title: Sleep disturbance in dementia with Lewy bodies and Alzheimer's disease: a multicenter analysis.
abstract: OBJECTIVE
  Evidence suggests that patients with dementia with Lewy bodies (DLB) may have more nocturnal sleep disturbance than patients with Alzheimer's disease (AD). We sought to confirm such observations using a large, prospectively collected, standardized, multicenter-derived database, i.e. the National Alzheimer's Coordinating Center Uniform Data Set.
  
  
  METHODS
  Nocturnal sleep disturbance (NSD) data, as characterized by the Neuropsychiatric Inventory Questionnaire (NPI-Q), were derived from 4,531 patients collected between September 2005 and November 2008 from 32 National Institute on Aging participating AD centers. Patient and informant characteristics were compared between those with and without NSD by dementia diagnosis (DLB and probable AD). Finally, a logistic regression model was created to quantify the association between NSD status and diagnosis while adjusting for these patient/informant characteristics, as well as center.
  
  
  RESULTS
  NSD was more frequent in clinically diagnosed DLB relative to clinically diagnosed AD (odds ratio = 2.93, 95% confidence interval = 2.22-3.86). These results were independent from the gender of the patient or informant, whether the informant lived with the patient, and other patient characteristics, such as dementia severity, depressive symptoms, and NPI-Q-derived measures of hallucinations, delusions, agitation and apathy. In AD, but not DLB, patients, NSD was associated with more advanced disease. Comorbidity of NSD with hallucinations, agitation and apathy was higher in DLB than in AD. There was also evidence that the percentage of DLB cases with NSD showed wide variation across centers.
  
  
  CONCLUSIONS
  As defined by the NPI-Q, endorsement of the nocturnal behavior item by informants is more likely in patients with DLB when compared to AD, even after the adjustment of key patient/informant characteristics.
authors.affiliation: Department of Neurology, Emory University School of Medicine, Wesley Woods Health Center, 1841 Clifton Road, Atlanta, GA 30329, USA. dbliwis@emory.edu
authors.forename: Donald L
authors.initials: DL
authors.lastname: Bliwise
authors.forename: Nathaniel D
authors.initials: ND
authors.lastname: Mercaldo
authors.forename: Alon Y
authors.initials: AY
authors.lastname: Avidan
authors.forename: Bradley F
authors.initials: BF
authors.lastname: Boeve
authors.forename: Sophia A
authors.initials: SA
authors.lastname: Greer
authors.forename: Walter A
authors.initials: WA
authors.lastname: Kukull
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000453:epidemiology*; D015897:Comorbidity; D016208:Databases, Factual; D005260:Female; D006801:Humans; D020961:Lewy Body Disease / Q000453:epidemiology*; D016015:Logistic Models; D008297:Male; D009483:Neuropsychological Tests; D011446:Prospective Studies; D012893:Sleep Wake Disorders / Q000453:epidemiology*