Blood test for Alzheimer’s

Blood test boosts Alzheimer’s diagnosis accuracy to 94.5%, clinical study shows

February 22, 2026
9:38 pm

A protein lurking around in the blood can help with the accurate diagnosis of Alzheimer's disease. In a recent study, researchers from Spain investigated how blood-based biomarkers, such as a protein called p-tau217, affect both the clinical diagnosis of Alzheimer's and neurologists' confidence in their diagnosis.

After following 200 consecutive new patients aged 50 and older who presented with cognitive symptoms, they found that a simple blood test measuring p-tau217 significantly improved diagnostic accuracy in routine clinical practice.

When relying solely on standard clinical evaluation, doctors correctly diagnosed Alzheimer’s in 75.5% of cases, but when incorporating blood test results, diagnostic accuracy increased to 94.5%. The findings are published in the Journal of Neurology.

Blood test boosts Alzheimer’s diagnosis accuracy to 94.5%, clinical study shows

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