Gait phenotype from mild cognitive impairment to moderate dementia: results from the GOOD initiative.

BACKGROUND AND PURPOSE: The differences in gait abnormalities from the earliest to the later stages of dementia and in the different subtypes of dementia have not been fully examined. This study aims to compare spatiotemporal gait parameters in cognitively healthy individuals, patients with amnestic mild cognitive impairment (MCI) and non-amnestic MCI, and patients with mild and moderate stages of Alzheimer's disease (AD) and non-Alzheimer's disease (non-AD). METHODS: Based on a cross-sectional design, 1719 participants (77.4 ± 7.3 years, 53.9% female) were recruited from cohorts from seven countries participating in the Gait, Cognition and Decline (GOOD) initiative. Mean values and coefficients of variation of spatiotemporal gait parameters were measured during normal pace walking with the GAITRite system at all sites. RESULTS: Performance of spatiotemporal gait parameters declined in parallel with the stage of cognitive decline from MCI status to moderate dementia. Gait parameters of patients with non-amnestic MCI were more disturbed compared to patients with amnestic MCI, and MCI subgroups performed better than demented patients. Patients with non-AD dementia had worse gait performance than those with AD dementia. This degradation of gait parameters was similar between mean values and coefficients of variation of spatiotemporal gait parameters in the earliest stages of cognitive decline, but different in the most advanced stages, especially in the non-AD subtypes. CONCLUSIONS: Spatiotemporal gait parameters were more disturbed in the advanced stages of dementia, and more affected in the non-AD dementias than in AD. These findings suggest that quantitative gait parameters could be used as a surrogate marker for improving the diagnosis of dementia.