Chronic distress linked to higher dementia risk

NEW YORK, Feb 17 (Reuters) Older adults who are prone to emotional distress may have an increased risk of developing dementia, a new study suggests.

Researchers found that older men and women with chronic distress were more likely than their peers with low distress levels to develop dementia before they died. However, distress was not related to the plaques, tangles and other brain changes that mark Alzheimer's disease and other forms of dementia.

The implication, researchers say, is that persistent distress may contribute to dementia in some unique, as yet unrecognized way.

They report the findings in the journal Psychosomatic Medicine.

The study included a group of older Catholic priests and nuns whose health has been followed since 1994. At the outset, they completed questionnaires on several measures of chronic distress -- their levels of neuroticism, tendency toward anxiety and symptoms of depression.

During the study period, 219 study participants died and had brain autopsies, including 95 who'd been diagnosed with dementia before their deaths. Nearly all brain autopsies, however, showed some evidence of the abnormalities that mark dementia -- most often the protein deposits known as plaques and tangles.

The researchers found that while higher levels of distress were related to a higher risk of dementia, distress was not related to the degree of dementia-related brain pathologies.

This suggests that chronic emotional distress may contribute to dementia through some ''distinctive'' mechanism, according to study chief Dr Robert S Wilson of Rush University Medical Center in Chicago.

It's not clear what that mechanism might be, he told Reuters Health, but animal research has pointed to some possibilities.

Animals subjected to stressful conditions show brain atrophy (wasting) and other changes in certain brain areas, along with impairments in learning and memory -- suggesting that persistent emotional distress could have similar effects in people.

If future research shows that it does, that could open up new ways to slow or lower the risk of dementia.

''If these animal studies are correct, this could be of immense practical use,'' Wilson said.

There are ways to potentially lessen the consequences of emotional distress on the brain, he explained, from antidepressant medication to exercise.

Reuters BDP DB0907