The stress of being a worrywart may more than double your chances of developing Alzheimer's disease, according to new research.

The study showed that older people prone to constant worry were 2.4 times more likely to develop Alzheimer's disease (search) over the next few years than nonworriers.

The link between distress and Alzheimer's disease appears to be stronger in whites than in African-Americans.

Researchers say the results are in line with the only previous study to look at the relationship between being prone to distress or worry and Alzheimer's disease.

That study, involving a group of clergy members, also suggested that constant worry increased the risk of Alzheimer's disease. Researchers say longer-term studies are needed to fully understand the nature of this relationship.

Worry Raises Alzheimer's Risks

In the latest study, which appears in the Jan. 25 issue of Neurology, researchers interviewed a group of more than one thousand healthy older adults in Chicago about their tendencies to worry and feel distressed.

They examined the study participants three to six years later to see if they developed Alzheimer's disease.

During the follow-up period, 170 people developed Alzheimer's disease. Researchers found that people who were prone to distress and worry were 2.4 times more likely to develop Alzheimer's disease than someone who was not prone to worry.

Specifically, the study showed that each point on the distress-proneness scale increased the odds of having Alzheimer's disease by 6 percent.

Symptoms of depression (search) have also been associated with a higher risk of Alzheimer's disease, but when researchers took these worry-related symptoms into account the association between worry and Alzheimer's disease remained strong.

However, the link between worry and Alzheimer's disease was less robust among African-Americans.

Researchers say older African-Americans may have developed personal or social traits that help reduce psychological distress or its negative effects on health, but more study is needed to explain this.

By Jennifer Warner, reviewed by Brunilda Nazario, MD

SOURCE: Wilson, R. Neurology, Jan. 25, 2005; vol 62: pp 380-382.