title: Patterns of focal gray matter atrophy are associated with bradykinesia and gait disturbances in older adults.
abstract: OBJECTIVE
  Identify the neuroimaging correlates of parkinsonian signs in older adults living in the community.
  
  
  METHODS
  Magnetic resonance imaging was obtained in 307 adults (82.9 years, 55% women, 39% blacks) concurrently with the Unified Parkinson Disease Rating scale-motor part. Magnetic resonance imaging measures included volume of whole-brain white matter hyperintensities and of gray matter for primary sensorimotor, supplementary motor, medial temporal areas, cerebellum, prefronto-parietal cortex, and basal ganglia.
  
  
  RESULTS
  About 25% of the participants had bradykinesia, 26% had gait disturbances, and 12% had tremor. Compared with those without, adults with any one of these signs were older, walked more slowly, had worse scores on tests of cognition, mood and processing speed, and higher white matter hyperintensities volume (all p ≤ .002). Gray matter volume of primary sensorimotor area was associated with bradykinesia (standardized odds ratio [95% confidence interval]: 0.46 [0.31, 0.68], p < .0001), and gray matter volume of medial temporal area was associated with gait disturbances (0.56 [0.42, 0.83], p < .0001), independent of white matter hyperintensities volume and age. Further adjustment for measures of muscle strength, cardiovascular health factors, cognition, processing speed, and mood or for gait speed did not substantially change these results.
  
  
  CONCLUSIONS
  Atrophy within primary sensorimotor and medial temporal areas might be important for development of bradykinesia and of gait disturbances in community-dwelling elderly adults. The pathways underlying these associations may not include changes in white matter hyperintensities volume, cognition, information processing speed, mood, or gait speed.
authors.affiliation: Department of Epidemiology, Graduate School of Public Health, 130 North Bellefield Street, Room 512, Pittsburgh, PA 15213, USA. rosanoc@edc.pitt.edu
authors.forename: Caterina
authors.initials: C
authors.lastname: Rosano
authors.forename: David A
authors.initials: DA
authors.lastname: Bennett
authors.forename: Anne B
authors.initials: AB
authors.lastname: Newman
authors.forename: Vijay
authors.initials: V
authors.lastname: Venkatraman
authors.forename: Kristine
authors.initials: K
authors.lastname: Yaffe
authors.forename: Tamara
authors.initials: T
authors.lastname: Harris
authors.forename: Stephen
authors.initials: S
authors.lastname: Kritchevsky
authors.forename: Howard J
authors.initials: HJ
authors.lastname: Aizenstein
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000473:pathology* / Q000502:physiology*; D001284:Atrophy / Q000473:pathology; D001921:Brain / Q000473:pathology* / Q000503:physiopathology; D015331:Cohort Studies; D005260:Female; D020233:Gait Disorders, Neurologic / Q000209:etiology* / Q000473:pathology / Q000503:physiopathology; D006801:Humans; D018476:Hypokinesia / Q000209:etiology* / Q000473:pathology / Q000503:physiopathology; D008279:Magnetic Resonance Imaging; D008297:Male; D020734:Parkinsonian Disorders / Q000209:etiology / Q000473:pathology / Q000503:physiopathology; D014202:Tremor / Q000209:etiology / Q000473:pathology / Q000503:physiopathology