title: The impact of anxiety on conversion from mild cognitive impairment to Alzheimer's disease.
abstract: OBJECTIVE
  To compare state and trait anxiety in mild cognitive impairment (MCI) patients and matched control subjects, and to assess the impact of these variables in predicting conversion to Alzheimer's disease.
  
  
  METHODS
  One hundred and forty-eight patients with MCI, broadly defined, were assessed and followed systematically. Baseline predictors for follow-up conversion to AD (entire sample: 39/148 converted to Alzheimer's disease (AD)) included the Spielberger State-Trait Anxiety Inventory (STAI).
  
  
  RESULTS
  At baseline evaluation, MCI patients had higher levels of state and trait anxiety than controls, with no differences between future AD converters (n = 39) and non-converters. In age-stratified Cox proportional hazards model analyses, STAI State was not a significant predictor of conversion to AD (STAI State < or =30 vs. > 30 risk ratio, 1.68; 95% CI, 0.75, 3.77; p = 0.21), but higher Trait scores indicated a lower risk of conversion when STAI State, education, the Folstein Mini-Mental State Examination and HAM-D (depression score) were also included in the model (STAI Trait < or =30 vs. > 30 risk ratio, 0.36; 95% CI, 0.16, 0.82; p = 0.015).
  
  
  CONCLUSIONS
  In contrast to two other recent studies that showed anxiety predicted cognitive decline or conversion to AD, in this clinic-based sample, state anxiety was not a significant predictor. However, higher Trait anxiety predicted a lower risk of future conversion to AD. Further research with systematic long-term follow-up in larger samples is needed to clarify the role of state and trait anxiety in predicting MCI conversion to AD.
authors.affiliation: Louisiana State University Health Sciences Center, Department of Neurology, New Orleans, LA, USA. ddevie@lsuhsc.edu
authors.forename: Deidre J
authors.initials: DJ
authors.lastname: Devier
authors.forename: Gregory H
authors.initials: GH
authors.lastname: Pelton
authors.forename: Matthias H
authors.initials: MH
authors.lastname: Tabert
authors.forename: Xinhua
authors.initials: X
authors.lastname: Liu
authors.forename: Katrina
authors.initials: K
authors.lastname: Cuasay
authors.forename: Rachel
authors.initials: R
authors.lastname: Eisenstadt
authors.forename: Karen
authors.initials: K
authors.lastname: Marder
authors.forename: Yaakov
authors.initials: Y
authors.lastname: Stern
authors.forename: D P
authors.initials: DP
authors.lastname: Devanand