title: Dual-tasking gait variability and cognition in late-life depression.
abstract: OBJECTIVE
  Studies have demonstrated an association between major depressive disorder (MDD) symptoms and fall risk in older adults, which may be at least partially mediated by executive functioning skills. There have also been observations of increased gait variability associated with fall risk and disease. This preliminary study first sought to understand whether gait variability in the context of dual task cost differs among older adults with MDD, relative to those with no history of psychiatric illness, and second, to identify relationships between gait variability measures and cognitive functioning in the context of MDD.
  
  
  METHODS
  We recruited 15 older adults with MDD and 17 non-depressed (ND) community-dwelling older adults. All participants had impaired balance based on unipedal stance time. Assessments included neuropsychological measures and measures of gait variability using an instrumented gait mat (GAITRite© ) in the context of dual task relative to single task performance (i.e., dual task cost).
  
  
  RESULTS
  The groups did not differ on any gait variability parameters. The MDD group demonstrated poorer performance in the psychomotor speed domain, relative to the ND group, but cognitive functioning between the groups in other domains was equivalent. In MDD, increased variability in stride time, stride velocity, and swing time during dual-tasking were associated with poorer executive functioning and visual memory. In ND, no significant relationships between gait variables and cognitive performance were observed.
  
  
  CONCLUSIONS
  Findings suggest that unique cognitive mechanisms underlie mobility problems associated with fall risk in late-life depression.
authors.affiliation: University of Michigan, Ann Arbor, MI, USA.
authors.forename: Nicolette M
authors.initials: NM
authors.lastname: Gabel
authors.affiliation: University of Illinois at Chicago, Chicago, IL, USA.
authors.forename: Natania A
authors.initials: NA
authors.lastname: Crane
authors.affiliation: University of Michigan, Ann Arbor, MI, USA.
authors.forename: Erich T
authors.initials: ET
authors.lastname: Avery
authors.affiliation: University of Michigan, Ann Arbor, MI, USA.
authors.forename: Rachel E
authors.initials: RE
authors.lastname: Kay
authors.affiliation: University of Michigan, Ann Arbor, MI, USA.
authors.forename: Amanda
authors.initials: A
authors.lastname: Laurent
authors.affiliation: University of Michigan, Ann Arbor, MI, USA.
authors.forename: Bruno
authors.initials: B
authors.lastname: Giordani
authors.affiliation: University of Michigan, Ann Arbor, MI, USA.|VA Ann Arbor Healthcare System, Ann Arbor, MI, USA.
authors.forename: Neil B
authors.initials: NB
authors.lastname: Alexander
authors.affiliation: University of Michigan, Ann Arbor, MI, USA.|University of Illinois at Chicago, Chicago, IL, USA.|Jesse Brown VA Medical Center, Chicago, IL, USA.
authors.forename: Sara L
authors.initials: SL
authors.lastname: Weisenbach
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001288:Attention / Q000502:physiology; D016022:Case-Control Studies; D003071:Cognition / Q000502:physiology*; D003865:Major Depressive Disorder / Q000503:physiopathology* / Q000523:psychology; D005260:Female; D005684:Gait / Q000502:physiology*; D015577:Geriatric Assessment; D006801:Humans; D008297:Male; D008568:Memory / Q000502:physiology; D008875:Middle Aged; D009483:Neuropsychological Tests; D011597:Psychomotor Performance / Q000502:physiology; D016138:Walking
keywords: balance; executive functioning; fall; gait; late-life depression; mobility