Plasma Phospho-Tau Identifies Alzheimer's Co-Pathology in Patients with Lewy Body Disease

Background: Alzheimer's disease co-pathology is common in dementia with Lewy bodies and Parkinson's disease with dementia (Lewy body disease) and can reliably be detected with positron emission tomography (PET) or cerebrospinal fluid (CSF) biomarkers. Recently developed blood biomarkers are more accessible and less expensive alternatives. Objective: To investigate if plasma phospho-tau217 and phospho-tau181 can detect Alzheimer's pathology in Lewy body disease with dementia. Methods: In this cross-sectional study we investigated plasma phospho-tau217 and phospho-tau181 in 35 patients with Lewy body disease with dementia. Patients underwent tau-PET imaging (F-18-RO948). Results: Plasma phospho-tau217 correlated with plasma phospho-tau181, CSF phospho-tau217 (r(s) = 0.68, P < 0.001), and negatively with CSF beta-amyloid(42/40) (r(s) = -0.52, P = 0.001). Plasma phospho-tau217 and phospho-tau181 correlated with tau-PET signal in the temporal cortex (r(s) > 0.56, P < 0.001) and predicted abnormal tau-PET status and beta-amyloid status (area under the curve > 0.78 and > 0.81, respectively). Conclusion: Plasma phospho-tau might be a useful marker for Alzheimer's co-pathology in Lewy body disease with dementia. (c) 2020 The Authors. Movement Disorders published by Wiley Periodicals LLC. on behalf of International Parkinson and Movement Disorder Society.

Automated summary

This study investigated plasma phospho-tau217 and phospho-tau181 in 35 patients with Lewy body disease with dementia, finding correlations with CSF and tau-PET imaging, and predictive value for pathological status. Plasma phospho-tau may serve as a useful marker for Alzheimer's co-pathology in Lewy body disease with dementia.