title: Sleep disturbances in patients with mild-stage Alzheimer's disease.
abstract: We examined the ability of sleep/wake measures to discriminate 45 control subjects from 44 mild Alzheimer's disease (AD) patients. Sleep fragmentation was observed as indicated by significant increases in time awake (37-52%) and number of awakenings (31-36%) during the night as compared to controls. Further, slow wave sleep (SWS) was significantly reduced (22%) in AD patients relative to controls. These findings are consistent with our earlier observations of increased wakefulness and decreased SWS in mild-moderate, moderate-severe, and severe stage AD patients. However, when we used these sleep/wake stage measures in discriminant analyses to classify the current AD subjects vs control subjects, the analyses failed to confirm our earlier high classification rate (90%). The present groups were discriminated at overall classification rates of only 63-67%. We conclude that while sleep/wake patterns are significantly disturbed in AD, this phenomenon is not diagnostically useful for discrimination of mild stage AD.
authors.affiliation: Department of Psychiatry and Behavioral Sciences, University of Washington.
authors.forename: M V
authors.initials: MV
authors.lastname: Vitiello
authors.forename: P N
authors.initials: PN
authors.lastname: Prinz
authors.forename: D E
authors.initials: DE
authors.lastname: Williams
authors.forename: M S
authors.initials: MS
authors.lastname: Frommlet
authors.forename: R K
authors.initials: RK
authors.lastname: Ries
mesh_terms: D000368:Aged; D000544:Alzheimer Disease / Q000150:complications*; D005260:Female; D006801:Humans; D008297:Male; D011569:Psychiatric Status Rating Scales; D012894:Sleep Stages; D012893:Sleep Wake Disorders / Q000209:etiology*