Researchers have figured out new ways to identify who is at risk of developing Alzheimer's, an incurable brain disease that affects 5.4 million Americans.
By studying spinal fluid samples and health data from 201 research participants at the Charles F. and Joanne Knight Alzheimer’s Disease Research Center, researchers at the Washington University School of Medicine in St. Louis have shown various biomarkers are reliable predictors of Alzheimer’s even years before symptoms become evident .
The findings, researchers say, provide more proof that scientists can detect Alzheimer's well before the onset of memory loss and cognitive decline.
“We wanted to see if one marker was better than the other in predicting which of our participants would get cognitive impairment and when they would get it,” said Dr. Catherine Roe, research assistant professor of neurology, in a press release. “We found no differences in the accuracy of the biomarkers.”
The researchers evaluated markers such as the buildup of amyloid plaques in the brain, newly visible thanks to an imaging agent developed in the last decade; levels of various proteins in the cerebrospinal fluid, such as the amyloid fragments that are the principal ingredient of brain plaques; and the ratios of one protein to another in the cerebrospinal fluid, such as different forms of the brain cell structural protein tau, according to a press release.
The markers were studied in volunteers aged between 45 and 88. On average, the data available on study participants spanned four years, with the longest recorded over 7.5 years.
The researchers found that all of the markers were equally reliable when it came to identifying people who were likely to experience cognitive troubles later in life and at predicting the point at which their impairments would become noticeable.
The scientists then paired the biomarker data with demographic information, testing to see if sex, age, race, education and other factors could improve their predictions.
“Sex, age and race all helped to predict who would develop cognitive impairment,” Roe said. “Older participants, men and African Americans were more likely to become cognitively impaired than those who were younger, female and Caucasian.”
Roe said future cognitive impairment can be more accurately forecast when biomarkers are used in conjunction with patient characteristics.
“Knowing how accurate biomarkers are is important if we are going to some day be able to treat Alzheimer’s before symptoms and slow or prevent the disease," she said in a press release.
Last year, researchers who are also from the Washington University School of Medicine found that, in patients with early Alzheimer's disease, higher levels of the marker visinin-like protein 1 (VLIP-1) in the spinal fluid were linked to a faster mental decline in the coming years.
In the past, other research has tied walking ability to memory and cognitive decline.
The ultimate goal of all the studies, researchers say, is to identify reliable biomarkers that will one day make it possible to try and treat people well before the onset of Alzheimer's symptoms.