title: Gait and subcortical hyperintensities in mild Alzheimer's disease and aging.
abstract: OBJECTIVE
  The relationship between subcortical hyperintensities (SH) on brain MRI and gait parameters in aging and Alzheimer's disease (AD) is unclear. This study compared gait in 42 mild AD patients to 22 normal controls (NC) based on their SH severity and correlated them to SH burden in these groups.
  
  
  METHODS
  Gait velocity, stride length, cadence and step width were captured on an automated walkway. Severity of SH on MRI was visually scored, which was used to dichotomize the AD and NC groups into high and low SH severity subgroups. Correlations between gait parameters and total and regional distribution of SH were explored.
  
  
  RESULTS
  Compared to both AD subgroups and the NC subgroup with high SH severity, the NC subgroup with low SH severity had a significantly faster velocity (127 cm/s). Overall SH severity correlated significantly with stride length and velocity in the AD (r = -0.4, p = 0.01) and NC (r = -0.4, p = 0.02) groups, respectively, specifically with SH severity in the frontal and basal ganglion regions.
  
  
  CONCLUSIONS
  SH burden may have a relatively stronger association with slower gait velocity in NC than in patients with mild AD. The fronto-subcortical SH load may influence gait in AD and aging.
authors.affiliation: L C Campbell Cognitive Neurology Research Unit, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada. neelesh.nadkarni@utoronto.ca
authors.forename: Neelesh K
authors.initials: NK
authors.lastname: Nadkarni
authors.forename: William E
authors.initials: WE
authors.lastname: McIlroy
authors.forename: Elysha
authors.initials: E
authors.lastname: Mawji
authors.forename: Sandra E
authors.initials: SE
authors.lastname: Black
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000473:pathology* / Q000502:physiology*; D000544:Alzheimer Disease / Q000473:pathology* / Q000503:physiopathology*; D001479:Basal Ganglia / Q000473:pathology / Q000502:physiology; D001921:Brain / Q000473:pathology*; D005260:Female; D005625:Frontal Lobe / Q000473:pathology / Q000502:physiology; D005684:Gait / Q000502:physiology*; D006801:Humans; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D011569:Psychiatric Status Rating Scales