Blood Test Demonstrates 95% Accuracy in Diagnosing Alzheimer's Disease in Outpatient Clinics

Recent research from Mayo Clinic highlights a significant advancement in Alzheimer's disease diagnosis through a blood test that exhibits 95% sensitivity and 82% specificity. This FDA-approved blood test is designed for use in outpatient memory clinics to aid in accurately diagnosing patients presenting with cognitive impairments, offering a less invasive and more cost-effective alternative to traditional methods like PET scans and spinal taps.

Alzheimer's disease, characterized by memory loss, concentration difficulties, personality changes, and behavioral shifts, profoundly impacts patients and their families. Early and accurate diagnosis is crucial, especially with emerging treatments available for early-stage Alzheimer's, emphasizing the need for accessible diagnostic tools.

The Mayo Clinic study involved over 500 patients aged between 32 and 89 who were undergoing evaluation at the Memory Disorder Clinic in Florida. Participants displayed various cognitive issues, with 56% diagnosed with Alzheimer's disease. The researchers focused on blood plasma biomarkers, specifically measuring levels of proteins Aβ42/40 and p-tau217, which are associated with amyloid plaque buildup—a hallmark of Alzheimer's.

Results showed increased levels of p-tau217 in patients with Alzheimer's, correlating with disease presence and severity. The blood test successfully identified Alzheimer's in 95% of cases with cognitive impairment related to the disease. The findings suggest that plasma p-tau217 could serve as a reliable biomarker for early detection and disease monitoring.

This research opens new avenues for better screening, patient selection for clinical trials, and evaluating treatment responses. The study also emphasizes the importance of considering kidney function, as it influences biomarker levels, to ensure accurate interpretation.

The next phase involves expanding testing to more diverse populations and individuals with preclinical Alzheimer's symptoms. Researchers aim to refine the test further to enhance diagnostic accuracy and applicability in routine clinical practice.

This breakthrough was presented at the American Academy of Neurology Annual Meeting and underscores the potential of blood-based diagnostics in transforming Alzheimer's disease management.

Source: https://medicalxpress.com/news/2025-06-blood-accuracy-alzheimer-disease-diagnosis.html