Can changes in behavior predict Alzheimer’s?

A new study finds that behavioral changes can be an early predictor of Alzheimer’s disease even before memory problems show up.

Researchers followed nearly 2,500 people. who were age 50 and older, who were not reporting any memory problems. They were then tracked for the next seven years.

Just over 1,000 of those participants continued to be free of memory problems. That group was then compared with the 1,200 people who who did eventually develop dementia.

Those who developed dementia also showed significant changes in their moods like irritability, depression, apathy and appetite swings much sooner than those who didn’t develop dementia.

“While earlier studies have shown that an estimated 90 percent of people with Alzheimer’s experience behavioral or psychological symptoms such as depression, anxiety and agitation, this study suggests that these changes begin before people even have diagnosable dementia,” said study leader Catherine M. Roe, PhD, of Washington University School of Medicine in St. Louis, in a news release.

These early behavioral changes were significant. “Those who developed dementia were more than twice as likely to develop depression sooner than those without dementia and more than 12 times more likely to develop delusions than those without dementia,” the study found.

The results were published in the online issue of Neurology, the medical journal of the American Academy of Neurology.

Alzheimer’s disease, the sixth leading cause of death in the U.S., has traditionally only been identified at the onset of symptoms, such as memory loss, behavior changes or difficulty thinking clearly.

Researchers can’t say if this is a cause and effect situation until more studies are done.

“We still don’t know whether depression is a response to the psychological process of Alzheimer’s disease or a result of the same underlying changes in the brain,” she said. “More research is needed to identify the relationship between these two conditions.”