Motoric cognitive risk syndrome: multicountry prevalence and dementia risk

Abstract

Objectives: Our objective is to report prevalence of motoric cognitive risk syndrome (MCR), a newly described predementia syndrome characterized by slow gait and cognitive complaints, in multiple countries, and its association with dementia risk.

Methods: Pooled MCR prevalence analysis of individual data from 26,802 adults without dementia and disability aged 60 years and older from 22 cohorts from 17 countries. We also examined risk of incident cognitive impairment (Mini-Mental State Examination decline ≥4 points) and dementia associated with MCR in 4,812 individuals without dementia with baseline Mini-Mental State Examination scores ≥25 from 4 prospective cohort studies using Cox models adjusted for potential confounders.

Results: At baseline, 2,808 of the 26,802 participants met MCR criteria. Pooled MCR prevalence was 9.7% (95% confidence interval [CI] 8.2%-11.2%). MCR prevalence was higher with older age but there were no sex differences. MCR predicted risk of developing incident cognitive impairment in the pooled sample (adjusted hazard ratio [aHR] 2.0, 95% CI 1.7-2.4); aHRs were 1.5 to 2.7 in the individual cohorts. MCR also predicted dementia in the pooled sample (aHR 1.9, 95% CI 1.5-2.3). The results persisted even after excluding participants with possible cognitive impairment, accounting for early dementia, and diagnostic overlap with other predementia syndromes.

Conclusion: MCR is common in older adults, and is a strong and early risk factor for cognitive decline. This clinical approach can be easily applied to identify high-risk seniors in a wide variety of settings.

© 2014 American Academy of Neurology.

Figures

Figure 1. Prevalence of motoric cognitive risk syndrome

Prevalence estimates (ES) for each study are graphically represented by small diamonds and 95% CIs by horizontal bars. Gray boxes surrounding the diamonds graphically represent study weighting in the analysis, which is also shown in the last column. The large diamond is the pooled prevalence estimate. Pooled effect estimate was similar for random- and fixed-effects model. The vertical dotted line represents the prevalence estimates of the pooled result. CCMA = Central Control of Mobility in Aging; CI = confidence interval; MAP = Memory and Aging Project; ROS = Religious Orders Study; SAGE = Study on Global Ageing and Adult Health.

Figure 2. MCR and risk of incident cognitive impairment (A) and dementia (B)

Kaplan-Meier survival curves with 95% confidence interval over 12 years’ follow-up in pooled samples. MCR = motoric cognitive risk syndrome.