Repeated negative thinking associated with amyloid and tau deposition, increased dementia risk
Repeatedly engaging in negative thinking is linked to future cognitive decline and an increased likelihood of protein deposition associated with Alzheimer’s disease, according to research published Sunday.
In fact, among the more than 100 participants that underwent a PET scan as part of the study published in Alzheimer’s & Dementia, those who demonstrated higher repetitive negative thinking (RNT) patterns were more likely to have amyloid and tau deposits in their brain.
Investigators say such thinking should be analyzed further as a risk factor for dementia, and believe their findings can help inform strategies to mitigate negative thinking patterns.
"Taken alongside other studies, which link depression and anxiety with dementia risk, we expect that chronic negative thinking patterns over a long period of time could increase the risk of dementia,” Natalie Marchant, PhD, with University College London’s Department of Psychiatry, said in a statement. “We do not think the evidence suggests that short-term setbacks would increase one's risk of dementia.”
For the research—supported by funding from the Alzheimer’s Society—Marchant and colleagues studied 292 people over age 55 who were part of a larger Alzheimer’s disease study, and 68 adults from a separate cohort.
During a two-year period, patients answered questions indicating how they think about negative experiences, focusing on RNT patterns such as how they internalized the past and their worries about the future. Additionally, the groups completed questionnaires related to anxiety and depression.
Results showed that those who exhibited higher repeated negative thought patterns experienced higher levels of cognitive decline over a four-year timespan, as well as memory declines. And among the 113 individuals who underwent a PET brain scan, those with more of these repetitive thoughts were more likely to have amyloid and tau deposits in their brain—a known factor in Alzheimer’s disease.
The authors pointed out that depression and anxiety were also associated with cognitive decline, but not with amyloid or tau deposition.
“Understanding the factors that can increase the risk of dementia is vital in helping us improve our knowledge of this devastating condition and, where possible, developing prevention strategies,” Fiona Carragher, director of Research and Influencing at the Alzheimer's Society, said in the statement. “The link shown between repeated negative thinking patterns and both cognitive decline and harmful deposits is interesting although we need further investigation to understand this better.”