Ideal Candidates for Alzheimer’s Disease Blood Testing?
Experts agree that blood tests represent a convenient and scalable option to address the anticipated surge in demand for biomarker testing with the availability of disease-modifying treatments. For now, however, they are not for all older adults worried about their memory.
“Current practice should focus on using these blood biomarkers in individuals with cognitive impairment rather than in those with normal cognition or subjective cognitive decline until further research demonstrates effective interventions for individuals considered cognitively normal with elevated levels of amyloid,” the authors of a recent JAMA editorial noted.
At Mount Sinai, “we’re not starting with stone-cold asymptomatic individuals. But ultimately, this is what the blood tests are intended for — screening,” Elahi noted.
She also noted that Mount Sinai has a “very diverse population” — some with young onset cognitive symptoms, so the entry criteria for testing are “very wide.”
“Anyone above age 40 with symptoms can qualify to get a blood test. We do ask at this stage that either the individual report symptoms or someone in their life or their clinician be worried about their cognition or their brain function,” Elahi said.
Ethical Considerations, Counseling
Elahi emphasized the importance of counseling patients who come to the clinic seeking an Alzheimer’s disease blood test. This should include how the diagnostic process will unfold and what the next steps are with a given result.
Elahi said patients need to be informed that Alzheimer’s disease blood biomarkers are still “relatively new,” and a test can help a patient “know the likelihood of having the disease, but it won’t be 100% definitive.”
To ensure the ethical principle of “do no harm,” counseling should ensure that patients are fully prepared for the implications of the test results and ensure that the decision to test aligns with the patient’s readiness and well-being, Elahi said.
Edelmayer said the forthcoming clinical practice guidelines will provide “evidence-based recommendations for physicians to help guide them through the decision-making process around who should be tested and when. In the meantime, the Alzheimer’s Association urges providers to refer to the 2022 appropriate use recommendations for blood tests in clinical practice and trial settings.”
Mielke has served on scientific advisory boards and/or having consulted for Acadia, Biogen, Eisai, LabCorp, Lilly, Merck, PeerView Institute, Roche, Siemens Healthineers, and Sunbird Bio. Edelmayer and Elahi had no relevant disclosures.
A version of this article appeared on Medscape.com.