Biomarkers alone don’t mean Alzheimer’s disease is present, Elizabeth Tracey reports

Podcast: Download (Duration: 1:04 — 1.5MB)

Subscribe: RSS

Will an FDA cleared blood test for Alzheimer’s disease ease or complicate diagnosis? Clearly in approving the test the FDA hopes for the former, yet the complete picture is more complex than that, says Abhay Moghekar, a blood biomarkers expert and a neurologist at Johns Hopkins.

Moghekar: In blood these markers are present at very low concentrations so technology to advance enough we needed good antibodies to detect this in blood. So the blood test is reflecting amyloid pathology quite reliably but again we need to not forget that Alzheimer's disease is not just the presence of amyloid, it's the presence of amyloid, it's the presence of tau tangles and more importantly it's the presence of neurons and synapses degenerating that are actually closely linked to the clinical manifestations and that's why you may have people who have amyloid in their brain and even early tau deposition in their brain and may they may be cognitively completely normal.   :31

So in the absence of symptoms of dementia taking this test is not appropriate, Moghekar states, since it may raise anxieties that are unfounded. It is only within a complete assessment by an expert that the test will have utility. At Johns Hopkins, I’m Elizabeth Tracey.