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SENSible Question: Beta-Amyloid and Dementia: “Never” is a Very Long Time – SENS Research Foundation

The second group of rational concerns the Times piece raises are social and bioethical ones. One is the worry that people may be denied health or life insurance, or subject to employment discrimination, or required to disclose personal health information on the basis of such testing. These seem like reasonable concerns.

Instead of opposing people’s ability to get information about their own medical risks and the opportunity to access medicines to hold dementia at bay, people and interest groups concerned about these outcomes should be advocating for protecting people’s right to access insurance without discrimination and to keep their medical information private — and above all, to access damage-repair therapies should they prove effective for prevention, in order to let people neutralize their risk while keeping insurance companies’ risk pools in balance.

Another rational-sounding concern in the article is the psychological impact that a diagnosis of “Stage 1 Alzheimer’s disease” based on molecular damage biomarkers might have on people: “People with no memory problems who learn they are positive for abnormal levels of amyloid or tau proteins can suffer from depression, anxiety and thoughts of suicide, studies have found.”

But in fact, the studies reviewed in the paper that the story links under “studies have found” do not support this concern. Most of the reviewed papers are speculations by bioethicists or medical professionals about how people might react to being told they had beta-amyloid or other molecular damage in their brains, or surveys of the public asking them how they think they might react to such a disclosure. And despite the Times’s well-meaning concern, most people who participated in the survey-based studies said they would want to know if they tested positive. One such study with a randomized design found that substantial majorities of people would be willing to participate in a hypothetical study that involved biomarker testing whether they would be told the results or not, with slightly more people expressing willingness to join if they would be told (70%) as if not (61%).

In some of the survey-based studies, a minority of people say they wouldn’t want to get tested because they worry that they would find a positive finding upsetting. But people declining to be tested because they’re worried they about what they might learn is quite different from people actually suffering anxiety or depression in response to a positive finding. And of course, no one is advocating mandatory testing of people who don’t want to get tested, any more than anyone advocates for mandatory cancer screening or mandatory testing for blood pressure.

And when we turn to the four studies where people were actually scanned or spinal-tapped for signs of Alzheimer’s-driving molecular damage, the wave of psychological harms that the Times and its bioethicist sources imagine prove to be grossly overblown. In the largest study, scientists used brain scans to look at beta-amyloid burden and brain shrinkage in people over the age of 65 who were cognitively normal for their age and enrolled in a clinical trial testing the effects of exercise on such damage. More than one in four of the volunteers had such damage evident in their scan. After researchers told people whether or not they had Alzheimer’s-driving molecular damage in their brains, people with brain amyloid detected had no worse depression scores than did those without. And while people with a positive scan expressed a slight increase in anxiety scores upon first being told, their anxiety levels returned to baseline or were actually better than where they started after a six-month followup. The investigators concluded that informing people of their amyloid status “has a low risk of psychological harm.”

A caveat to that finding is that the volunteers in this trial were given counseling about the implications of the test before and after the researchers informed them of their status, which might have helped to allay any psychological distress. One might reasonably worry that outcomes could be less sunny if health systems began offering widespread testing in the community without such counseling.

Rather than grasping at this nuance as a reason to reject testing people who are cognitively normal for their age, those who are concerned for the psychological well-being of people who are tested should work to ensure that such people have similar access to counseling. 23andme has proven that this can be scaled using telemedicine as part of a modestly-priced low-barrier consumer test for the Alzheimer’s risk genetic variant APOE4; there is no obvious reason why it similar counseling could not be bundled with testing for Alzheimer’s-driving molecular damage. In fact, one of the other four studies simply provided test-takers with an informational brochure about the test; the volunteers said they found it useful, and again there was no evidence of psychological distress from receiving the results. (Conversely, the people who tested positive said the result motivated them to adopt more healthy lifestyle habits).

In a third study, people who were tested and their caregivers uniformly expressed relief at their result, whether it was positive or negative. And in one of the smallest studies, this one in  people with MCI rather than people with normal cognition for their age, only two out of eight people who tested positive for beta-amyloid said they suffered emotional distress such as sadness and worry after learning the results. Counterbalancing such distress,

Patients reported that they experienced advantages after the disclosure, such as information about their health status, the possibility of making practical arrangements, medication, enjoying life more, and a positive impact on relationships.

The final thing to say about this concern about the psychological impacts of widespread testing is that to whatever extent people might experience sadness or anxiety upon learning that they have the molecular damage that leads to Alzheimer’s disease in their brains, it seems reasonable to assume that much of that distress would be due to the fact that most people believe that nothing can be done about an Alzheimer’s diagnosis — even the presymptomatic, damage-based “Alzheimer’s Stage 1” diagnosis that the Working Group is proposing.

This fatalism was excessive even at the time that the studies we’ve just reviewed were conducted; there is much less justification for it today, and it would be actively harmful if it were to interfere with the efforts of the Working Group to line up testing and treatment. At the time that the Times article and its cited review article were written, we already had AmyloSENS therapies that slow the slide into darkness for people in the early stages of actual dementia. And the Working Group proposal is an effort to ensure that people who have beta-amyloid or tau aggregates in their brains can initiate treatment with damage-repair therapies while their cognition is still intact, to keep as many people as possible from falling into dementia in the first place.

As we have just seen, the available evidence finds very little psychological harm to people who learn they have Stage 1 Alzheimer’s even in the absence of an effective therapy; how much less of a negative impact will it have when we have such therapies available?

This hand-wringing is reminiscent of some of the social concerns that people raise about greatly-extended lifespans arising from postponing age-related disease and debility with rejuvenation biotechnologies: a crisis in Social Securitycultural stagnationgerontocracy, and so on. The way to prevent this parade of horribles is not to put roadblocks in the way of developing therapies to keep people healthy and prevent them from suffering Parkinson’s, and muscle wasting, and hip fractures, and multiple kinds of blindness. Instead, people concerned about these consequences should work to reform the legal and social structures that have been built up around the assumption that everyone will age, become disabled, and die on a predictable threescore-and-ten schedule.