“Cognitive” Criteria in Older Adults with Slow Gait Speed: Implications for Motoric Cognitive Risk Syndrome

Abstract Background Motoric Cognitive Risk Syndrome (MCR) is a predementia condition that combines slow gait speed and subjective cognitive concerns (SCC). The SCC criterion is presently unstandardized, possibly limiting risk detection. We sought to: 1. Characterize SCC practices through MCR literature review; 2. Investigate the ability of SCC in slow gait individuals in predicting the likelihood of cognitive impairment in a demographically diverse sample of community-dwelling, non-demented older adults. Methods First, we comprehensively reviewed the MCR literature, extracting information regarding SCC measures, items, sources, and cognitive domain. Next, Einstein Aging Study (EAS) participants (N=278, Mage=77.22±4.74, %female=67, Meducation=15±3.61, %non-Hispanic white=46.3) completed gait, Clinical Dementia Rating Scale (CDR), and SCC assessment at baseline and annual follow-up (Mfollow-up=3.5). Forty-two participants met slow gait criteria at baseline. Generalized linear mixed effects models examined baseline SCC to predict cognitive impairment on CDR over follow-up. Results We reviewed all published MCR studies (N=106) and documented ambiguity in SCC criteria, with a prevalent approach being use of a single self-reported memory item. In EAS, high SCC endorsement on a comprehensive, validated screen significantly impacted the rate of cognitive impairment (CDR; βinteraction=0.039, p=0.018) in slow gait individuals. Conclusions An assessment approach that queries across numerous SCC domains was found to predict future decline in clinical dementia status in slow gait older adults. Current SCC practices in MCR, which tend to utilize a single memory item, may not be the optimal approach. We discuss the implications of SCC criteria validation and standardization to enhance early dementia detection in MCR.