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Jeffrey M Hausdorff - One of the best experts on this subject based on the ideXlab platform.
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can tai chi training impact fractal Stride Time dynamics an index of gait health in older adults cross sectional and randomized trial studies
PLOS ONE, 2017Co-Authors: Jeffrey M Hausdorff, Brad Manor, Lewis A Lipsitz, Eric A Macklin, Paolo Bonato, Vera Novak, Chungkang Peng, Peter M WayneAbstract:Purpose To determine if Tai Chi (TC) has an impact on long-range correlations and fractal-like scaling in gait Stride Time dynamics, previously shown to be associated with aging, neurodegenerative disease, and fall risk. Methods Using Detrended Fluctuation Analysis (DFA), this study evaluated the impact of TC mind-body exercise training on Stride Time dynamics assessed during 10 minute bouts of overground walking. A hybrid study design investigated long-term effects of TC via a cross-sectional comparison of 27 TC experts (24.5 ± 11.8 yrs experience) and 60 age- and gender matched TC-naive older adults (50–70 yrs). Shorter-term effects of TC were assessed by randomly allocating TC-naive participants to either 6 months of TC training or to a waitlist control. The alpha (α) long-range scaling coefficient derived from DFA and gait speed were evaluated as outcomes. Results Cross-sectional comparisons using confounder adjusted linear models suggest that TC experts exhibited significantly greater long-range scaling of gait Stride Time dynamics compared with TC-naive adults. Longitudinal random-slopes with shared baseline models accounting for multiple confounders suggest that the effects of shorter-term TC training on gait dynamics were not statistically significant, but trended in the same direction as longer-term effects although effect sizes were very small. In contrast, gait speed was unaffected in both cross-sectional and longitudinal comparisons. Conclusion These preliminary findings suggest that fractal-like measures of gait health may be sufficiently precise to capture the positive effects of exercise in the form of Tai Chi, thus warranting further investigation. These results motivate larger and longer-duration trials, in both healthy and health-challenged populations, to further evaluate the potential of Tai Chi to restore age-related declines in gait dynamics. Trial registration The randomized trial component of this study was registered at ClinicalTrials.gov (NCT01340365).
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tai chi training may reduce dual task gait variability a potential mediator of fall risk in healthy older adults cross sectional and randomized trial studies
Frontiers in Human Neuroscience, 2015Co-Authors: Jeffrey M Hausdorff, Lewis A Lipsitz, Eric A Macklin, Vera Novak, Chungkang Peng, Peter M Wayne, Matthew Lough, Brad ManorAbstract:BACKGROUND: Tai Chi (TC) exercise improves balance and reduces falls in older, health-impaired adults. TC’s impact on dual task (DT) gait parameters predictive of falls, especially in healthy active older adults, however, is unknown. PURPOSE: To compare differences in usual and DT gait between long-term TC-expert practitioners and age-/gender-matched TC-naive adults, and to determine the effects of short-term TC training on gait in healthy, non-sedentary older adults. METHODS: A cross-sectional study compared gait in healthy TC-naive and TC-expert (24.5±12 yrs experience) older adults. TC-naive adults then completed a 6-month, two-arm, wait-list randomized clinical trial of TC training. Gait speed and Stride Time variability (%) was assessed during 90 sec trials of undisturbed and cognitive DT (serial-subtractions) conditions. RESULTS: During DT, gait speed decreased (p<0.003) and Stride Time variability increased (p<0.004) in all groups. Cross-sectional comparisons indicated that Stride Time variability was lower in the TC-expert vs. TC-naive group, significantly so during DT (2.11% vs. 2.55%; p=0.027); in contrast, gait speed during both undisturbed and DT conditions did not differ between groups. Longitudinal analyses of TC-naive adults randomized to 6 months of TC training or usual care identified improvement in DT gait speed in both groups. A small improvement in DT Stride Time variability (effect size = 0.2) was estimated with TC training, but no significant differences between groups were observed. Potentially important improvements after TC training could not be excluded in this small study. CONCLUSIONS: In healthy active older adults, positive effects of short- and long-term TC were observed only under cognitively challenging DT conditions and only for Stride Time variability. DT Stride variability offers a potentially sensitive metric for monitoring TC’s impact on fall risk with healthy older adults.
