Researchers found that chronic negative thinking is associated with faster cognitive decline and deposition of harmful brain proteins linked to Alzheimer’s disease.
“Depression and anxiety in mid-life and old age are already known to be risk factors for dementia,” Natalie Marchant, lead author, said in a University College London press release. “Here, we found that certain thinking patterns implicated in depression and anxiety could be an underlying reason why people with those disorders are more likely to develop dementia.”
Marchant said the evidence does not suggest “short-term setbacks would increase one’s risk of dementia.”
She hopes the team's findings are useful in developing strategies to reduce dementia risk by helping people lower their negative thinking patterns.
More than 300 older adults were involved in the study, and over the course of two years, they reported how they typically respond to negative experiences. The questions were geared toward repetitive negative thinking patterns, such as rumination and worry. A portion of participants (113) underwent brain scans measuring deposits of tau and amyloid, two proteins associated with Alzheimer’s disease when they accumulate in the brain.
Study authors concluded that those who demonstrated higher repetitive negative thinking patterns experienced more cognitive decline over a four-year period. These individuals were also more likely to have the harmful brain deposits.
“Our thoughts can have a biological impact on our physical health, which might be positive or negative,” said co-author Dr. Gael Chételat. “Mental training practices such as meditation might help," she said.
While depression and anxiety may necessitate medication (like antidepressants) for some, perhaps meditation could work for others, Dr. Helen Kales, a professor and chair of the psychiatry department at the University of California, Davis, told Healthline.
The researchers hope mindfulness training or targeted talk therapy could lower the risk of dementia, and Marchant and Chételat are working with other European researchers to further investigate whether interventions like meditation could support mental health in older age and thereby help lower dementia risk.
Fiona Carragher, director of research and influencing at Alzheimer’s Society, said most of the study’s participants were already identified as being at higher risk of Alzheimer’s disease, so further research is necessary to see if the same result echoes within the general population.
Some negative thoughts are a normal part of life, Dr. Jacob Hall, neurologist at Stanford Health Care in California, told the outlet. Hall said a positive mindset leads to a higher quality of life, which could in turn reduce health issues.