title: Vestibular Function Impairment in Alzheimer's Disease.
abstract: BACKGROUND
  Falls and fractures due to impaired balance in patients with Alzheimer's disease (AD) have an adverse effect on the clinical course of the disease.
  
  
  OBJECTIVE
  To evaluate balance impairment in AD from the viewpoint of vestibular functional impairment.
  
  
  METHODS
  The subjects were 12 patients with AD, 12 dementia-free elderly adults, and 12 younger adults. Vestibular function was assessed using a stepping test, caloric nystagmus, and a visual suppression (VS) test.
  
  
  RESULTS
  The stepping test was abnormal in 9 of the 12 patients in the AD group. An abnormal stepping test was not associated with self-reported dizziness or tendency to fall. Significant VS abnormalities were present in the AD group. The suppression rate of VS was lower in AD patients with either a tendency to fall or constructional apraxia than in AD patients without either. The velocity of the rapid phase of caloric nystagmus before the VS test was similar in the AD group and the elderly control group. Significant abnormalities of both caloric nystagmus and VS were not present in either the elderly or the younger control groups.
  
  
  CONCLUSIONS
  AD could involve impairments in the vestibular control of balance. The VS test is useful for assessing the tendency to fall in AD. Impairment of VS in AD might arise from cerebral vestibular cortex impairment rather than comorbid peripheral vestibular disorders.
authors.affiliation: Department of Neurology, Division of Clinical Medicine, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan.
authors.forename: Kiyotaka
authors.initials: K
authors.lastname: Nakamagoe
authors.affiliation: Department of Neurology, Division of Clinical Medicine, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan.
authors.forename: Suguru
authors.initials: S
authors.lastname: Fujimiya
authors.affiliation: Department of Physiology, Division of Biomedical Science, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan.
authors.forename: Tadachika
authors.initials: T
authors.lastname: Koganezawa
authors.affiliation: Department of Neurology, Division of Clinical Medicine, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan.
authors.forename: Kotarou
authors.initials: K
authors.lastname: Kadono
authors.affiliation: Department of Neurology, Division of Clinical Medicine, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan.
authors.forename: Kotone
authors.initials: K
authors.lastname: Shimizu
authors.affiliation: Department of Neurology, Division of Clinical Medicine, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan.
authors.forename: Natsu
authors.initials: N
authors.lastname: Fujizuka
authors.affiliation: Department of Neurology, Division of Clinical Medicine, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan.
authors.forename: Shino
authors.initials: S
authors.lastname: Takiguchi
authors.affiliation: Department of Neurology, Division of Clinical Medicine, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan.
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Ueno
authors.affiliation: Department of Neurology, Fuji Heavy Industries Health Insurance Society Ota Memorial Hospital, Gunma, Japan.
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Monzen
authors.affiliation: Department of Neurology, Division of Clinical Medicine, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Tamaoka
mesh_terms: D000161:Acoustic Stimulation; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000150:complications* / Q000000981:diagnostic imaging / Q000188:drug therapy; D014150:Antipsychotic Agents / Q000627:therapeutic use; D001921:Brain / Q000000981:diagnostic imaging / Q000473:pathology; D005260:Female; D006801:Humans; D020367:Iofetamine / Q000378:metabolism; D008297:Male; D009760:Nystagmus, Physiologic / Q000502:physiology; D004856:Postural Balance; D011569:Psychiatric Status Rating Scales; D018709:Statistics, Nonparametric; D015899:Tomography, Emission-Computed, Single-Photon; D015837:Vestibular Diseases / Q000175:diagnosis / Q000209:etiology*; D055815:Young Adult
chemical_list: D014150:Antipsychotic Agents; D020367:Iofetamine
keywords: Alzheimer’s disease; caloric tests; dementia; eye movements; hippocampus; inferior parietal lobule; vestibular function tests; vestibular imbalance; vestibular stimulation; visual suppression