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treadmill walking as an external pacemaker to improve gait rhythm and stability in parkinson s disease
Movement Disorders, 2005Co-Authors: Silvi Frenkeltoledo, Chava Peretz, Leor Gruendlinger, Talia Herman, Nir Giladi, Jeffrey M HausdorffAbstract:Recent reports suggest that external cueing improves Stride length and gait speed in Parkinson's disease (PD). The purpose of the present study was to examine the influence of treadmill walking on gait variability. The 36 PD patients (Hoehn and Yahr stage 2–2.5) were compared to 30 controls. Subjects walked three Times for 2 minutes each: (1) walking on level ground (unassisted), (2) walking on level ground while using a walker, and (3) walking on a treadmill. Stride Time variability and swing Time variability were significantly increased in the patients compared to the control subjects when walking on level ground with a walker. In both groups, the use of a walking aid did not significantly affect Stride Time variability or swing Time variability, but the treadmill reduced Stride Time variability and swing Time variability in the patients and in the controls. These results indicate that, during treadmill walking, PD subjects are able to walk with a less variable and more stable gait. Because the treadmill walking speed was set to the gait speed on level ground and because this effect was not seen with a walking aid, we suggest that the treadmill may be acting as an external cue to enhance gait rhythmicity and reduce gait variability. © 2005 Movement Disorder Society
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Effect of gait speed on gait rhythmicity in Parkinson's disease: variability of Stride Time and swing Time respond differently
Journal of NeuroEngineering and Rehabilitation, 2005Co-Authors: Silvi Frenkel-toledo, Chava Peretz, Leor Gruendlinger, Talia Herman, Nir Giladi, Jeffrey M HausdorffAbstract:Background The ability to maintain a steady gait rhythm is impaired in patients with Parkinson's disease (PD). This aspect of locomotor dyscontrol, which likely reflects impaired automaticity in PD, can be quantified by measuring the Stride-to-Stride variability of gait timing. Previous work has shown an increase in both the variability of the Stride Time and swing Time in PD, but the origins of these changes are not fully understood. Patients with PD also generally walk with a reduced gait speed, a potential confounder of the observed changes in variability. The purpose of the present study was to examine the relationship between walking speed and gait variability. Methods Stride Time variability and swing Time variability were measured in 36 patients with PD (Hoehn and Yahr stage 2–2.5) and 30 healthy controls who walked on a treadmill at four different speeds: 1) Comfortable walking speed (CWS), 2) 80% of CWS 3) 90% of CWS, and 4) 110% of CWS. In addition, we studied the effects of walking slowly on level ground, both with and without a walker. Results Consistent with previous findings, increased variability of Stride Time and swing Time was observed in the patients with PD in CWS, compared to controls. In both groups, there was a small but significant association between treadmill gait speed and Stride Time variability such that higher speeds were associated with lower (better) values of Stride Time variability (p = 0.0002). In contrast, swing Time variability did not change in response to changes in gait speed. Similar results were observed with walking on level ground. Conclusion The present results demonstrate that swing Time variability is independent of gait speed, at least over the range studied, and therefore, that it may be used as a speed-independent marker of rhythmicity and gait steadiness. Since walking speed did not affect Stride Time variability and swing Time variability in the same way, it appears that these two aspects of gait rhythmicity are not entirely controlled by the same mechanisms. The present findings also suggest that the increased gait variability in PD is disease-related, and not simply a consequence of bradykinesia.
