Scientists at McGill University and the Lady Davis Institute for Medical Research in Canada have come up with a blood test that can detect the early stages of Alzheimer's disease. There is currently no accepted blood test for Alzheimer's and diagnosis is based on a series of neurological and psychological tests. The Canadian scientists used a technique called near-infrared biospectroscopy to identify changes in blood plasma. They analysed samples from people with Alzheimer's disease, mild cognitive impairment and from healthy control subjects. They were able to identify people with Alzheimer's with 80% accuracy and also identify people with mild-cognitive impairment, which is often a precursor of Alzheimer's.
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