Experiencing stressful experiences during middle age or childhood can increase the risk of suffering from Alzheimer’s and neuroinflammation, respectively, according to a study led by the Barcelona Institute for Global Health (ISGlobal), promoted by the ‘la Caixa’ Foundation, and in which the Barcelonaβeta Brain Research Center (BBRC), belonging to the Pasqual Maragall Foundation, has collaborated.
Stressful life events, such as the loss of a loved one, unemployment or facing an illness, trigger both behavioral and psychological responses in us to these objective external threats, and there is growing evidence linking stress with an increased risk of dementia. and cognitive impairment.
The results of the study have been published in Annals of Neurology. The researchers’ goal was to determine whether the accumulation of stressful events throughout life could influence the development of Alzheimer’s-related diseases later in life. To do this, 1,290 volunteers from the ALFA cohort of Barcelona participated who did not have cognitive impairment at the time of the study, but had a family history of Alzheimer’s.
Middle age is a particularly vulnerable stage
Participants were interviewed to quantify the number of stressful events they had experienced. In addition, tests such as lumbar punctures and MRIs were performed to evaluate biomarkers associated with Alzheimer’s. Analyzes showed that the accumulation of stress during middle age was related to higher levels of the β-amyloid protein (Aβ), a key indicator in the development of Alzheimer’s.
“We know that middle age is a period in which pathologies related to Alzheimer’s disease begin to accumulate. It is possible that these years represent a vulnerable period in which experiencing psychological stress can have a lasting impact on brain health,” said Eleni Palpatzis, ISGlobal researcher and lead author of the study.
“The mechanisms by which stressful events affect brain health differ between men and women: accumulation of amyloid protein in men and brain atrophy in women”
The accumulation of stressful events throughout life was linked to higher levels of the β-amyloid (Aβ) protein only in men. In women, on the other hand, it was observed that a greater number of stressful experiences was related to a reduction in gray matter volume, suggesting that stress could have different effects depending on gender.
“Our findings indicate that the mechanisms by which stressful events affect brain health differ between men and women: amyloid protein accumulation in men and brain atrophy in women,” explains Eider Arenaza-Urquijo, ISGlobal researcher and last author of the study. .
Neuroinflammation associated with stress in childhood
The study also found that a higher level of stress in childhood was associated with an increased risk of neuroinflammation in old age. Inflammation is a critical molecular response in neurodegenerative diseases, and these findings are consistent with recent evidence linking childhood trauma to increased inflammation in adulthood.
Finally, the study revealed that stressful events in people with a history of psychiatric illness were associated with higher levels of Aβ and tau proteins, neuroinflammation, and a reduction in gray matter volume, suggesting greater susceptibility to the effects of stress. in this population, possibly due to a lower ability to manage stress.
“Our research highlights the importance of stress in the development of Alzheimer’s and provides preliminary evidence on the mechanisms underlying this effect. However, more studies are required to replicate and validate our initial findings,” concludes Eider Arenaza-Urquijo.
Source: Barcelona Institute for Global Health (ISGlobal)