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Effect of gait speed on gait rhythmicity in Parkinson's disease: variability of Stride Time and swing Time respond differently
Journal of neuroengineering and rehabilitation, 2005Co-Authors: Silvi Frenkel-toledo, Chava Peretz, Leor Gruendlinger, Talia Herman, Nir Giladi, Jeffrey M HausdorffAbstract:Background: The ability to maintain a steady gait rhythm is impaired in patients with Parkinson's disease (PD). This aspect of locomotor dyscontrol, which likely reflects impaired automaticity in PD, can be quantified by measuring the Stride-to-Stride variability of gait timing. Previous work has shown an increase in both the variability of the Stride Time and swing Time in PD, but the origins of these changes are not fully understood. Patients with PD also generally walk with a reduced gait speed, a potential confounder of the observed changes in variability. The purpose of the present study was to examine the relationship between walking speed and gait variability. Methods: Stride Time variability and swing Time variability were measured in 36 patients with PD (Hoehn and Yahr stage 2–2.5) and 30 healthy controls who walked on a treadmill at four different speeds: 1) Comfortable walking speed (CWS), 2) 80% of CWS 3) 90% of CWS, and 4) 110% of CWS. In addition, we studied the effects of walking slowly on level ground, both with and without a walker. Results: Consistent with previous findings, increased variability of Stride Time and swing Time was observed in the patients with PD in CWS, compared to controls. In both groups, there was a small but significant association between treadmill gait speed and Stride Time variability such that higher speeds were associated with lower (better) values of Stride Time variability (p = 0.0002). In contrast, swing Time variability did not change in response to changes in gait speed. Similar results were observed with walking on level ground. Conclusion: The present results demonstrate that swing Time variability is independent of gait speed, at least over the range studied, and therefore, that it may be used as a speed-independent marker of rhythmicity and gait steadiness. Since walking speed did not affect Stride Time variability and swing Time variability in the same way, it appears that these two aspects of gait rhythmicity are not entirely controlled by the same mechanisms. The present findings also suggest that the increased gait variability in PD is
Olivier Beauchet - One of the best experts on this subject based on the ideXlab platform.
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Association of hippocampal volume with gait variability in pre-dementia and dementia stages of Alzheimer disease: Results from a cross-sectional study.
Experimental gerontology, 2018Co-Authors: Olivier Beauchet, Cyrille P. Launay, Harmehr Sekhon, Maxime Montembeault, Gilles AllaliAbstract:BACKGROUND Decreased hippocampal volume is a biomarker of Alzheimer disease (AD). The association of hippocampal volume with gait variability across the spectrum of AD, especially in early stages, has been few studied. The study aims to examine the association of hippocampal volume with the coefficient of variation (CoV) of Stride Time in individuals with mild and moderate to severe subjective cognitive impairment (SCI), non-amnestic mild cognitive impairment (na-MCI), amnestic mild cognitive impairment (a-MCI), and mild to moderate AD dementia. METHODS 271 individuals (79 mild SCI, 68 moderate to severe SCI, 47 na-MCI, 42 a-MCI and 35 mild to moderate AD dementia) were included in this cross-sectional study. Hippocampal volume was quantified from a three-dimensional T1-weighted MRI. CoV of Stride Time was recorded at self-selected pace with an electronic walkway. Age, sex, body mass index, number of drugs daily taken, history of falls, walking speed, type of MRI scanner, total intracranial volume, and white matter volume abnormality were used as covariates. RESULTS Participants with moderate to severe SCI had a higher CoV of Stride Time compared to those with mild SCI and na-MCI (P
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Association of increased gait variability while dual tasking and cognitive decline: results from a prospective longitudinal cohort pilot study
