Aerobic fitness and hippocampal volume in multiple sclerosis
RW Motl1, B Sutton1, E Hubbard1, N Sreekumar1, LA Pilutti1
1University of Illinois at Urbana-Champaign, Urbana, IL, United States
Background: The hippocampus is important for memory functions in multiple sclerosis (MS). Importantly, there is significant atrophy of this structure among persons with MS, and the volume of the hippocampus has been inversely associated with performance on tests of memory encoding. There is substantial evidence that aerobic fitness and exercise training yield improvements in hippocampal volume among older adults without MS, and one recent case study suggested similar benefits in MS. There is a need for additional evidence of an association between aerobic fitness and hippocampal volume before investing considerable time, effort, and resources into clinical trials of aerobic exercise training in MS.
Objectives: This study examined the association between aerobic fitness and hippocampal volume in persons with MS.
Methods: We enrolled 25 persons with MS (EDSS = 1.0-6.5) who underwent an incremental exercise test on an electrically-braked, Lode cycle ergometer for objectively quantifying aerobic fitness as peak power output (Wp). Participants further underwent MRI using a 3T whole body MRI Siemens Trio scanner. Using 3D T1-weighted MR images, volumes of the right and left hippocampi were automatically calculated by the FMRIB's Integrated Registration and Segmentation Tool (FIRST)-algorithm FMRIB's Software Library (FSL). We examined the association using Spearman rho bivariate (rs) and partial (prs) correlations controlling for age and EDSS scores.
Results: Wp was significantly associated with the average hippocampal volume (rs=.41) and EDSS scores (rs=-.77), but not age (rs=-.31). The correlations were not statistically significant between hippocampal volume with age (rs=-.15) or EDSS scores (rs=-.12). The correlation between Wp and average hippocampal volume was independent of age and EDSS scores (prs=.50).
Conclusions: We provide novel evidence of an association between aerobic fitness and hippocampal volume, independent of age and disability status, in MS. This provides a stronger basis for examining aerobic exercise training as an approach for delaying or reversing atrophy of the hippocampus in MS.
RW Motl1, B Sutton1, E Hubbard1, N Sreekumar1, LA Pilutti1
1University of Illinois at Urbana-Champaign, Urbana, IL, United States
Background: The hippocampus is important for memory functions in multiple sclerosis (MS). Importantly, there is significant atrophy of this structure among persons with MS, and the volume of the hippocampus has been inversely associated with performance on tests of memory encoding. There is substantial evidence that aerobic fitness and exercise training yield improvements in hippocampal volume among older adults without MS, and one recent case study suggested similar benefits in MS. There is a need for additional evidence of an association between aerobic fitness and hippocampal volume before investing considerable time, effort, and resources into clinical trials of aerobic exercise training in MS.
Objectives: This study examined the association between aerobic fitness and hippocampal volume in persons with MS.
Methods: We enrolled 25 persons with MS (EDSS = 1.0-6.5) who underwent an incremental exercise test on an electrically-braked, Lode cycle ergometer for objectively quantifying aerobic fitness as peak power output (Wp). Participants further underwent MRI using a 3T whole body MRI Siemens Trio scanner. Using 3D T1-weighted MR images, volumes of the right and left hippocampi were automatically calculated by the FMRIB's Integrated Registration and Segmentation Tool (FIRST)-algorithm FMRIB's Software Library (FSL). We examined the association using Spearman rho bivariate (rs) and partial (prs) correlations controlling for age and EDSS scores.
Results: Wp was significantly associated with the average hippocampal volume (rs=.41) and EDSS scores (rs=-.77), but not age (rs=-.31). The correlations were not statistically significant between hippocampal volume with age (rs=-.15) or EDSS scores (rs=-.12). The correlation between Wp and average hippocampal volume was independent of age and EDSS scores (prs=.50).
Conclusions: We provide novel evidence of an association between aerobic fitness and hippocampal volume, independent of age and disability status, in MS. This provides a stronger basis for examining aerobic exercise training as an approach for delaying or reversing atrophy of the hippocampus in MS.