Alpha‐synuclein co‐pathology in Alzheimer’s disease identified by RT‐QUIC identification

Abstract

AbstractBackgroundalpha‐synuclein co‐pathology may influence Alzheimer’s disease (AD) phenotype but its presence has never been tested in large series of patients. Real‐time quaking‐induced conversion (RT‐QuIC) recently provided evidence of alpha‐synuclein seeding activity in CSF and olfactory mucosa of patients with alpha‐synucleinopathiesMethoda preliminary set of 82 AD patients (mean age 70,3 + 7.3 years) underwent CSF analyses for Tau, P‐tau and A‐beta amyloid and an extensive cognitive, behavioral and motor assessment. RT‐QuiC for alpha‐synuclein was performed on CSF samples.Resultalpha synuclein RT‐QuIC resulted positive in thirty‐nine out of 82 AD patients (47.6%). AD patients with positive alpha‐synuclein were comparable for age and disease severity those negative to RT‐QuIC assay including Tau/P‐Tau and A‐beta CSF markers in cross‐sectional analyses but exhibited higher prevalence of parkinsonism (p=0.02).Conclusionthese preliminary findings indicate that alpha‐synuclein co‐pathology might be detected in more than one third of Alzheimer’s disease patients. These findings might potentially explain the clinical variability of AD including age at onset, progression and response to treatment observed in clinical series. Larger longitudinal studies are warranted to confirm and extend these findings.