GeroScience, 2017Co-Authors: Olivier Beauchet, Cyrille P. Launay, Julia Chabot, Elise J. Levinoff, Harmehr Sekhon, Jean-claude Barthélémy, Frédéric Roche, Gilles AllaliAbstract:Dual task-related changes in gait are considered as a sensitive and a specific marker of adverse effects of cognitive impairment on the highest levels of gait control. No study has examined the longitudinal association between gait performance while dual tasking and the occurrence of cognitive decline. This study aims to examine the association of Stride Time parameters (i.e., mean value and coefficient of variation (CoV)) during single and dual tasking with the occurrence of cognitive decline in non-demented older community dwellers. A total of 56 non-demented community dwellers were recruited in a longitudinal prospective cohort study. Mini-Mental Status Examination (MMSE) scores at baseline assessment and at 5-year follow-up assessment, and mean value and CoV of Stride Time at self-selected usual pace, while usual walking and dual tasking (i.e., counting backward and verbal fluency task) at baseline assessment were recorded. Variation (i.e., delta) of MMSE score from baseline to follow-up assessment as well as of Stride Time parameters from single to dual task was used as outcomes. Worse Stride Time values were reported while dual tasking compared to single tasking (P
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Increased gait variability while dual tasking predicts cognitive decline in older adults: a prospective longitudinal cohort pilot study (P6.093)
Neurology, 2017Co-Authors: Olivier Beauchet, Gilles AllaliAbstract:Objective: To examine whether Stride Time variability during single and dual tasking predicts the occurrence of cognitive decline in older community dwellers. Background: Dual-task related changes in gait are considered as a sensitive and a specific maker of adverse effects of cognitive impairment on highest levels of gait control. No study has examined the longitudinal association between gait performance while dual tasking and the occurrence of cognitive decline. Design/Methods: A total of 56 community dwellers were recruited in this longitudinal prospective cohort study. Mean value and coefficient of variation of Stride Time at self-selected usual pace, while usual walking and dual tasking (counting backward and verbal fluency task) at baseline assessment were used as outcomes. Mini Mental Status Examination (MMSE) scores at baseline assessment and at 5-year follow-up assessment were recorded. Age, sex, body mass index, number of medications and educational level were used as covariates. Results: Increased mean value of Stride Time (i.e; worst gait performance) while usual walking was associated with increased delta MMSE (i.e; worst cognitive performance) (P=0.043). Both linear and Cox regressions showed also that increased CoV of Stride Time (i.e; worst gait performance) while performing a verbal fluency task was associated with increased delta MMSE and abnormal MMSE (P≤0.048) but not under the others walking conditions. Conclusions: Increased Stride Time variability while performing a verbal fluency task predicts cognitive decline. These results confirm the strong relationship between gait and cognitive decline, and thus open new perspective in terms of prediction of dementia. Disclosure: Dr. Beauchet has nothing to disclose. Dr. Allali has nothing to disclose.
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Subjective Memory Impairment and Gait Variability in Cognitively Healthy Individuals: Results from a Cross-Sectional Pilot Study.
Journal of Alzheimer's disease : JAD, 2016Co-Authors: Olivier Beauchet, Cyrille P. Launay, Julia Chabot, Elise J. Levinoff, Gilles AllaliAbstract:Increased Stride Time variability has been associated with memory impairment in mild cognitive impairment. Subjective memory impairment (SMI) is considered the earliest clinical stage of Alzheimer's disease (AD). The association between increased Stride Time variability and SMI has not been reported. This study aims to examine the association of Stride Time variability while performing single and dual tasking with SMI in cognitively healthy individuals (CHI). A total of 126 CHI (15 without SMI, 69 with SMI expressed by participants, 10 with SMI expressed by participant's relative, and 32 with SMI expressed by both participants and their relatives) were included in this cross-sectional study. The coefficient of variation (CoV) of Stride Time and walking speed were recorded under usual condition and while counting backwards. Age, gender, body mass index, number of drugs taken daily, use of psychoactive drugs, fear of falling, history of previous falls, and walking speed were used as covariates. The multiple linear regression models showed that greater CoV of Stride Time while counting backwards, but not while single tasking, was associated with a participant's relative SMI (p = 0.038). This study found a specific association between SMI expressed by a participant's relative and a greater CoV of Stride Time (i.e., worse performance) while dual tasking, suggesting that the association between gait variability and memory may be present in the earliest stages of memory impairment. Thus, gait variability under dual-task in individuals with SMI expressed by their relatives can be a potential biomarker of AD.
