title: NREM sleep transient events in fronto-temporal dementia: beyond sleep stage architecture.
abstract: Frontotemporal dementia (FTD) is increasingly becoming recognized as a major cause of early onset (<65 years) neurodegenerative dementia. Although sleep disorders significantly impair patients' and caregivers' quality of life in neurodegenerative diseases, polysomnographic data in FTD patients are scarce in literature. Aim of our study was to investigate sleep microstructure in FTD, by means of Cyclic Alternating Pattern (CAP), in a group of ten behavioral variant FTD patients (6 M, 4 F; mean age 61.2±7.3 years; disease duration: 1.4±0.7 years) and to compare them with cognitively intact healthy elderly. Sleep in FTD patients was altered at different levels, involving not only the conventional sleep stage architecture parameters (total sleep time, single stage percentage, NREM/REM cycle organization), but also microstructure. FTD subjects showed CAP disruption with decreased slow wave activity related phases (A1 index, n/h:14.5±6.8 vs 38.8±6.6; p<.001) and increased arousal-related fast CAP components (A2 index 22.9±8.2 vs 11.6±3.7; p=.006; A3 index 41.9±20.7 vs 13.0±6.5; p=.002). Several correlations between sleep variables and neuropsychological tests were found. Sleep impairment in FTD may be specifically related to the specific frontal lobe involvement in the neurodegenerative process. The pattern of alterations seems somewhat peculiar, probably due to the anatomical distribution of the neurodegenerative process with a major impact on frontal lobe generated sleep transients, and a substantial sparing of phenomena related to the posterior cortex.
authors.affiliation: Neurology Unit, Department of Clinical and Experimental Medicine, University of Pisa, Via Roma 67, Pisa, Italy. Email: michelangelo.mvg@tin.it.
authors.forename: Michelangelo
authors.initials: M
authors.lastname: Maestri
authors.forename: Luca
authors.initials: L
authors.lastname: Carnicelli
authors.forename: Nicholas-Tiberio
authors.initials: NT
authors.lastname: Economou
authors.forename: Anastasios
authors.initials: A
authors.lastname: Bonakis
authors.forename: Thomas
authors.initials: T
authors.lastname: Paparrigopoulos
authors.forename: Sokratis T
authors.initials: ST
authors.lastname: Papageorgiou
authors.forename: Filippo Sean
authors.initials: FS
authors.lastname: Giorgi
authors.forename: Elisa
authors.initials: E
authors.lastname: Di Coscio
authors.forename: Gloria
authors.initials: G
authors.lastname: Tognoni
authors.forename: Raffaele
authors.initials: R
authors.lastname: Ferri
authors.forename: Ubaldo
authors.initials: U
authors.lastname: Bonuccelli
authors.forename: Enrica
authors.initials: E
authors.lastname: Bonanni
mesh_terms: D000368:Aged; D058256:Brain Waves; D005260:Female; D057180:Frontotemporal Dementia / Q000175:diagnosis / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012895:Sleep, REM