Spinal-Fluid Test Confirmed To Predict Alzheimer's

omnibit writes "The New York Times reports that researchers have found a spinal-fluid test can be 100 percent accurate in identifying patients with significant memory loss who are on their way to developing Alzheimer's disease. The new study included more than 300 patients in their seventies, 114 with normal memories, 200 with memory problems, and 102 with Alzheimer's disease. Their spinal fluid was analyzed for amyloid beta, which forms plaques in the brain, and for tau, another protein that accumulates in dead and dying nerve cells in the brain. Nearly every person with Alzheimer's had the characteristic spinal fluid protein levels."

Comments

100% Accurate, Nearly All of the Time!

[Alphanos]

So, just to clarify, this test "can be 100% accurate", while at the same time "Nearly every person with Alzheimer's had the characteristic spinal fluid protein levels."

That's a pretty neat trick.

Re:100% Accurate, Nearly All of the Time!

[timeOday]

Read it again, because there is nothing in the article that contradicts the claim that "researchers have found a spinal-fluid test can be 100 percent accurate in identifying patients with significant memory loss who are on their way to developing Alzheimer's disease.":

"Nearly every person with Alzheimer's had the characteristic spinal fluid protein levels. Nearly three quarters of people with mild cognitive impairment, a memory impediment that can precede Alzheimer's, had Alzheimer's-like spinal fluid proteins. And every one of those patients with the proteins developed Alzheimer's within five years. And about a third of people with normal memories had spinal fluid indicating Alzheimer's. Researchers suspect that those people will develop memory problems. "

However, the test can only be 100% accurate if the spinal fluid proteins that presage Alzheimer's decrease after full onset.

The fact that not everybody who tested positive developed Alzheimer's during the study is no counter-indicator at all, especially if they kept testing new subjects throughout the trial (i.e. some were only tested recently).

Of course, the usual caveats apply - you can't predict with 100% accuracy who will develop Alzheimer's years from now because some will die first of other causes. And in biology (and medicine), even if your test is correct on the first 10 patients, and the first 100, and 1000, you just know some smart-alec is going to buck the trend eventually :) Biology is just too messy to follow any simple rules all the time. But that doesn't necessarily have a whole lot of relevance to clinical applications.

Not just a test benefit

[Eccles]

Not only does this give an actual test for Alzheimers, it also means that there's a definitive symptom for it. Wipe out the cause of that symptom and maybe you can stop or reverse the progression of this horrible affliction.

My father is already at the moderate dementia stage of this illness, and it's devastating. Not so much for him as it is for my mother.

Re:Thank goodness:

[cgenman]

In her early onset of Alzheimer's, I used to say shocking things about my life to my Grandmother. She'd be surprised, righteously indignant, and secretly curious. She'd ask all sorts of questions. Fifteen minutes later, we'd do it all again.

When I left from these visits, she'd be absolutely glowing. She'd be awake, excited, and extremely happy. And she had no idea what happened. Next time in, I could make the shocking revelations again with the same effect.