Youth and midlife stress events linked to increased dementia risk in later life, study finds

According to a new study, stressful life events like divorce or the loss of a loved one increase a person's chance of dementia in later life. But only if the traumatic experience occurred during youth or in middle age.

The research, published in Annals of Neurology, comprised 1,290 adults who were at high risk of acquiring Alzheimer's disease. The researchers examined 18 stressful life events and determined when they occurred in people's lives.

A subgroup of the group (393 people) had their spinal fluid samples taken to look for unusual proteins known as tau and amyloid thatare linkedto Alzheimer's disease. They also measured the amount of grey matter and searched for indicators of brain inflammation, which is assumed to be a factor in the illness.

Although the researchers discovered that stressful life experiences between childhood and midlifewere linkedto aberrant amyloid and tau, two "biological markers" of Alzheimer's disease, theywere notlinkedto losses in grey matter.

The presence of Alzheimer's disease markers may imply that stress has a particularly significant influence on chemicals and reactions in the brain during childhood and middle age. Midlife is when Alzheimer's indicators begin to accumulate in the brain, which might explain why it is also a susceptible stage.

Total stressful life experiences were similarly linked to amyloid biomarkers, brain inflammation, and reduced grey matter, but only in people with a history of psychiatric problems.

Thismight be because people with mental health concerns are more sensitive to the adverse effects of stress. It's also possible that people who have gone through certain stressful life situations are more prone to develop a psychiatric disorder. In either case, people who encounter both may face an elevated danger. Total stressful life experiences were not associated with Alzheimer's disease indicators in all individuals.

These findings imply that some periods or settings amplify the effects of stressful life events on the development of Alzheimer's disease-related brain alterations, at least in individuals who are predisposed to the disease.

There are certain limits to the results. The researchers depended on participants to recall what and when stressful situations occurred, often several years later.

(With inputs from agencies)