[This abstract first appeared in: Dementia: the Latest Evidence Newsletter RWHT Volume 1 Issue 7 February 2011].
Diagnosis of Alzheimer’s disease currently involves cognitive tests and the exclusion of other causes through brain imaging. It can only be confirmed by looking at changes in the brain after death.
A new technique for a blood test to detect Alzheimer’s disease may soon be on the way. The new method involves screening the blood for antibodies. The technique involves passing blood samples over special slides coated with a synthetic substance designed to identify the antibodies. This test was first developed using genetically modified mice and then refined on Alzheimer’s disease in humans. Raised levels of two antibodies have been found to occur in the blood of people with Alzheimer’s disease but not in unaffected people.
Note: This technique may lead to blood tests for conditions such as Alzheimer’s disease, but the research is at an early stage. The study did not determine how early in the course of developing Alzheimer’s disease the antibody changes could be detected, so it is (as yet) unclear whether the test could ever detect early-stage Alzheimer’s disease as some newspapers have suggested prematurely.
Alzheimer’s blood test shows promise. NHS Choices, January 7th 2011.
Reddy, MM. Wilson, R. Wilson, J. [et al] (2011). Identification of Candidate IgG Biomarkers for Alzheimer’s Disease via Combinatorial Library Screening. Cell, January 7th 2011, Vol.144(1), pp.132-142.