Blood Test for Alzheimer’s Disease
New Test can Diagnose Disease Before the Symptoms are Detected
A blood test which is able to diagnose and identify Alzheimer's disease and other dementias has been developed in the USA.
Researchers from a team based in the USA and also European universities have found a blood test that can diagnose Alzheimer’s disease before the individual has shown any symptoms. Up to now, the diagnosis of Alzheimer’s disease has often proved to be inconclusive. But now, the first trials of this test have shown that the test can identify the disease with 90% accuracy.
How the test works
The human brain controls many of our bodies’ functions by producing chemical messengers which help to keep the brain informed about its functioning. Using this observation, the research team worked to study the nature of the chemical communication in order to identify the first stages of Alzheimer’s disease.
A lead scientist from the study, Tony Wyss-Coray said, “Our technology enables us to ‘listen’ to the chatter of cells communicating with each other and determine if there’s anything abnormal.”
The researchers measured levels of 120 proteins functioning as chemical messengers between the blood cells, brain cells, and cells of the immune system. They found that 18 of these chemicals indicated different concentrations in the blood of people who had Alzheimer’s disease.
They concluded that the levels of these proteins alter when the first stages of Alzheimer’s disease start to develop. These become labels or ‘biomarkers’ of the presence of the disease.
The 90% conclusion came as a result of the testing of early blood samples from individuals who had gone on to develop Alzheimer’s disease. The test correctly identified eight of the nine cases studied.
The test can also distinguish between other dementias and Alzheimer’s disease, and it can also predict whether or not mild confusion (MCI) will lead to Alzheimer’s disease.
The test is being researched further, and the company Satoris is developing it for further trials this year.
Reference:
Ray S, Britschgi M et al, Classification and prediction of clinical Alzheimer’s diagnosis based on plasma signalling proteins. Nat. Med.2007 Nov; 13(11):1359-62.
