Over the past years, Swedish researchers at Memory Clinic of Skåne University Hospital have been working on improving the accuracy of diagnosing dementia due to Alzheimer disease (AD) by developing an innovative blood test that will soon be available in Sweden and Finland.
One in 5 women and 1 in 10 men develop dementia due to AD. Individuals with cognitive symptoms are first seen in primary care, with a minority being referred to secondary care. However, symptomatic AD is misdiagnosed in 25% to 35% of patients treated at specialized clinics with probably worse numbers for those patients treated in primary care.
An accurate blood test for AD was developed to streamline the diagnostic process. This was used for testing of 1213 patients in Sweden who were already undergoing clinical evaluation due to cognitive symptoms between February 2020 and January 2024.
The results of the blood test called “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.
According to the study, the APS2 and percentage of p-tau217 (plasma phosphorylated tau 217) alone had high diagnostic accuracy for identifying AD among individuals with cognitive symptoms in primary and secondary care using predefined cutoff values.
The study concludes that future studies should evaluate how the use of blood tests for these biomarkers influences clinical care.
The above detailed Swedish research paper is to be found at this link – https://jamanetwork.com/journals/jama/fullarticle/2821669
The University of Eastern Finland’s Brain Research Unit is now validating the blood biomarker pTau217, which is associated with pathological changes in Alzheimer’s disease, for clinical use. The goal is to launch diagnostics in early 2025. The diagnostic accuracy of this biomarker has been shown to be on par with the expensive amyloid PET scan and is even more accurate than traditional cerebrospinal fluid. It should be noted that the blood pTau217 test is not recommended for testing asymptomatic individuals and cannot be used as the sole diagnostic criterion for Alzheimer’s disease.
More information can be found at their website – https://sites.uef.fi/aivobiomarkkeritutkimukset/?lang=en
