A UK research team is poised to begin a new study funded by the Alzheimer's Society to investigate chronic stress as a risk factor for developing dementia.
Anne Corbett, research manager for the Society told the press on Tuesday that the researchers, who will be led by Clive Holmes, Professor of Biological Psychiatry at the University of Southampton, will be investigating the role that chronic stress plays in the progression of Mild Cognitive Impairment (MCI) to Alzheimer's Disease.
MCI is a recent term used to describe the signs people show when they begin to experience thinking and memory problems, but do not actually have dementia.
Alzheimer's Disease is the most common type of dementia, and is where the chemistry and structure of the brain changes, causing brain cells to perish. About 60% per cent of people with MCI are known to go on to develop Alzheimer's Disease.
A lot of research has been done on the link between stress and diseases like heart disease, diabetes, cancer and multiple sclerosis, showing that chronic stress can speed up the progression, or make the symptoms worse. However, surprisingly little research has been done on the link between stress and MCI or Alzheimer's.
"We feel this is a really important area of research that needs more attention. The results could offer clues to new treatments or better ways of managing the condition."
"It will also be valuable to understand how different ways of coping with stressful life events could influence the risk of developing Alzheimer's Disease", she added.
By better understanding how stress, something everyone experiences, might be a risk factor for Alzheimer's, including what the underlying biology might be, the researchers hope to offer new information that can help develop better psychological treatments and drugs that can be used earlier in the progression of the disease.
Holmes said there is a lot of variability in how quickly the progression from MCI to Alzheimer's happens, for some people the progression is slow, for others it is much faster. But we know from other studies that one possible factor is stress.
"That could be driven by a big change – usually negative – such as a prolonged illness, injury or a major operation," said Holmes.
"We are looking at two aspects of stress relief – physical and psychological – and the body's response to that experience. Something such as bereavement or a traumatic experience – possibly even moving home – is also a potential factor," he explained.
For the study, Holmes and colleagues will be observing 140 volunteers aged 50 and over who have MCI, assessing their levels of stress and any progression to dementia over an 18 month period.
The researchers will compare the data they collect on this group with that of 70 other people, the "controls", who do not have MCI.
At the start of the study, all the participants will complete tests of memory and thinking skills and fill in questionnaires that help researchers assess personality type, style of coping with stressful events, and their perceived mood and level of social support.
Then at the end, 18 months later, they will repeat these assessments, so the researchers can see how many progress from MCI to Alzheimer's Disease, and also record any stressful life events.
The participants will also give blood and saliva samples every six months, from which the researchers will be able to trace any biomarkers of stress. Stress affects the immune system, and this can be tracked in the blood samples. Saliva samples are used to measure levels of cortisol, a chemical that the body releases in response to chronic stress.
The study will be funded by one of six grants, worth a total of £1.5 million, that the Alzheimer's Society is awarding to find a cause, cure and way to prevent Alzheimer's Disease.