Scientists were able to pick out 10 proteins that can predict whether or not people with daily memory and attention problems will be diagnosed with dementia.
These proteins may pave the way for future blood tests to detect Alzheimer's.
As the most common form of dementia, affecting over 5 million people in the U.S. alone, Alzheimer's disease is the target of worldwide research and ample amounts of funding. Yet the efforts and the money have not been enough. No successful treatments are available and researchers predict only an increase in the diagnosis rate.
At this point, doctors and scientists are placing much of their hope on early diagnosis. This is where tests to predict the onset of Alzheimer's or detect it early can make all the difference. Researchers at King's College London and Proteome Sciences, a UK company, conducted the largest Alzheimer's protein study thus far in an attempt to distinguish which proteins might mark the progression from memory loss to full-onset Alzheimer's, before the disease takes over entirely.
"Many of our drug trials fail because by the time patients are given the drugs, the brain has already been too severely affected," says senior author Simon Lovestone, a professor at the University of Oxford. Lovestone stresses the dire need for early diagnosis.
Lovestone and colleagues were able to identify 16 proteins linked to memory loss or Alzheimer's. After narrowing these results with a second test, the scientists found 10 specific proteins with which they could predict the pathway from mild memory loss, as seen in Mild Cognitive Impairment (MCI), to Alzheimer's onset.
MCI is characterized by daily memory and attention impairments and is, in 10% of cases, a precursor to Alzheimer's. However it does not always progress to dementia and often, the cause of these minor memory impairments can be chalked up to an unavoidable and ever-plaguing culprit: stress. Yet many with MCI are misdiagnosed with dementia. Meanwhile, those with fewer or no symptoms of memory loss may have Alzheimer's, or other forms of dementia, but may not be diagnosed until too late. To successfully predict who will and will not be affected by Alzheimer's, knowing the proteins that mark the progression from MCI to dementia is crucial.
The team of researchers examined 1,148 individuals in total; 476 participants in the study had Alzheimer's disease, 220 participants had MCI and 452 were nondiagnosed control participants without any symptoms of dementia and memory loss. The researchers also used MRI brain scans on 476 participants to examine results with more clarity. Their findings, which were published on July 7 in the journal Alzheimer's and Dementia, validated research published earlier this year claiming to have isolated 10 protein markers of Alzheimer's.
While this study allows researchers to focus on specific proteins, it also paves the way for the development of a blood test to identify individuals with MCI that may end up with Alzheimer's diagnoses. The proteins allow for 87 percent accuracy and can predict onset within approximately a year's time. Such blood tests are undergoing preliminary research but are not available for use just yet.
"Detecting the first signs of Alzheimer's could improve clinical trials for new treatments and help those already concerned about their memory, but we're not currently in a position to use such a test to screen the general population," says Eric Karran, director of research at Alzheimer's Research UK.
Hopefully, further validation of this study and future clinical trials using developed blood tests will aid in fighting this disease sooner, rather than later. By 2050, an estimated 135 million people worldwide will have dementia.
