Dementia: Younger Means Faster

Alzheimers disease may progress faster in younger patients than in older patients

(RxWiki News) Risk of Alzheimer’s disease (AD) increases with age, but the way the disease progresses varies. Some people with AD start having symptoms in their sixties and others much later.

Recent research looked to see if the rate of cognitive decline was different for older versus younger elderly people. 

They found that people under the age of 85 who had cognitive decline showed a faster rate of decline than those over 85. This finding has implications for diagnosis and research for AD.

"Tell your doctor if you're having any memory problems."

Researchers at the University of San Diego, led by Dominic Holland, PhD, enrolled 723 people between the ages of 65 to 90 who either had mild cognitive impairment, AD or were cognitively normal according to standard memory tests.

They then looked at brain images and biomarkers of these patients and compared them to their rate of cognitive decline.

They tested them every six to twelve months for up to three years using magnetic resonance imaging (MRI) and samples of cerebrospinal fluid (the liquid in the brain and spinal cord).

In the MRI, they looked for signs of brain tissue loss that are common in AD. Cerebrospinal fluid was tested for levels of beta amyloid, which forms plaques in AD, and tau proteins, which create tangles in AD.

They found that the younger people in the study, those under the age of 85, showed faster rates of tissue damage in the brain and higher levels of beta amyloid and tau protein in the cerebrospinal fluid. 

The younger people also had faster rates of cognitive decline.

The authors concluded that these findings may be helpful in some ways, but more research is needed to understand the disease process of AD. Age differences seen in this study could represent different forms of the disease – or it could just mean that the disease process that is being influenced by other factors.

They noted that this has implications for both clinical practice and AD research. In practice, people showing the slower progression may be overlooked in diagnosis. In research, clinical trials for treatments may not be able to show a slowed progression if they do not take into account this age issue.

In a recent press release, Dr. Holland said, "The good news in all of this is that our results indicate those who survive into the later years before showing symptoms of AD will experience a less aggressive form of the disease."

This study was published on August 2 in PLoSOne. No conflicts of interest were reported.

Review Date: 
August 2, 2012