Apparently, the new "Alzheimer's blood test" that Mark Mapstone and colleagues have discussed in Nature is not necessarily the game changer early news reports have made it out to be.
The researchers looked only at 525 people, the people in the study cohort were all 70 or older, and the test detected traces of chemicals associated with Alzheimer's just three years before the people tested developed symptoms of the disease.
The test caught only about 90 percent of the people who developed symptoms of Alzheimer's, and it falsely indicated that 10 percent of the people who stayed healthy would develop Alzheimer's.
So, the test is probably not coming to a private long-term care insurance (LTCI) underwriting lab near you any time soon.
But, what if the researchers do figure out how to develop a version of the test that is to Alzheimer's what a dollar-store pregnancy test now is to pregnancy, and people of all ages can use the test?
If LTCI carriers could use the results from the test, maybe that would make writing profitable coverage for "houses that aren't already on fire" much easier.
People who knew they were going to suffer from at least some degree of dementia in old age could use some combination of private savings, family help and government programs to cope with the known challenges of the future. Maybe they could start early with efforts to make arrangements that would minimize the financial cost of dealing with dementia and maximize their quality of life.
The carriers could focus on spending less to pay richer benefits to the many people who would still be at risk of needing long-term care later in life because of strokes, heart attacks, accidents or many other health problems.
If, on the other hand, kind-hearted lawmakers or regulators prohibited insurers from using the results of the tests, that would eliminate the LTCI market. Even if lawmakers prohibited consumers from taking the tests and lying about the results, of course, smart people would go to a non-U.S. country, take the test under an assumed name, and then, if the results were positive, in a scary way, come back and stock up on private LTCI and related products.
Of course, that kind of LTCI arbitrage situation would last only as long as it took for the insurers to yank their products off the market. As soon as the possibility of that kind of asymmetric access to information existed, insurers would be filing product withdrawal applications as quickly as they could hit the return keys on their computers.