Question Can a blood test based on the ratio of plasma phosphorylated tau 217 (p-tau217) relative to non–p-tau217 (expressed as percentage of p-tau217) combined with the amyloid-β 42 and amyloid-β 40 plasma ratio (the amyloid probability score 2 [APS2]) accurately identify Alzheimer disease in primary care and secondary care when prospectively applying predefined biomarker cutoff values?
Findings There were 1213 patients undergoing cognitive evaluation in primary or secondary care. The APS2 had high diagnostic accuracy (range, 88%-92%) for detecting Alzheimer disease pathology in both primary and secondary care. Dementia specialists identified clinical Alzheimer disease with a diagnostic accuracy of 73% vs 91% using the APS2 and primary care physicians had a diagnostic accuracy of 61% vs 91% using the APS2.
Meaning This blood test (the APS2) had high diagnostic accuracy for identifying Alzheimer disease among individuals with cognitive symptoms in primary and secondary care, providing superior performance compared with the diagnostic accuracy after standard clinical evaluation (not using Alzheimer disease biomarkers).
More on Blood Biomarkers to Detect Alzheimer Disease in Primary Care and Secondary Care via JAMA.
Learn more on the significance of An Experiment on a Bird in the Air Pump by Joseph Wright of Derby via Wikipedia.
Family Medicine Residency Site: Abbotsford-Mission 