title: Identification of VaD and AD prodromes: the Cache County Study.
abstract: BACKGROUND
  It is unclear whether vascular dementia (VaD) has a cognitive prodrome, akin to the mild cognitive impairment (MCI) prodrome to Alzheimer's dementia (AD). To evaluate whether VaD has a cognitive prodrome, and if it can be differentiated from prodromal AD, we examined neuropsychological test performance of participants in a nested case-control study within a population-based cohort aged 65 or older.
  
  
  METHODS
  Participants (n = 485) were identified from the Cache County Study, a large population-based study of aging and dementia. After an average of 3 years of follow-up, a total of 62 incident dementia cases were identified (14 VaD, 48 AD). We identified a number of neuropsychological tests (executive and memory) that discriminated between diagnosed VaD and AD cases. Multivariate analyses sought to differentiate between these same groups 3 years before clinical diagnosis.
  
  
  RESULTS
  The Consortium to Establish a Registry for Alzheimer's Disease Word List Recognition Test correct recognition of foils (mean difference, 1.25; 95% confidence interval [CI], 0.42 to 2.07; p < 0.01), Logical Memory I (mean difference, 7.16; 95% CI, 0.78 to 13.55, p < 0.05), Logical Memory II delayed recall (mean difference, 8.67; 95% CI, 1.59 to 15.74, p < 0.05), and percent savings (mean difference, 51.07; 95% CI, 32.58 to 69.56, p < 0.0001) differentiated VaD from AD cases after adjustment for age, sex, education, and dementia severity. Three years before dementia diagnosis, word list recognition ("no" responses mean difference, 1.40; 95% CI, 0.64 to 2.17; p < 0.001, and "yes" responses mean difference, -1.14; 95% CI, -2.14 to -0.13; p < 0.03) discriminated between prodromal VaD and AD.
  
  
  CONCLUSIONS
  These results suggest that VaD has a prodromal syndrome, the cognitive features of which are distinguishable from the cognitive prodrome of AD.
authors: Center for the Study of Aging and Human Development, Duke University Medical Center, Durham, NC, USA.
authors: K M
authors: KM
authors: Hayden
authors: L H
authors: LH
authors: Warren
authors: C F
authors: CF
authors: Pieper
authors: T
authors: T
authors: Østbye
authors: J T
authors: JT
authors: Tschanz
authors: M C
authors: MC
authors: Norton
authors: J C S
authors: JC
authors: Breitner
authors: K A
authors: KA
authors: Welsh-Bohmer