Stressful life events in middle age could increase the risk of developing Alzheimer's, according to a study.
Researchers at the Barcelona Institute for Global Health (ISGlobal) assessed 1,290 volunteers who were all cognitively unimpaired at the time of the study but had a direct family history of Alzheimer's.
Participants were interviewed by doctors about the number of stressful life events they had experienced, such as the death of a loved one or unemployment.
Lumbar punctures and magnetic resonance imaging (MRI) were then performed to test different biomarkers related to Alzheimer's disease.
Researchers found that the accumulation of stressful events during middle age was associated with higher levels of beta-amyloid protein in the brain, a key marker of Alzheimer's disease.
Eleni Palpatzis, ISGlobal researcher and first author of the study, said: "We know midlife is a period when Alzheimer's disease pathologies start to build up. It is possible that these years represent a vulnerable period where experiencing psychological stress may have a long-lasting impact on brain health."
The team also found that higher levels of stressful experiences in childhood were associated with an increased risk of developing neuroinflammation later in life.
Alzheimer's disease affects around six in every 10 people with dementia in the UK, according to Alzheimer's Research UK.
Previous studies have found that chronic stress and depression could accelerate the onset of the disease.
Eider Arenaza-Urquijo, ISGlobal researcher and last author of the study, said: “Our results suggest that the mechanisms through which life stressors affect brain health in men and women are different: amyloid protein accumulation in men and brain atrophy in women.
“Our study reinforces the idea that stress could play a significant role in the development of Alzheimer's disease and provides initial evidence regarding the mechanisms behind this effect, but additional research is needed to replicate and validate our initial findings.”
