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Published on: October 13, 2016
Apraxia screening predicts Alzheimer pathology in frontotemporal dementia
Matthias Pawlowski1, Viktoria Joksch2, Heinz Wiendl2
1Department of Neurology, University Hospital Münster, Münster, Germany matthias.pawlowski@ukmuenster.de andreas.johnen@ukmuenster.de.
Objectives:
Frontotemporal dementia (FTD) is a heterogeneous clinical syndrome linked to diverse types of underlying neuropathology. Diagnosis is mainly based on clinical presentation and accurate prediction of underlying neuropathology remains difficult.
Methods:
We present a large cohort of patients with FTD spectrum diseases (n=84). All patients were thoroughly characterised by cerebrospinal fluid (CSF) Alzheimer's disease (AD) biomarkers, neuroimaging, neuropsychological testing and standardised apraxia screening.
Results:
A potential AD pathology was found in 43% of patients with FTD. CSF AD biomarker levels positively correlated with AD-typical apraxia scores in patients with FTD. The discriminative power of apraxia test results indicative of AD pathology was high (sensitivity: 90%, specificity: 66%).
Conclusions:
Apraxia is common in neurodegenerative dementias but under-represented in clinical workup and diagnostic criteria. Standardised apraxia screening may serve as bedside test to objectify an AD-typical apraxia profile as an early and robust sign of AD pathology in patients with FTD.
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