New Alzheimer’s test raises questions

Scientists have just announced an important breakthrough: a blood test that can determine someone’s likelihood of getting Alzheimer’s disease in the next five years. This test is good news for those of us who would passionately prefer to die before becoming demented, even to the point where we would end our own lives.
If you are 70 or older and “fail” this test, then you will know with a 90-percent degree of accuracy that you will become cognitively impaired in the near future.
The average time to become impaired in this study was 2.1 years. The average life span after showing signs of Alzheimer is ten years.
I believe that preemptive suicide is one reasonable response to impending dementia. For people who agree, however, a major barrier has been pinpointing the right time to act. We don’t want to act too soon, and lose what could have been many good years, but we don’t want to wait until it is too late to act. Some of the first things to go in dementia are awareness of one’s cognitive decline, and executive function, meaning the ability to make a plan and carry it out. Biomarker tests such as this one can be an invaluable tool to address this dilemma.
Once this new test is validated, important policy questions will need to be addressed. Will the test be available only to subjects in clinical trials, to help researchers test the efficacy of new drugs that may prevent or slow the disease? Or should it be available from your physician, like a test for cholesterol or thyroid function?
Unfortunately, that will put many patients in an adversarial position with their doctors, who may be afraid of legal liability if they order a test for a patient who expresses an interest in preemptive suicide. Forcing patients to lie to their doctors is demeaning and counterproductive. But why should doctors control this test at all? Why shouldn’t it be available to anyone who wants it and is willing to pay?