White matter hyperintensities and dynamics of postural control

Background: White matter hyperintensities (WMHs) on MRI have been associated with age, cardiovascular risk factors and falls in the elderly. This study evaluated the relationship between WMHs and dynamics of postural control in older adults without history of falls. Methods: We studied 76 community-living subjects without history of falls (age 64.5 +/- 7.3 years). Brain and WMH volume calculations and clinical rating were done on fluid-attenuation inversion recovery (FLAIR) and MP-RAGE MR images on 3 T. Balance was assessed from the center of pressure displacement using the force platform during 3 min of quiet standing using traditional and dynamic measures (using stabilogram-diffusion analysis). Gait speed was measured from 12-min walk. Results: Age-adjusted periventricular and focal WMHs were associated with changes in certain dynamic balance measures, including reduced range of postural sway in anteroposterior direction (fronto-temporal WMHs, P = .045; parieto-occipital WMHs, P = .009) and more irregular long-term mediolateral fluctuations (P = .046). Normal walking speed was not affected by WMHs. Conclusions: Periventricular and focal WMHs affect long-term dynamics of postural control, which requires engagement of feedback mechanisms, and may contribute to mobility decline in the elderly. (C) 2009 Elsevier Inc. All rights reserved.