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Anti-dementia drugs-related changes in gait performance while single and dual tasking in patients with Alzheimer disease: a meta-analysis.
Current Alzheimer research, 2015Co-Authors: Olivier Beauchet, Manuel Montero-odasso, Cédric Annweiler, Cyrille P. Launay, Gilles AllaliAbstract:BACKGROUND: The effects of anti-dementia drugs on gait performance in Alzheimer disease (AD) are questionable. The objective of this meta-analysis was to examine the effects of anti-dementia drugs on the mean value and the coefficient of variation (CoV) of Stride Time among patients with AD while taking into account the type of drugs (i.e., acetylcholinesterase inhibitors [AChEIs] versus memantine) and the walking conditions (i.e., single versus dual-task). METHODS: An English and French Medline search was conducted in March 2015, with no limit of date, using the Medical Subject Headings terms "pharmaceutical preparations" combined with terms "Pharmaceutical preparations" OR "Therapeutic uses" OR "Drug substitution" OR "Drugs essential" OR "Drugs, Generic" OR "Psychotropic drugs" combined with "Delirium" OR "Dementia" OR "Amnestic" OR "Cognitive disorders" AND "Gait" OR "Gait Ataxia" OR "Gait disorders, Neurologic" OR "Gait apraxia". Fixed-effects meta-analyses were used to examine anti-dementia drugs-related changes in mean value and CoV of Stride Time. RESULTS: Of the 66 identified abstracts, 5 (7.6%) were included in the meta-analysis. Inter-group comparison of between-visit change underscored a significant decrease in CoV of Stride Time (P0.06). Intra-group changes in Stride Time parameters following the use of anti-dementia drugs showed a significant decrease for memantine (PCONCLUSIONS: Anti-dementia drugs demonstrated a significant improvement of gait performance with specific class effect depending on the walking conditions and on the type of Stride Time parameters considered. Language: en
Gilles Allali - One of the best experts on this subject based on the ideXlab platform.
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Association of hippocampal volume with gait variability in pre-dementia and dementia stages of Alzheimer disease: Results from a cross-sectional study.
Experimental gerontology, 2018Co-Authors: Olivier Beauchet, Cyrille P. Launay, Harmehr Sekhon, Maxime Montembeault, Gilles AllaliAbstract:BACKGROUND Decreased hippocampal volume is a biomarker of Alzheimer disease (AD). The association of hippocampal volume with gait variability across the spectrum of AD, especially in early stages, has been few studied. The study aims to examine the association of hippocampal volume with the coefficient of variation (CoV) of Stride Time in individuals with mild and moderate to severe subjective cognitive impairment (SCI), non-amnestic mild cognitive impairment (na-MCI), amnestic mild cognitive impairment (a-MCI), and mild to moderate AD dementia. METHODS 271 individuals (79 mild SCI, 68 moderate to severe SCI, 47 na-MCI, 42 a-MCI and 35 mild to moderate AD dementia) were included in this cross-sectional study. Hippocampal volume was quantified from a three-dimensional T1-weighted MRI. CoV of Stride Time was recorded at self-selected pace with an electronic walkway. Age, sex, body mass index, number of drugs daily taken, history of falls, walking speed, type of MRI scanner, total intracranial volume, and white matter volume abnormality were used as covariates. RESULTS Participants with moderate to severe SCI had a higher CoV of Stride Time compared to those with mild SCI and na-MCI (P
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Association of increased gait variability while dual tasking and cognitive decline: results from a prospective longitudinal cohort pilot study
GeroScience, 2017Co-Authors: Olivier Beauchet, Cyrille P. Launay, Julia Chabot, Elise J. Levinoff, Harmehr Sekhon, Jean-claude Barthélémy, Frédéric Roche, Gilles AllaliAbstract:Dual task-related changes in gait are considered as a sensitive and a specific marker of adverse effects of cognitive impairment on the highest levels of gait control. No study has examined the longitudinal association between gait performance while dual tasking and the occurrence of cognitive decline. This study aims to examine the association of Stride Time parameters (i.e., mean value and coefficient of variation (CoV)) during single and dual tasking with the occurrence of cognitive decline in non-demented older community dwellers. A total of 56 non-demented community dwellers were recruited in a longitudinal prospective cohort study. Mini-Mental Status Examination (MMSE) scores at baseline assessment and at 5-year follow-up assessment, and mean value and CoV of Stride Time at self-selected usual pace, while usual walking and dual tasking (i.e., counting backward and verbal fluency task) at baseline assessment were recorded. Variation (i.e., delta) of MMSE score from baseline to follow-up assessment as well as of Stride Time parameters from single to dual task was used as outcomes. Worse Stride Time values were reported while dual tasking compared to single tasking (P
