Test-Retest Reliability of Cognitive-Motor Interference Assessments in Walking With Various Task Complexities in Persons With Multiple Sclerosis

Abstract

Background: Simultaneous execution of motor and cognitive tasks can result in worsened performance on one or both tasks, indicating cognitive motor interference (CMI). A growing amount of research on CMI in persons with Multiple Sclerosis (pwMS) is observed. However, psychometric properties of dual-task outcomes have been scarcely reported.Objective: To investigate the between-day test-retest reliability of the motor and cognitive dual-task costs (DTC) during multiple CMI test conditions with various task complexity in pwMS and matched healthy controls (HC).Methods: 34 pwMS (Expanded Disability Status Scale score 3.0±0.8) and 31 HCs were tested and retested on three single cognitive, four single motor and twelve cognitivemotor dual-tasks. Cognitive tasks included serial subtraction by seven, titrated digit span backwards and auditory vigilance. Motor tasks were walking: at self-selected speed, over obstacles, crisscross and while carrying a water-filled cup. Outcome measures were cognitive and motor DTC, calculated as percentage change of dualtask performance compared to single-task performance. Intraclass correlations (ICCs) and Spearman correlation coefficients were calculated as appropriate.Results: For DTCmotor of gait speed, ICCs ranged from 0.45 to 0.81 and Spearman correlations from 0.74 to 0.82. For DTCcognitive, ICCs ranged from -0.18 to 0.49 and Spearman correlations from -0.28 to 0.26. Reliability depended on the type of motor and cognitive task.Conclusion: Reliability of the DTCmotor was, overall, good, while that of the DTCcognitive was poor. The 'walking' and 'cup' dual-task conditions were the most reliable regardless of the integrated cognitive task.3

Structured Cognitive-Motor Dual Task Training Compared to Single Mobility Training in Persons with Multiple Sclerosis, a Multicenter RCT

“…Surprisingly, no improvements were found on patient-reported experiences of dual tasking in daily life as measured by the questionnaire. It might be that the effects found in the dual task measures were not big enough to be clinically relevant, as the changes in DTC motor in the present study were lower than the previously reported minimal detectable change of approximately 12% for the DTC motor [22]. Other explanations of the lack of improvement on the dual task questionnaire might be that the activities in daily life are still somehow different from the dual tasks used in the current study (e.g.…”

“…Other studies however did find a difference between DTT and single task training on cognitive dual task performance in Parkinson disease patients [39] and elderly subjects [12]. Although the cognitive tasks used in the present study are conventional in literature, the DTC cognitive recently demonstrated low reliability and learning effects in pwMS, perhaps explaining part of these results [22].…”

“…Participants also performed a fourth motor task, namely walking crisscross. However, as a recent study showed that performance on the 'crisscross' condition quantified by 'turning velocity' could not be reliably measured in persons with MS [22], these conditions were excluded from analysis in the present study. Similarly, results on the cognitive tasks is only shortly reported upon.…”

The patients’ perspective on the perceived difficulties of dual-tasking: development and validation of the Dual-task Impact on Daily-living Activities Questionnaire (DIDA-Q)

“…A recent meta-analysis on CMI showed that walking speed changes due to DT can differentiate healthy participants from those with neurological deficit (Al-Yahya et al, 2011), supporting the clinical utility of DT outcomes to detect and measure disability, disease progression and intervention effectiveness. Although in its infancy with respect to other neurological conditions, DT literature in MS showed promising results, both as assessment and rehabilitative methods (Veldkamp et al, 2019;Veldkamp et al, 2019b).…”

Design, Development, and Testing of an App for Dual-Task Assessment and Training Regarding Cognitive-Motor Interference (CMI-APP) in People With Multiple Sclerosis: Multicenter Pilot Study

“…For example, people with MS showed a greatly increased postural sway and a large decrement in variability of anteroposterior and mediolateral sway velocity while executing a simple arithmetic task during balance maintenance as compared with controls [14,15]. Similarly, they showed increased stride time and decreased walking speed during walking under several cognitive conditions (ie, talking) [16][17][18]. Recently, findings regarding cognitive-motor performances were reported during upper limb tasks [19].…”