title: Cognitive impairment and preferences for current health.
abstract: BACKGROUND
  We assessed preferences for current health using the visual analogue scale (VAS), standard gamble (SG), time trade-off (TTO), and willingness to pay (WTP) in patients with cerebral aneurysms, a population vulnerable to cognitive deficits related to aneurysm bleeding or treatment.
  
  
  METHODS
  We measured VAS, SG, TTO, and WTP values for current health in 165 outpatients with cerebral aneurysms. We assessed cognitive impairment with the Mini Mental State Examination (MMSE; scores < 24 = cognitive impairment). We examined the distributions of preference responses stratified by cognitive status, and the relationship between preferences and cognitive impairment, patient characteristics, and aneurysm history.
  
  
  RESULTS
  Eleven patients (7%) had MMSE scores < 24. The distribution of preferences responses from patients with cognitive impairment had greater variance (SG, 0.39 vs. 0.21, P = 0.001; TTO, 0.36 vs. 0.24, P = 0.017) and altered morphology (VAS, P = 0.012; SG, P = 0.023) compared to the responses of unimpaired patients. There was good correlation between most preference measures for unimpaired patients (VAS:TTO, rho = 0.19, P = 0.018; SG:TTO, rho = 0.36, P < 0.001; SG:WTP, rho = -0.33, P < 0.001) and a trend towards significance with another pairing (VAS:WTP, rho = 0.16, P = 0.054). In subjects with cognitive impairment, there was a significant correlation only between VAS and TTO scores (rho = 0.76, P = 0.023). Separate regression models showed that cognitive impairment was associated with lower preferences on the VAS (beta = -0.12, P = 0.048), SG (beta = -0.23, P = 0.002), and TTO (beta = -0.17, P = 0.035).
  
  
  CONCLUSIONS
  Cognitive impairment is associated with lower preferences for current health in patients with cerebral aneurysms. Cognitively impaired patients have poor inter-preference test correlations and different response distributions compared to unimpaired patients.
authors.affiliation: Section of Neurosurgery, VA Connecticut Healthcare System, West Haven, Connecticut, USA. joseph.kingjr@va.gov
authors.forename: Joseph T
authors.initials: JT
authors.lastname: King
authors.forename: Joel
authors.initials: J
authors.lastname: Tsevat
authors.forename: Mark S
authors.initials: MS
authors.lastname: Roberts
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001294:Attitude to Health; D003072:Cognition Disorders / Q000523:psychology*; D003362:Cost-Benefit Analysis; D005260:Female; D006304:Health Status; D006801:Humans; D002532:Intracranial Aneurysm / Q000523:psychology*; D008297:Male; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales; D011788:Quality of Life