Contributions
Abstract: P1093
Type: Poster
Abstract Category: Pathology and pathogenesis of MS - Neurophysiology
Background: Majority multiple sclerosis (MS) patients experience balance problems during the disease course. Subtle cognitive deficits are present in almost half of the patients at the beginning of the disease. To assess motor-cognitive interference, we studied postural performance under dual-tasking in patients with clinically isolated syndrome (optic neuritis-ON) suggestive of MS.
Methods: Within 3 months from unilateral ON we prospectively included 20 patients with regained visual acuity of 0.8 or more (age 33.4±12.8; EDSS 1±1, number of MRI lesions: min 0, max>30). We also included 20 age, weight, height and education matched healthy subjects. Balance was studied by static posturography and centre of pressure (COP) measures. Posturography was performed with eyes closed and feet together in three conditions: standing, standing+Brooks´ (BR) spatial memory task and standing+2-back verbal memory task (2B). Each trial lasted 120s, middle 90 seconds were analysed. Total COP path, maximal COP velocity, medio-lateral (m-l) and antero-posterior (a-p) sway amplitudes were measured. For each cognitive task percentage change of accuracy was calculated while dual-tasking in reference to single-task performance. Repeated measures ANOVA was used to analyse data.
Results: There was no difference in COP path or maximal COP velocity between the groups (p=0.3, p=0.2), however the response to dual tasking differed between the groups for both variables (p=0.01, p=0.02). Post-hoc analyses showed patients significantly decreased COP path and maximal COP velocity while performing br (p=0.004, p=0.02), compared to standing alone. This was not the case for 2b. There were no differences in m-l sway amplitudes (p=0.2) neither in response to different dual task condition (p=0.1) observed between the groups. The same was observed for a-p sway amplitudes (p=0.9, p=0.8). There was no difference in average % change of performance on each cognitive task while dual tasking (4% for 2b and br), compared to cognitive task alone. The same was observed in healthy subjects (3% for 2b; 1% for br).
Conclusion: Our results show that visual working memory load affects postural performance in patients with ON suggestive of MS compared to healthy subjects, while this is not the case for verbal working memory. Such results suggest that disease might affect visuo-spatial and motor information integration at its earliest stages where there is little or no motor or cognitive deficits observed.
Disclosure: Gregor Brecl Jakob: nothing to disclose
Saša Šega: nothing to disclose
Alenka Horvat Ledinek: nothing to disclose
Matej Baruca: nothing to disclose
Uroš Rot: nothing to disclose
Abstract: P1093
Type: Poster
Abstract Category: Pathology and pathogenesis of MS - Neurophysiology
Background: Majority multiple sclerosis (MS) patients experience balance problems during the disease course. Subtle cognitive deficits are present in almost half of the patients at the beginning of the disease. To assess motor-cognitive interference, we studied postural performance under dual-tasking in patients with clinically isolated syndrome (optic neuritis-ON) suggestive of MS.
Methods: Within 3 months from unilateral ON we prospectively included 20 patients with regained visual acuity of 0.8 or more (age 33.4±12.8; EDSS 1±1, number of MRI lesions: min 0, max>30). We also included 20 age, weight, height and education matched healthy subjects. Balance was studied by static posturography and centre of pressure (COP) measures. Posturography was performed with eyes closed and feet together in three conditions: standing, standing+Brooks´ (BR) spatial memory task and standing+2-back verbal memory task (2B). Each trial lasted 120s, middle 90 seconds were analysed. Total COP path, maximal COP velocity, medio-lateral (m-l) and antero-posterior (a-p) sway amplitudes were measured. For each cognitive task percentage change of accuracy was calculated while dual-tasking in reference to single-task performance. Repeated measures ANOVA was used to analyse data.
Results: There was no difference in COP path or maximal COP velocity between the groups (p=0.3, p=0.2), however the response to dual tasking differed between the groups for both variables (p=0.01, p=0.02). Post-hoc analyses showed patients significantly decreased COP path and maximal COP velocity while performing br (p=0.004, p=0.02), compared to standing alone. This was not the case for 2b. There were no differences in m-l sway amplitudes (p=0.2) neither in response to different dual task condition (p=0.1) observed between the groups. The same was observed for a-p sway amplitudes (p=0.9, p=0.8). There was no difference in average % change of performance on each cognitive task while dual tasking (4% for 2b and br), compared to cognitive task alone. The same was observed in healthy subjects (3% for 2b; 1% for br).
Conclusion: Our results show that visual working memory load affects postural performance in patients with ON suggestive of MS compared to healthy subjects, while this is not the case for verbal working memory. Such results suggest that disease might affect visuo-spatial and motor information integration at its earliest stages where there is little or no motor or cognitive deficits observed.
Disclosure: Gregor Brecl Jakob: nothing to disclose
Saša Šega: nothing to disclose
Alenka Horvat Ledinek: nothing to disclose
Matej Baruca: nothing to disclose
Uroš Rot: nothing to disclose