Cognitive performance predictors of incident motoric cognitive risk syndrome

Abstract

AbstractBackgroundMotoric cognitive risk syndrome (MCR) is a gait based pre‐dementia syndrome that builds on operational definitions of mild cognitive impairment (MCI), and is associated with increased risk for Alzheimer’s Disease and other types of dementia. Declines in cognitive function associated with risk of developing MCR have not been established. We aimed to examine the association between cognitive performance on tests of memory and executive function (EF) and related processes and risk of incident MCR.MethodOf the 541 non‐demented participants (aged 65+) in a community‐based cohort, at baseline 22 met criteria for MCR, 58 for MCI, and 17 met criteria for both MCR and MCI, and were excluded from the analyses. Cognitive performance was measured using seven tests: the free recall score from the Free and Cued Selective Reminding Test, Figure Recall from the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), Story Recall from the RBANS, Category Fluency, Controlled Oral Word Association Test, Digit Symbol Substitution test and Trail Making Test part B. A confirmatory factor analysis indicated that these cognitive tests fell into two categories of cognitive function: memory and EF and related processes. Cox proportional hazard models adjusted for age, sex and education was used to examine the association between cognitive test performance and incident MCR in 444 participants. For the purpose of comparison, we also examined the association between cognitive performance and MCI.ResultOver a mean follow‐up of 3.0 years, 37 participants developed incident MCR and 69 incident MCI. Performance on tests of EF and related processes was associated with risk for MCR (adjusted hazard ratios (aHR) ranging from 0.96 to 0.99). One memory test (free recall) was associated with risk of MCR (aHR: 0.94, 95% Confidence Interval: 0.89‐0.99). Performance on all tests of memory (aHR ranging from 0.81 to 0.92) and EF and related processes (HR ranging from 0.94 to 0.99) was associated with increased risk of MCI.ConclusionCognitive performance on tests of EF and related processes are associated with increased risk of MCR. This may be indicative of a distinct underlying pathology in patients who are at risk of MCR.