BACKGROUND: Behavioural variant of frontotemporal dementia (bvFTD) frequently presents complex behavioural changes, that rarely occur in isolation. Targeting behavioural phenotypes instead of single behavioural symptoms may potentially provide a disease model in which to investigate brain substrates of behavioural abnormalities. OBJECTIVE: To identify behavioural phenotypes and to assess the associated brain correlates in a cohort of patients with bvFTD. METHODS: Two hundred and seven consecutive individuals fulfilling clinical criteria for bvFTD were enrolled. Each participant's caregiver completed frontal behavioural inventory on 24 key behavioural disturbances. Confirmatory factor analysis (CFA) models were applied, and behavioural phenotypes identified. For each phenotype, a score was derived based on the "best" CFA model (Bifactor CFA). One hundred two participants underwent SPECT scan. A regression analysis between scores for each factor and regional cerebral blood flow was carried out (P<0.001). RESULTS: One "general" behavioural phenotype and four factors were identified, that were termed "disinhibited", "apathetic", "aggressive", and "language" phenotypes. The most robust brain correlate was identified for "disinhibited" phenotype, in the region of the anterior cingulated and anterior temporal cortex, bilaterally, and for apathetic phenotype in the left dorsolateral frontal cortex. As expected, language phenotype correlated with greater hypoperfusion in the left frontotemporal lobes. No significant correlation between aggressive phenotype and regional cerebral blood flow was found. Moreover, the "general" behavioural severity was associated with greater damage in the right frontal lobe. CONCLUSIONS: Behavioural phenotypes are associated with specific brain damage in bvFTD, involving distinct cerebral networks.
BACKGROUND: Behavioural variant of frontotemporal dementia (bvFTD) frequently presents complex behavioural changes, that rarely occur in isolation. Targeting behavioural phenotypes instead of single behavioural symptoms may potentially provide a disease model in which to investigate brain substrates of behavioural abnormalities. OBJECTIVE: To identify behavioural phenotypes and to assess the associated brain correlates in a cohort of patients with bvFTD. METHODS: Two hundred and seven consecutive individuals fulfilling clinical criteria for bvFTD were enrolled. Each participant's caregiver completed frontal behavioural inventory on 24 key behavioural disturbances. Confirmatory factor analysis (CFA) models were applied, and behavioural phenotypes identified. For each phenotype, a score was derived based on the "best" CFA model (Bifactor CFA). One hundred two participants underwent SPECT scan. A regression analysis between scores for each factor and regional cerebral blood flow was carried out (P<0.001). RESULTS: One "general" behavioural phenotype and four factors were identified, that were termed "disinhibited", "apathetic", "aggressive", and "language" phenotypes. The most robust brain correlate was identified for "disinhibited" phenotype, in the region of the anterior cingulated and anterior temporal cortex, bilaterally, and for apathetic phenotype in the left dorsolateral frontal cortex. As expected, language phenotype correlated with greater hypoperfusion in the left frontotemporal lobes. No significant correlation between aggressive phenotype and regional cerebral blood flow was found. Moreover, the "general" behavioural severity was associated with greater damage in the right frontal lobe. CONCLUSIONS: Behavioural phenotypes are associated with specific brain damage in bvFTD, involving distinct cerebral networks.
Authors: Sander C J Verfaillie; Sofie M Adriaanse; Maja A A Binnewijzend; Marije R Benedictus; Rik Ossenkoppele; Mike P Wattjes; Yolande A L Pijnenburg; Wiesje M van der Flier; Adriaan A Lammertsma; Joost P A Kuijer; Ronald Boellaard; Philip Scheltens; Bart N M van Berckel; Frederik Barkhof Journal: Eur Radiol Date: 2015-04-22 Impact factor: 5.315
Authors: Chris J D Hardy; Aisling H Buckley; Laura E Downey; Manja Lehmann; Vitor C Zimmerer; Rosemary A Varley; Sebastian J Crutch; Jonathan D Rohrer; Elizabeth K Warrington; Jason D Warren Journal: J Alzheimers Dis Date: 2016 Impact factor: 4.472
Authors: Alexander Frizell Santillo; Karl Lundblad; Markus Nilsson; Maria Landqvist Waldö; Danielle van Westen; Jimmy Lätt; Erik Blennow Nordström; Susanna Vestberg; Olof Lindberg; Christer Nilsson Journal: PLoS One Date: 2016-10-10 Impact factor: 3.240
Authors: Claire M O'Connor; Lindy Clemson; Michael Hornberger; Cristian E Leyton; John R Hodges; Olivier Piguet; Eneida Mioshi Journal: Neurol Clin Pract Date: 2016-10