk of developing MCI and dementia.

He added: “This research looked at individuals who were diagnosed with MCI, which can be an early indicator that an individual will go on to develop a type of dementia.

“The results suggest that wellbeing factors, such as feeling a purpose in life and personal growth, are not necessarily an early indicator of dementia but could be an early indicator that someone may go on to develop mild cognitive impairment.”

Further research was required, Oakley said. “At this stage it is not clear whether we can use these wellbeing factors as a predictor of MCI and we need research to demonstrate if tackling these factors might change the trajectory of a decline in memory and thinking skills.”