BIOBRIEFPAPER
Blood and spinal fluid tests now help decide who is eligible for new Alzheimer's treatments. A peer reviewed rapid review says the evidence on who they work for, and who they may harm, is too thin.
A peer-reviewed rapid review of 34 studies concludes that blood and spinal-fluid tests now used to help decide who is eligible for new Alzheimer's treatments raise more ethical risks than benefits in the current clinical context, and that the evidence base is too thin to settle those questions.
The review, indexed on PubMed (PMID 42669176) and reported under PRISMA guidelines, screened 10,611 records down to 34 and organized its findings around the four pillars of biomedical ethics. Its authors warn that uncertainty in how these fluid biomarkers perform in underrepresented groups puts three of those pillars at risk: avoiding harm when a test is inaccurate or misused, informed and uncoerced consent, and fair access and fair performance across racial, ethnic, age, and socioeconomic groups.
The authors are blunt that their conclusions are subjective narrative synthesis and that empirical data on benefits and harms is lacking. The implication for anyone being offered, or ordering, a fluid biomarker for treatment eligibility, including for early memory and thinking problems that may or may not progress to Alzheimer's dementia, is to ask how the test performs in their demographic and what the plan is when it returns an unexpected result.