title: Olfactory identification in amnestic and non-amnestic mild cognitive impairment and its neuropsychological correlates.
abstract: BACKGROUND
  Olfactory identification impairment in amnestic mild cognitive impairment (aMCI) patients is well documented and considered to be caused by underlying Alzheimer's disease (AD) pathology, contrasting with less clear evidence in non-amnestic MCI (naMCI). The aim was to (a) compare the degree of olfactory identification dysfunction in aMCI, naMCI, controls and mild AD dementia and (b) assess the relation between olfactory identification and cognitive performance in aMCI compared to naMCI.
  
  
  METHODS
  75 patients with aMCI and 32 with naMCI, 26 patients with mild AD and 27 controls underwent the multiple choice olfactory identification Motol Hospital Smell Test with 18 different odors together with a comprehensive neuropsychological examination.
  
  
  RESULTS
  Controlling for age and gender, patients with aMCI and naMCI did not differ significantly in olfactory identification and both performed significantly worse than controls (p<0.001), albeit also better than patients with mild AD (p<.001). In the aMCI group, higher scores on MMSE, verbal and non-verbal memory and visuospatial tests were significantly related to better olfactory identification ability. Conversely, no cognitive measure was significantly related to olfactory performance in naMCI.
  
  
  CONCLUSIONS
  Olfactory identification is similarly impaired in aMCI and naMCI. Olfactory impairment is proportional to cognitive impairment in aMCI but not in naMCI.
authors.affiliation: International Clinical Research Center, St. Anne's University Hospital Brno, Brno, Czech Republic; Memory Clinic, Department of Neurology, Charles University in Prague, 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic. Electronic address: martin.vyhnalek@fnmotol.cz.
authors.forename: Martin
authors.initials: M
authors.lastname: Vyhnalek
authors.affiliation: Memory Clinic, Department of Neurology, Charles University in Prague, 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic.
authors.forename: Hana
authors.initials: H
authors.lastname: Magerova
authors.affiliation: School of Aging Studies, University of South Florida, Tampa, FL, USA.
authors.forename: Ross
authors.initials: R
authors.lastname: Andel
authors.affiliation: International Clinical Research Center, St. Anne's University Hospital Brno, Brno, Czech Republic; Memory Clinic, Department of Neurology, Charles University in Prague, 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic.
authors.forename: Tomas
authors.initials: T
authors.lastname: Nikolai
authors.affiliation: International Clinical Research Center, St. Anne's University Hospital Brno, Brno, Czech Republic; Memory Clinic, Department of Neurology, Charles University in Prague, 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Kadlecova
authors.affiliation: International Clinical Research Center, St. Anne's University Hospital Brno, Brno, Czech Republic; Memory Clinic, Department of Neurology, Charles University in Prague, 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic.
authors.forename: Jan
authors.initials: J
authors.lastname: Laczo
authors.affiliation: International Clinical Research Center, St. Anne's University Hospital Brno, Brno, Czech Republic; Memory Clinic, Department of Neurology, Charles University in Prague, 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic.
authors.forename: Jakub
authors.initials: J
authors.lastname: Hort
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000175:diagnosis / Q000503:physiopathology / Q000523:psychology; D000647:Amnesia / Q000175:diagnosis* / Q000503:physiopathology / Q000523:psychology; D003071:Cognition; D060825:Cognitive Dysfunction / Q000175:diagnosis* / Q000503:physiopathology / Q000523:psychology; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D009812:Odorants; D000857:Olfaction Disorders / Q000175:diagnosis* / Q000503:physiopathology / Q000523:psychology; D012903:Smell
keywords: Alzheimer's disease; Cognition; Memory; Mild cognitive impairment; Olfaction disorders; Smell