Blood tests improve Alzheimer's detection in Down syndrome patients

New blood tests that detect early changes associated with Alzheimer's disease are making diagnosis easier and accessible to more patients, since they are less invasive than the brain scans or spinal taps typically used for a definitive diagnosis. Identifying the condition in its earlier stages means drugs that slow progression may have the chance to provide greater benefit.

Alzheimer's incidence is dramatically higher in people with Down syndrome. Yet Lumipulse G p-tau217/β-Amyloid 1-42, the blood test approved by the Food and Drug Administration in 2025 to aid in the diagnosis of Alzheimer's disease, is not available to them because it hasn't been studied in that population.

Scientists at the USC Epstein Family Alzheimer's Therapeutic Research Institute aim to change that. A new USC-led study in the journal Communications Medicine is the first to engage participants with Down syndrome to evaluate Lumipulse G p-tau217 and PrecivityAD2, a second blood test already in wide use for research. The researchers found that both are effective in detecting Alzheimer's pathology in this population.

These blood tests are revolutionizing the field. Our work is one step toward making them available to people with Down syndrome. We're encouraging clinicians to use the tests to help families understand the basis for symptoms they might be observing."