Mario F Mendez1,2, Diana Chavez1, Randy E Desarzant1, Oleg Yerstein1. 1. Departments of Neurology and Psychiatry & Behavioral Sciences, David Geffen School of Medicine, University of California-Los Angeles, Los Angeles, California. 2. Neurology Service, Neurobehavior Unit, Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, California.
Abstract
BACKGROUND: Semantic dementia (SD) is characterized by progressive semantic anomia extending to a multimodal loss of semantic knowledge. Although often considered an early-onset dementia, SD also occurs in later life, when it may be misdiagnosed as Alzheimer disease (AD). OBJECTIVE: To evaluate late-onset SD in comparison to early-onset SD and to AD. METHODS: We identified 74 individuals with SD and then compared those with late-onset SD (≥65 years of age) to those with early-onset SD (<65) on demographic and clinical features. We also compared a subgroup of 23 of the late-onset SD individuals with an equal number of individuals with clinically probable AD. RESULTS: Twenty-six (35.1%) of the SD individuals were late onset, and 48 (64.9%) were early onset. There were no differences between the two groups on clinical measures, although greater asymmetry of temporal involvement trended to significance in the late-onset SD group. Compared to the 23 AD individuals, the subgroup of 23 late-onset SD individuals had worse performance on confrontational naming, irregular word reading, and face recognition; however, this subgroup displayed better verbal delayed recall and constructions. The late-onset SD individuals also experienced early personality changes at a time when most individuals with AD had not yet developed behavioral changes. CONCLUSIONS: Approximately one-third of SD individuals may be late onset, and the differentiation of late-onset SD from AD can lead to better disease management, education, and prognosis. SD may be distinguished by screening for disproportionate changes in reading, face recognition, and personality.
BACKGROUND:Semantic dementia (SD) is characterized by progressive semantic anomia extending to a multimodal loss of semantic knowledge. Although often considered an early-onset dementia, SD also occurs in later life, when it may be misdiagnosed as Alzheimer disease (AD). OBJECTIVE: To evaluate late-onset SD in comparison to early-onset SD and to AD. METHODS: We identified 74 individuals with SD and then compared those with late-onset SD (≥65 years of age) to those with early-onset SD (<65) on demographic and clinical features. We also compared a subgroup of 23 of the late-onset SD individuals with an equal number of individuals with clinically probable AD. RESULTS: Twenty-six (35.1%) of the SD individuals were late onset, and 48 (64.9%) were early onset. There were no differences between the two groups on clinical measures, although greater asymmetry of temporal involvement trended to significance in the late-onset SD group. Compared to the 23 AD individuals, the subgroup of 23 late-onset SD individuals had worse performance on confrontational naming, irregular word reading, and face recognition; however, this subgroup displayed better verbal delayed recall and constructions. The late-onset SD individuals also experienced early personality changes at a time when most individuals with AD had not yet developed behavioral changes. CONCLUSIONS: Approximately one-third of SD individuals may be late onset, and the differentiation of late-onset SD from AD can lead to better disease management, education, and prognosis. SD may be distinguished by screening for disproportionate changes in reading, face recognition, and personality.
Authors: David Bergeron; Maria L Gorno-Tempini; Gil D Rabinovici; Miguel A Santos-Santos; William Seeley; Bruce L Miller; Yolande Pijnenburg; M Antoinette Keulen; Colin Groot; Bart N M van Berckel; Wiesje M van der Flier; Philip Scheltens; Jonathan D Rohrer; Jason D Warren; Jonathan M Schott; Nick C Fox; Raquel Sanchez-Valle; Oriol Grau-Rivera; Ellen Gelpi; Harro Seelaar; Janne M Papma; John C van Swieten; John R Hodges; Cristian E Leyton; Olivier Piguet; Emily J Rogalski; Marsel M Mesulam; Lejla Koric; Kristensen Nora; Jeéreémie Pariente; Bradford Dickerson; Ian R Mackenzie; Ging-Yuek R Hsiung; Serge Belliard; David J Irwin; David A Wolk; Murray Grossman; Matthew Jones; Jennifer Harris; David Mann; Julie S Snowden; Patricio Chrem-Mendez; Ismael L Calandri; Alejandra A Amengual; Carole Miguet-Alfonsi; Eloi Magnin; Giuseppe Magnani; Roberto Santangelo; Vincent Deramecourt; Florence Pasquier; Niklas Mattsson; Christer Nilsson; Oskar Hansson; Julia Keith; Mario Masellis; Sandra E Black; Jordi A Matías-Guiu; María-Nieves Cabrera-Martin; Claire Paquet; Julien Dumurgier; Marc Teichmann; Marie Sarazin; Michel Bottlaender; Bruno Dubois; Christopher C Rowe; Victor L Villemagne; Rik Vandenberghe; Elias Granadillo; Edmond Teng; Mario Mendez; Philipp T Meyer; Lars Frings; Alberto Lleó; Rafael Blesa; Juan Fortea; Sang Won Seo; Janine Diehl-Schmid; Timo Grimmer; Kristian Steen Frederiksen; Pascual Sánchez-Juan; Gaël Chételat; Willemijn Jansen; Rémi W Bouchard; Robert Jr Laforce; Pieter Jelle Visser; Rik Ossenkoppele Journal: Ann Neurol Date: 2018-11 Impact factor: 10.422
Authors: Phillip D Fletcher; Laura E Downey; Hannah L Golden; Camilla N Clark; Catherine F Slattery; Ross W Paterson; Jonathan D Rohrer; Jonathan M Schott; Martin N Rossor; Jason D Warren Journal: Brain Date: 2015-10-12 Impact factor: 13.501