The association between white matter hyperintensity volume and gait performance under single and dual task conditions in older people with dementia: A cross-sectional study.

Abstract Background : Understanding the relationship between white matter hyperintensities (WMHs) and gait may assist in understanding the central control of gait and determining treatment modalities. These relationships are yet to be realized in older people with dementia. Objective : To examine the association between WMH volume and gait under single-task and dual task (DT) conditions in people with dementia. Methods : Twenty-eight community-dwelling older people with dementia (median age=83 years; [IQR=77–86]; 36% female) had timed gait speed assessed at usual pace. Gait (speed, stride length, cadence) was assessed using the GAITRite® mat under three conditions (n = 18/28): a) single-task, b) functional DT: carrying a glass of water and c) cognitive DT: counting backwards from 30. WMH volumes were quantified using a fully automated segmentation toolbox. Results : Total, temporal and parietal WMH volumes were negatively correlated with timed and functional DT gait speed, and with stride length under single-task, functional DT and cognitive DT conditions. Frontal WMH volumes were negatively correlated with timed gait speed and stride length under single-task and functional DT conditions. Participants with higher total WMH burden had significantly slower timed and functional DT gait speed and reduced stride length under single-task, functional DT and cognitive DT conditions compared to participants with lower WMH burden. Conclusions : WMH volume was associated with slower gait speed and reduced stride length, but not cadence, under single-task and DT conditions in people with dementia. Further research is needed to confirm these findings and determine whether vascular risk management can improve gait in older people with dementia.