Providers witness this gap in their everyday practice
- Ambiguous symptoms (depression, sleep disorders, medication side effects, delirium, vascular disease, sensory loss) can mimic, mask, or contribute to neurodegenerative disease
- Standard cognitive tools can confirm impairment in the patient but cannot reliably pinpoint the clinical cause of that impairment and are also insensitive to mild cognitive impairment
- PET scans and CSF testing are costly and not always accessible for patients, which can delay downstream specialty evaluation and treatment decisions
An accessible blood test for Alzheimer’s disease biomarkers can help bridge this diagnostic blind spot by providing objective evidence of AD-related pathology.
Once cognitive impairment is significant enough to be observed through clinical assessment tools, beta-amyloid and phosphorylated tau (p-tau) proteins—both AD biomarkers—may have already been increasing. But blood-based biomarker testing can help identify these microstructural changes in the brain.1
Why it matters: Clinical value of blood testing for Alzheimer’s disease biomarkers in primary care
When cognitive screenings suggest impairment but don’t clearly indicate cause, testing for multiple blood-based Alzheimer’s disease biomarkers can more reliably demonstrate quantifiable evidence of amyloid positivity. This helps providers act with greater confidence in 4 clinically meaningful ways.
1. Clarifying the results of cognitive screenings
A positive cognitive screening questionnaire simply indicates the presence of cognitive impairment. Meanwhile, blood-based Alzheimer’s disease biomarkers help assess whether AD pathology is a likely contributor to that impairment. This is an especially useful distinction in mild cognitive impairment (MCI) or early dementia, when functional changes may be subtle and clinical assessment can be unreliable.
2. Improved access to answers
For patients with limited or no access to more definitive diagnostic testing, such as PET and CSF, a blood-based biomarker test may be a more affordable—and significantly less invasive—option that bears comparably reliable results.
3. Efficient triage to specialty care and testing
Blood testing for Alzheimer’s disease biomarkers can help clinicians prioritize who needs and is most likely to benefit from expedited referral, advanced imaging or CSF testing, or evaluation for disease-modifying therapies (DMTs) that require evidence of amyloid pathology.
4. Timelier interventions
Earlier definition around a patient’s cognitive status allows for earlier intervention such as counseling and care planning, medication audits to avoid therapies with cognitive side effects, and targeted management of associated risk factors (sleep, depression, hearing, etc).
