Blood Test Boosts Alzheimer’s Diagnosis Accuracy in Primary Care: AAIC 2026 Study

New research indicates that blood-based biomarker tests significantly improve diagnostic precision for primary care physicians, reaching levels previously limited to specialized clinics. Blood test results allow primary care physicians to diagnose Alzheimer’s disease with nearly the same accuracy as specialists, according to data reported at the Alzheimer’s Association International Conference (AAIC) 2026. In a real-world study involving more than 1,300 patients and 165 physicians, researchers found that a blood-based biomarker test improved the accuracy of Alzheimer’s diagnosis in both primary and specialty care settings. The test measures amyloid beta and phosphorylated tau, which are abnormal brain proteins associated with the disease. The interim results included 1,310 patients with mild cognitive impairment or dementia in Sweden. Among those evaluated in primary care, physicians’ diagnostic accuracy rose from 65% before receiving blood test results to 93% after. Specialists saw their diagnostic accuracy rise from 74% to 89% after receiving the results.