Gait and subcortical hyperintensities in mild Alzheimer's disease and aging.

ABSTRACT

BACKGROUND/AIMS: 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. CONCLUSION: 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.