Now here’s a scientific and epidemiologic conundrum: Suppose you develop a test that will give you advance warning of a fatal disease you can neither treat nor prevent. But that foreknowledge might allow an understanding of the really early aspects of the disease -while it was still asymptomatic- that could eventually lead to a treatment. Especially if the disease, as most are, was potentially more treatable in its early stages. What should you do with the test? You need a lot of people to take the test so you can more appropriately generalize the information obtained and yet you can do nothing for them.  And what are the subjects in the test to do with the information? Suppose it is falsely positive and, despite what the results suggest, despite the worry and possible suicides contemplated, they will not actually get the disease. No test is perfect.

In other words, should you screen a particular population with the test, when the value is not so much for the individual tested as for the knowledge that might eventually be useful to someone else? How ethical is it? How cruel is it..?

People have thought about this, fortunately, and some guidelines were offered in 1968 by the World Health Organization for screening criteria. Among them are the suggestions that, not only should the condition be an important problem, but there should also be a treatment for the condition and an ability to diagnose it accurately. They also suggested the condition should have a latent stage when treatment would be expected to be more efficacious.

The problem I have set forth, of course, is exemplified by the recently announced test for Alzheimer’s Disease. (I have included two articles, the Huffington Post summary being the more easily assimilable of the two.)

http://www.medscape.com/viewarticle/821982?src=iphone&ref=email

http://www.huffingtonpost.co.uk/2014/03/10/dementia-early-detection-blood-test_n_4933188.html

It is obvious that Alzheimer’s disease and dementia are both important health concerns in a time when populations are aging in many countries. It would be helpful to know what facilities might be needed so the appropriate infrastructure could be planned for that particular demographic. But equally, it would be useful to know more about who in that population are particularly at risk so they could be studied. A recent report from the Alzheimer’s Association, for example, suggested that women over 60 are two times as likely to develop Alzheimer’s disease over the rest of their lives as breast cancer:

http://www.alz.org/news_and_events_women_in_their_60s.asp

Perhaps of paramount importance is studying the disease at an early stage to search for the cause. To devise a cure. And yet I can’t help thinking about the helpless laboratory animals in our research facilities, poked, prodded and experimentally assigned… But not for their own good. What constitutes a laboratory animal..?

Under what conditions, then, would it be permissible to undertake such a study? Informed consent is mandatory, of course, but what exactly would the participants be consenting to? To knowing about an inexorable decline in cognitive functioning that would rob them of that which they hold the dearest: themselves? We are our pasts -they are what knit the fabric of our identities into a pattern we and others can recognize from one day to the next. The present is a transient gift that constantly slips behind us so we have to pull it along like a shadow as we walk through time. We collect each present and store it on an accessible shelf like books we’ve read. Without them, we become functionally illiterate. Lost. Wandering endlessly through unmarked time as in a dense mist with no signposts we can see, let alone understand.

That this vision may encompass the tundra that is Alzheimer’s is obviously more pessimistic than may obtain: no doubt it is a condition that varies on a spectrum. But the prospects are not appealing, nor the amplitude of changes likely predictable -and I, personally, would not want to know about it until it has captured me and shrouded my awareness of what I had lost.

I suspect this is the reason for the cautionary statements of the investigators and the thrust of the caveats of the WHO parameters. I’m not sure what to do with the test they describe. It is obviously an important step on the road to understanding dementia and yet… I am reminded of that famous “To be, or not to be” speech by Hamlet in which he talks about death, but describes it in terms the more pessimistic among us might suggest could equally apply to Alzheimer’s disease: