Mechanisms of motoric cognitive risk—Hypotheses based on a systematic review and meta‐analysis of longitudinal cohort studies of older adults

Abstract

We aimed to refine the hypothesis that motoric cognitive risk (MCR), a syndrome combining measured slow gait speed and self-reported cognitive complaints, is prognostic of incident dementia and other major causes of morbidity in older age. We propose mechanisms on the relationship between motor and cognitive function and describe a roadmap to validate these hypotheses. We systematically searched major electronic databases from inception to August 2021 for original longitudinal cohort studies of adults aged ≥60 years that compared an MCR group to a non-MCR group with any health outcome. Fifteen cohorts were combined by meta-analysis. Participants with MCR were at an increased risk of cognitive impairment (adjusted hazard ratio [aHR]

Using Interaction between Cognitive and Motor Impairment for Risk Screening of Major Neurocognitive Disorders: Results of the EPIDOS Observational Cohort Study

“…Our findings also revealed that the association between both items (i.e., inability to name the date and use of a walking aid and/or history of falls) and incident MNCD was significant and greater when combined, compared to the inability to name the date by itself. Again, this result is consistent with previous results reported on MCR [ 9 , 10 ]. Indeed, we report that the magnitude of this risk is two-fold when compared to the cognitive impairment item alone.…”

“…In our study, selected participants were free of MNCD at baseline and only those with temporal impairment had significant risk of incident MNCD. Although specific motor impairment related to gait disorders or mild parkinsonian signs may predict cognitive decline, the association between cognitive impairment and incident MNCD is stronger than between motor impairment and incident MNCD [ 7 , 8 , 9 ]. Finally, there are more mixed results regarding the association between motor impairment and incident MNCD compared to cognitive impairment [ 7 , 8 , 9 , 10 ].…”

“…Cognitive impairment is a risk factor of motor impairment and vice versa [ 1 , 3 , 4 , 5 , 6 , 7 , 8 ]. In addition, when they coexist, the risk of MNCD increases significantly [ 8 , 9 , 10 ]. The co-occurrence of slow walking speed and subjective cognitive complaint (SCC) in individuals free of MNCD defines motoric cognitive risk syndrome (MCR) [ 8 ].…”

“…The co-occurrence of slow walking speed and subjective cognitive complaint (SCC) in individuals free of MNCD defines motoric cognitive risk syndrome (MCR) [ 8 ]. MCR is a pre-MNCD stage and poses a greater risk of MNCD than each MCR component considered individually [ 8 , 9 ], suggesting a synergistic effect which may be used to screen MNCD in the older population [ 10 ].…”

Prevalence and predictors of Motoric Cognitive Risk syndrome in a community-dwelling older Scottish population: a longitudinal observational study

“…A 2022 systematic review and meta-analysis found that, compared to those without MCR, those with MCR are at over twice the risk of developing dementia after 4.3 years of follow-up and 76% more likely to develop cognitive impairment after 5.6 years of follow up. 7 MCR is also prognostic of future falls and earlier mortality. 7…”