Gait Dysfunction in Motoric Cognitive Risk Syndrome

Background: Motoric cognitive risk (MCR) syndrome is a cognitive-motor syndrome associated with increased risk of transition to dementia. The clinical phenotype of MCR is not yet established. Objective: To systematically assess clinical gait abnormalities in older adults with MCR. Methods: Of the 522 community-dwelling non-demented adults aged 65 and older enrolled in the Central Control of Mobility in Aging study, 43 were diagnosed with MCR (47% women) based on presence of cognitive complaints and slow gait velocity (MCRv). Four additional subtypes of MCR were defined by substituting slow gait with short stride length (MCRsl, n=41), slow swing time (MCRsw, n=21), high stride length variability (MCRslv, n=24), and high swing time variability (MCRswv, n=25). The prevalence of clinical gait abnormalities (neurological or non-neurological) in MCR overall (n=81) and subtypes was studied. We also examined if gait abnormalities predicted further cognitive and functional decline in MCR cases. Results: Most clinical gait abnormalities were mild (walked without assistance) in the five MCR subtypes (44 to 61%). Neurological (range 24 to 46%) and non-neurological gait abnormalities (33 to 61%) were common in all MCR subtypes. Neurological gaits were most frequent in MCRsl (46%) and non-neurological gaits in MCRv (61%). Over a median 3.02 years of follow-up, presence of gait abnormality in MCR cases at baseline predicted worsening disability scores (estimate 0.17, p-value=0.033) but not decline on cognitive scores (p-value=0.056). Conclusion: Clinical gait abnormalities are common in MCR syndrome and its subtypes, and are associated with accelerated functional decline.