Utility of the Spanish version of the FTLD-modified CDR in the diagnosis and staging in frontotemporal lobar degeneration

• We assess patients with bvFTD, PPA and AD with our version of the FTLD-CDR.
• The scale is useful to characterize the non-amnestic symptoms of dementia.
• A significant reduction of the diagnostic error rate was found.
• It helps particularly in mild impairments due to behavioral or language symptoms.
• Characterizing and tracking the course of patients with FTLD is needed.

IntroductionThe Clinical Dementia Rating Scale (CDR) is a tool designed to quantify the severity of dementia symptoms and is also useful to assess disease progression, in Alzheimer's disease (AD). A new version of the scale was developed by adding two extra domains that focused on the core aspects of frontotemporal dementia symptomatology, Language and Behavior/Comportment/Personality.ObjectivesIn this study, we adapted and validated the modified CDR scale in our setting and language (Rioplatense-Spanish).Materials and methods46 patients with probable AD, 27 behavioral variant of Frontotemporal Dementia (bvFTD), 18 Primary Progressive Aphasia (PPA) and 40 healthy participants were included. The adapted version of the scale was administered by a blind rater who interviewed patients together with patient's caregiver.ResultsUsing ROC curves, the domain language and behavior were superior to the memory domain in accuracy for detecting PPA and bvFTD, respectively, but both of them had equivalent diagnostic accuracies for probable AD. Logistic regression analyses showed that either the LANG or BEHAV domains significantly improved the discrimination between probable AD, bvFTD and PPA.ConclusionsThe Spanish version of the modified CDR adds value for the characterization of the non-amnestic symptoms in patients with neurodegenerative dementias.