Motor-Cognitive Dual Task Not Associated With Cognitive Dysfunction in Parkinson’s

Current evidence does not support an association between motor-cognitive dual task (DT) gait performance and cognitive impairment in patients with Parkinson disease (PD), according a study published in Frontiers in Neurology.

A total of 67 people with PD participated in the study. All completed gait tests. The authors analyzed patient cognitive function, single task, and DT gait performance. The Montreal Cognitive Assessment (MoCA) was used to evaluate cognitive function, with cognitive impairment being defined as a MoCA score of <26.

The investigators also used a correlation analysis to understand the correlations between MoCA performance and gait parameters. Additionally, the investigators correlated cognitive performance with DT gait costs and clinical confounders. These confounders included gender, disease duration, age, motor impairment, medication, and depression.

According to the correlation analysis, the researchers found weak correlations between the DT costs of gait parameters and MoCA score (r/r_Sp ≤ 0.3). In addition, the researchers found that parameters of DT costs of maximum toe clearance, swing time variability, and stride length (|r/r_Sp| > 0.2) in the regression analysis explained approximately 8% of the variation in cognition.

The regression analysis did reveal that these gait parameters explained approximately 30% of MoCA performance when combined with the clinical confounders. A total of 42 patients were subdivided by MoCA cut-off scores of <26 (n=21) and ≥26 (n=21). There were strong DT effects within both groups with large effect sizes; however, the researchers observed no significant between-group effects with regard to DT gait costs.

Although the investigators recorded the DT costs for gait parameters, they did not record the DT costs for the cognitive task. As a result, the researchers suggest that the prioritization of cognitive and motor tasks may differ among those with PD.

The investigators recommend extensive neuropsychological test batteries instead of MoCA in some situations, as the MoCA global cognitive assessment tool may not be “sensitive enough to detect executive functions responsible for DT gait performance in PD.”

Reference

Gaßner H, Marxreiter F, Steib S, et al. Gait and cognition in Parkinson’s disease: cognitive impairment is inadequately reflected by gait performance during dual task. Front Neurol. 2017;8:550.