Contributions
Abstract: P790
Type: Poster
Abstract Category: RIMS - Neuropsychology and fatigue management
Background: Cognitive-posture interference (CPI) refers to deterioration of balance while performing a concurrent cognitive task. This phenomenon can be estimated as dual-task cost (DTC), i.e. the change in postural sway from single-task (ST) to dual-task (DT) performance. There is emerging evidence that people with multiple sclerosis (MS) may present pathological CPI level compared to general population, with detrimental consequences on their quality of life and increased risk of falls.
Objective: To investigate the disease-altered structure-function relationship underpinning the CPI phenomenon in people with MS.
Methods: We measured the postural sway in quiet standing (ST condition) and while performing the Stroop color-word test (DT condition) of 64 patients and 64 sex- and age-matched healthy controls by a force platform. The patient group also underwent a magnetic resonance imaging scan of the brain with a 1.5T magnet. Brain lesions on T2 and T1-weighted images were outlined by a semi-automated edge contour technique (Jim 7.0 software) to obtain binary T2 and T1-lesion masks and the corresponding lesion volumes (LV). Correlations between behavioural data from the dual-task experiment and lesion location was determined by means of a non-parametric permutation-based approach generating voxel-based lesion symptom maps (VLSM) (MRIcron software).
Results: Patients had larger postural sway in both ST and DT conditions (p-values< 0.001), and a greater DTC (42% vs 28%, p=0.005) than controls. The overall T2-LV correlated neither with patients" postural sway in both ST and DT conditions nor with the DTC of balance (p-values>0.10). There were moderate correlations between T1-LV and postural sway in both ST and DT conditions (rho=0.334 and rho=0.442, respectively; p-values< 0.01) and a weak correlation between T1-LV and DTC of balance (rho=0.254; p=0.045). We found clusters of T2 lesions in distinct anatomical regions (anterior corona radiata, sagittal stratum, posterior thalamic radiations, bilaterally) to be correlated with DTC of balance (p< 0.01 false discovery rate-corrected). The VLSM did not reveal any significant association with behavioural data using T1-lesion masks.
Discussion: Our findings suggest that the CPI phenomenon in MS has multifactorial causes, including neurodegenerative processes driven by chronic axonal loss and disconnection along specific areas implicated in visuo-spatial attention and task-switching abilities.
Disclosure:
Funded by AISM/FISM (grant 2014/R/17) and Sapienza University (grant C26A15PS9H)
SR: nothing to disclose.
FF: nothing to disclose.
LC: consulting fees from Almirall.
NP: speaker honoraria from Biogen.
LDG: nothing to disclose.
LP: consulting fees from Biogen and Novartis; speaker honoriaria from Biogen, Genzyme, Novartis, Teva; research grants from Genzyme.
Abstract: P790
Type: Poster
Abstract Category: RIMS - Neuropsychology and fatigue management
Background: Cognitive-posture interference (CPI) refers to deterioration of balance while performing a concurrent cognitive task. This phenomenon can be estimated as dual-task cost (DTC), i.e. the change in postural sway from single-task (ST) to dual-task (DT) performance. There is emerging evidence that people with multiple sclerosis (MS) may present pathological CPI level compared to general population, with detrimental consequences on their quality of life and increased risk of falls.
Objective: To investigate the disease-altered structure-function relationship underpinning the CPI phenomenon in people with MS.
Methods: We measured the postural sway in quiet standing (ST condition) and while performing the Stroop color-word test (DT condition) of 64 patients and 64 sex- and age-matched healthy controls by a force platform. The patient group also underwent a magnetic resonance imaging scan of the brain with a 1.5T magnet. Brain lesions on T2 and T1-weighted images were outlined by a semi-automated edge contour technique (Jim 7.0 software) to obtain binary T2 and T1-lesion masks and the corresponding lesion volumes (LV). Correlations between behavioural data from the dual-task experiment and lesion location was determined by means of a non-parametric permutation-based approach generating voxel-based lesion symptom maps (VLSM) (MRIcron software).
Results: Patients had larger postural sway in both ST and DT conditions (p-values< 0.001), and a greater DTC (42% vs 28%, p=0.005) than controls. The overall T2-LV correlated neither with patients" postural sway in both ST and DT conditions nor with the DTC of balance (p-values>0.10). There were moderate correlations between T1-LV and postural sway in both ST and DT conditions (rho=0.334 and rho=0.442, respectively; p-values< 0.01) and a weak correlation between T1-LV and DTC of balance (rho=0.254; p=0.045). We found clusters of T2 lesions in distinct anatomical regions (anterior corona radiata, sagittal stratum, posterior thalamic radiations, bilaterally) to be correlated with DTC of balance (p< 0.01 false discovery rate-corrected). The VLSM did not reveal any significant association with behavioural data using T1-lesion masks.
Discussion: Our findings suggest that the CPI phenomenon in MS has multifactorial causes, including neurodegenerative processes driven by chronic axonal loss and disconnection along specific areas implicated in visuo-spatial attention and task-switching abilities.
Disclosure:
Funded by AISM/FISM (grant 2014/R/17) and Sapienza University (grant C26A15PS9H)
SR: nothing to disclose.
FF: nothing to disclose.
LC: consulting fees from Almirall.
NP: speaker honoraria from Biogen.
LDG: nothing to disclose.
LP: consulting fees from Biogen and Novartis; speaker honoriaria from Biogen, Genzyme, Novartis, Teva; research grants from Genzyme.