If you had Alzheimer's disease, how soon would you like to know it?
A test that can help doctors diagnose Alzheimer's earlier and more accurately recently was approved by the Food and Drug Administration. But there is little benefit from treatment, which raises a natural question: Is having such terrible knowledge really worthwhile?
We're likely to face more such medical conundrums in the near future as diagnostic technologies and genetic testing far outstrip our ability to cure or prevent the diseases our new techniques reveal.
In the case of Alzheimer's, a definitive diagnosis often isn't possible until an autopsy occurs. But the FDA has approved a new radioactive dye that can reveal suspect amyloid proteins in an Alzheimer's brain under PET scan. Not everyone with amyloid plaques has the disease, but their presence in conjunction with other symptoms can enable earlier and more reliable diagnoses.
The absence of plaques could bring some peace of mind. Or a firm diagnosis could make it possible for patients and families to plan more effectively. But it could also blight the years that remain, dividing a life between a time of Edenic ignorance and the misery of knowing just what's ahead.
The innovative medical tests in our future raise a host of social questions. In the brave new world that is right around the corner, will life or health insurers be allowed to use these tests in setting premiums? Will employers seek this information to head off the legal liability that could arise from, say, hiring a bus driver with a genetic predisposition to heart failure or dementia?
Already, some wonder whether we know too much. "Our increasingly bold discoveries of the secrets of nature," the literary scholar Roger Shattuck has written, "may have reached the point where that knowledge is bringing us more problems than solutions."
Yet the solutions are likely to come, as in the past, from more knowledge still. Besides, no one can hold back the frontiers of discovery.
How much will each of us want to know about our own medical destiny? There are no easy answers, at least until the diseases and predispositions we detect can also be cured.