Having high levels of a fat in the blood may increase someone's risk of developing Alzheimer's disease, a U.S. study suggests.

Researchers are searching for better ways to screen, prevent and treat the mind-robbing disease that is projected to increase in prevalence worldwide.


Scientists are looking for an accurate blood test to predict risk of Alzheimer's risk. (Eliseo Fernandez/Reuters)

Wednesday's issue of the journal Neurology includes a study on a biomarker in the blood that seems to predict the development of Alzheimer’s over the next decade.

In the study, 99 women in the U.S. who were aged 70 to 79 and free of dementia when the study began had their blood tested.

Investigators were checking levels of serum ceramides, a fatty compound found throughout the body that is associated with inflammation and cell death.

Over the nine year study, 27 women developed dementia and 18 of those were diagnosed with probable Alzheimer's disease.

Women who had the highest levels of the biomarker were 10 times more likely to develop Alzheimer's disease than women with the lowest levels, study author Michelle Mielke, an epidemiologist with the Mayo Clinic in Rochester, Minn., and her co-authors found.

"In this population-based sample of older women, high serum ceramide levels were associated with an increased risk of all-cause dementia independent of age, blood glucose and body mass index," the study authors concluded.

The relationship between the biomarker and Alzheimer’s was stronger than for all-cause dementia.

"These findings suggest that high levels of serum ceramides increase the risk of developing Alzheimer's disease."

Accuracy, cost and convenience key

It's also possible that low levels of the biomarker reduce the risk rather than high levels being harmful or that changes in the biomarkers may be a better indicator of progression, the researchers said.

"These findings are important because identifying an accurate biomarker for early Alzheimer's that requires little cost and inconvenience to a patient could help change our focus from treating the disease to preventing or delaying it," said Valory Pavlik of the Alzheimer's Disease and Memory Disorders Center of Baylor College of Medicine in Houston, who wrote a journal editorial accompanying the study.

Pavlik called the study "compelling" because of its design, rigorous methods and consistency with preliminary research into the role of ceramides in cognitive decline.

"We must temper our enthusiasm by recognizing the limitations of this study, which include a small sample size of women only and a single baseline measurement of the biomarker," Pavlik wrote.

The study was funded by the U.S. National Institute on Aging, the U.S. National Institute of Neurological Disorders and Stroke and the Johns Hopkins Older Americans Independence Center.