Interlimb arm-swing asymmetry during dual-task gait has prognostic value for cognitive decline in Parkinson’s disease

Research Objectives: To determine if dual-task (DT) gait parameters are predictive of cognitive decline in Parkinson’s disease (PD).

Design: A retrospective one-year longitudinal cohort study of individuals with PD from Parkinson’s Progression Markers Initiative was conducted. The following data were extracted at baseline: spatiotemporal DT gait parameters, demographics (age, sex), PD symptoms (Hoehn & Yahr, time since diagnosis), motor function (Movement Disorder Society Unified Parkinson’s Disease Rating Scale), and cognition (Montreal Cognitive Assessment (MoCA)). MoCA scores at one-year were also extracted.

Setting: Academic research facility

Participants: 65 participants with PD

Interventions: None

Main Outcome Measures: MoCA change from baseline to one-year, dichotomized into cognitive decliners and non-decliners.

Results: A stepwise discriminant function analysis (DFA) on change in MoCA was conducted, inputting all DT gait parameters as predictor variables. DT interlimb arm swing asymmetry (ASA) was the most incompatible with the null (p <.001), such that individuals with more asymmetry were more likely to be cognitive decliners, correctly classifying 66.2% of cases. Next, a DFA was conducted on change in MoCA, inputting demographic, PD symptoms, motor function, and baseline MoCA as covariates, with ASA as the predictor variable. This model correctly classified 77.4% of cases, with ASA being the only baseline predictor suggesting incompatibility with the null (p <.001). In a subsequent hierarchical logistic regression using the same model (χ2(6)=15.291, p=.018) ASA demonstrated an odds ratio such that a 10% increase in asymmetry was associated with 1.70 increased odds of cognitive decline.

Conclusions: Individuals with greater ASA during DT gait are more likely to have a decline in cognition within a year. Increased ASA during DT signifies a decline in automaticity and potentially indicates subtle changes in cognition that may precede further cognitive decline. DT arm swing may provide clinicians and rehabilitation specialists an opportunity to identify individuals more likely to develop cognitive impairment.

Author(s) Disclosures: The authors declare that they have no disclosures or conflicts of interest.