Swedish researchers found a blood test can diagnose Alzheimer's disease with a 91% accuracy — about 20% higher than dementia specialists.
The study, published July 28 in JAMA, used data from 1,213 patients undergoing cognitive evaluation in primary and secondary care between February 2020 and January 2024. Each patient underwent a blood test and an evaluation by a dementia specialist and primary care physician.
The study found the mass spectrometry blood test had a 91% diagnosis accuracy rate, compared to 61% for primary care physicians and 73% for dementia specialists. The blood test's accuracy was largely driven by its ability to detect and measure p-tau217, a compound that is specific to Alzheimer's, according to a July 28 editorial on the study.
"These tests can be used to enhance the ability of clinicians to accurately identify individuals with cognitive impairment and dementia due to Alzheimer disease," the editorial authors wrote. "Accurate and early diagnosis of [Alzheimer's] disease is increasingly important because of the new era of monoclonal antibodies targeting amyloid reduction in the brain."