A Swedish study suggests blood biomarkers could improve Alzheimer’s assessment in everyday medical care, while professional guidance sets limits on their use.
Blood tests could help family doctors assess Alzheimer’s disease with accuracy approaching that of dementia specialists, potentially expanding access to a clearer diagnosis for people experiencing memory and thinking problems.
Interim findings presented at the Alzheimer’s Association International Conference in July 2026 involved 1,310 patients with mild cognitive impairment or dementia and 165 physicians in Sweden. Researchers compared doctors’ diagnoses and care plans before and after they received results from the PrecivityAD2 blood test.
Among patients assessed in primary care, family doctors’ diagnostic accuracy increased from 65% to 93% after reviewing the results. Specialists independently assessing those same patients achieved 94% accuracy after receiving the blood-test information. A separate specialist-care group improved from 74% to 89%, highlighting why results from different patient groups should be distinguished.
The test measures biomarkers related to amyloid beta and phosphorylated tau, proteins associated with Alzheimer’s disease. In primary care, the results were particularly useful in ruling out Alzheimer’s as the explanation for cognitive symptoms. However, a negative result does not exclude other neurological conditions or remove the need for further assessment.
Separate research is exploring whether p-tau217 can help estimate future cognitive decline in older adults who currently have no noticeable symptoms. Findings presented at the same conference and published in JAMA associated higher levels with greater risk of developing cognitive impairment over subsequent years. Such estimates describe risk rather than an inevitable future diagnosis.
Professional guidance remains central to clinical use. The Alzheimer’s Association’s 2025 blood-biomarker guideline focuses on people with objective cognitive impairment undergoing specialist evaluation. It permits sufficiently accurate tests to support triage or, at higher performance thresholds, substitute for amyloid PET imaging or spinal-fluid biomarker testing. PMC
The guideline also warns that commercially available tests vary in accuracy and must form part of a comprehensive clinical assessment. Its recommendations do not establish routine screening for symptom-free populations.
The Swedish findings suggest blood testing could strengthen the assessment patients receive when they first seek help. Translating that promise into wider practice will depend on appropriate test selection, careful interpretation and access to follow-up care.
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