Families in 2026 have two meaningful new tools: blood tests that can help identify Alzheimer's-related amyloid and drugs that can slow early-stage decline in selected patients. Neither provides a stand-alone diagnosis or a cure, so families must weigh clearer evidence and slower decline against uncertainty, safety risks, and treatment burden. Amyloid plaques are abnormal protein deposits associated with Alzheimer's disease. The new tests and treatments apply to specific people with cognitive symptoms—not to routine screening of healthy adults or treatment at every disease stage.
Medical information disclaimer: This article is for general educational purposes only and does not provide medical advice, diagnosis, or treatment. Always consult a physician or other qualified health professional about symptoms, medications, tests, or treatment decisions.
Table of Contents
- What can the new blood tests tell you?
- When does blood testing make sense?
- What benefit can treatment realistically provide?
- How demanding and risky is treatment?
- Can Medicare coverage affect the decision?
What can the new blood tests tell you?
The FDA-cleared Lumipulse blood test can help detect Alzheimer's-related amyloid plaques in adults 55 and older who have symptoms and receive specialty care. In a 499-sample study, its positive and negative predictive agreement was 91.7% and 97.3%, respectively, according to the FDA clearance announcement. Those results make blood testing useful, but not conclusive. False positives and false negatives remain possible.
A clinician must interpret the result alongside the person's symptoms and clinical assessment, adding other tests when needed. Roche's FDA-cleared Elecsys pTau181 test serves a different role. It is an initial primary-care aid for adults 55 and older with cognitive complaints, helping identify people unlikely to have Alzheimer's-related amyloid pathology. It does not confirm or rule out Alzheimer's by itself.
When does blood testing make sense?
A blood test is most useful when its result will change the next step. It may help a clinician decide whether a symptomatic person should undergo further evaluation or be referred to specialty care.
A practical testing pathway is: Do not treat a commercially available result as a diagnosis without clinical interpretation. Lumipulse is not cleared for population screening, while Elecsys pTau181 is designed as an initial aid rather than a definitive answer.
- Start with the person's cognitive complaints and a clinical assessment.
- Confirm that the test fits the person's age, symptoms, and care setting.
- Ask whether a positive or negative result would lead to additional testing.
- If treatment is under consideration, determine how the care team will confirm amyloid pathology.
What benefit can treatment realistically provide?
Leqembi, or lecanemab, and Kisunla, or donanemab, are anti-amyloid drugs. Both are approved for people with confirmed amyloid pathology who have mild cognitive impairment or mild Alzheimer's dementia. In Leqembi's pivotal 18-month trial, people receiving the drug declined 0.45 points less on CDR-SB, the trial's measure of decline, than those receiving placebo.
That represented 27% less decline—not recovery or a halt to progression—according to the revised FDA label. In Kisunla's 1,736-person trial, treatment reduced 76-week CDR-SB decline by 0.70 points compared with placebo, according to the FDA approval notice. Because these figures come from separate trials with different time frames, the raw numbers do not establish that one drug works better.
How demanding and risky is treatment?
Both drugs can cause amyloid-related imaging abnormalities, or ARIA, which include brain swelling and bleeding. People with two copies of the ApoE ε4 gene face a higher ARIA risk, so this genetic information can materially affect the treatment decision. Leqembi requires a baseline MRI and additional MRIs before the third, fifth, seventh, and 14th infusions. Its label recommends ApoE testing before treatment so patients can discuss their individual risk.
Kisunla is infused every four weeks. It also requires a baseline MRI and early-treatment MRI monitoring. Its label permits stopping treatment after an amyloid PET scan shows that plaques have fallen to minimal levels. Before agreeing to treatment, ask the center to explain:.
- The expected benefit for this person's stage of disease.
- The ApoE testing decision and what each result would mean.
- The MRI and infusion schedule.
- How the center will respond if ARIA develops.
- Whether the family can sustain repeated visits and monitoring.
Can Medicare coverage affect the decision?
Medicare's national policy covers anti-amyloid monoclonal antibodies only under defined conditions. The beneficiary must have mild Alzheimer's-stage disease and confirmed amyloid pathology, with treatment provided through qualifying CMS-approved studies or registries or NIH-supported trials, as described in CMS National Coverage Determination 200.3.
This makes the treatment center part of the eligibility question. Before scheduling extensive testing, ask whether the center participates in an applicable registry or study and can provide the required treatment and MRI monitoring. Bring one written question to the first appointment: "If testing confirms amyloid, what treatment decision would this result allow us to make?" The answer can prevent a blood test from becoming an isolated result with no clear next step.
