Portuguese version of the CDR plus NACC FTLD: Validation studies

Introduction: The CDR Dementia Staging Instrument PLUS National Alzheimer’s Coordinating Center (CDR plus NACC FTLD) was developed by adding to the standard CDR two extra domains focused on the main features of frontotemporal lobar degeneration (FTLD): language and behavior/personality. We intended to perform the validation studies for the European-Portuguese population. Methods: A total of 105 participants matched for age, education, and disease staging (35 bvFTD, 35 AD, and 35 controls) were included. A translated-version of the CDR and the two added domains was administered by a neuropsychologist who was blinded to the diagnosis. Results: The bvFTD group had higher baseline CDR plus NACC FTLD scores compared to the AD and controls. Only the sum-of-boxes (SB) score, the behavior/personality, and language domains were able to distinguish between clinical groups. Logistic regression analyses showed that adding the behavior/personality domain with or without language significantly enhanced the discriminating ability. Discussion: Results show that the CDR plus NACC FTLD is a reliable tool in the diagnostic process of bvFTD patients and has an added value in distinguishing them from patients with AD.