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Does fear of falling predict gait variability in multiple sclerosis
Journal of the Neurological Sciences, 2017Co-Authors: Magali Laidet, François Herrmann, Stéphane Armand, Frédéric Assal, Patrice H Lalive, Gilles AllaliAbstract:Abstract Background Behavioural symptoms and gait disorders are very common in patients with multiple sclerosis. Objective To evaluate the association between fear of falling and gait instability at one year in patients with multiple sclerosis. Methods Thirty-five multiple sclerosis patients were included. Fear of falling was assessed by the Fall Efficacy Scale-International and gait variability with Stride Time variability under single and dual-task conditions at baseline and at one year. Results Baseline fear of falling score was associated with increased Stride Time variability at one year during dual-task condition even after adjustment on covariates. Conclusion Fear of falling is associated with gait variability at one year, especially under dual-task condition.
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Increased gait variability while dual tasking predicts cognitive decline in older adults: a prospective longitudinal cohort pilot study (P6.093)
Neurology, 2017Co-Authors: Olivier Beauchet, Gilles AllaliAbstract:Objective: To examine whether Stride Time variability during single and dual tasking predicts the occurrence of cognitive decline in older community dwellers. Background: Dual-task related changes in gait are considered as a sensitive and a specific maker of adverse effects of cognitive impairment on highest levels of gait control. No study has examined the longitudinal association between gait performance while dual tasking and the occurrence of cognitive decline. Design/Methods: A total of 56 community dwellers were recruited in this longitudinal prospective cohort study. Mean value and coefficient of variation of Stride Time at self-selected usual pace, while usual walking and dual tasking (counting backward and verbal fluency task) at baseline assessment were used as outcomes. Mini Mental Status Examination (MMSE) scores at baseline assessment and at 5-year follow-up assessment were recorded. Age, sex, body mass index, number of medications and educational level were used as covariates. Results: Increased mean value of Stride Time (i.e; worst gait performance) while usual walking was associated with increased delta MMSE (i.e; worst cognitive performance) (P=0.043). Both linear and Cox regressions showed also that increased CoV of Stride Time (i.e; worst gait performance) while performing a verbal fluency task was associated with increased delta MMSE and abnormal MMSE (P≤0.048) but not under the others walking conditions. Conclusions: Increased Stride Time variability while performing a verbal fluency task predicts cognitive decline. These results confirm the strong relationship between gait and cognitive decline, and thus open new perspective in terms of prediction of dementia. Disclosure: Dr. Beauchet has nothing to disclose. Dr. Allali has nothing to disclose.
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Subjective Memory Impairment and Gait Variability in Cognitively Healthy Individuals: Results from a Cross-Sectional Pilot Study.
Journal of Alzheimer's disease : JAD, 2016Co-Authors: Olivier Beauchet, Cyrille P. Launay, Julia Chabot, Elise J. Levinoff, Gilles AllaliAbstract:Increased Stride Time variability has been associated with memory impairment in mild cognitive impairment. Subjective memory impairment (SMI) is considered the earliest clinical stage of Alzheimer's disease (AD). The association between increased Stride Time variability and SMI has not been reported. This study aims to examine the association of Stride Time variability while performing single and dual tasking with SMI in cognitively healthy individuals (CHI). A total of 126 CHI (15 without SMI, 69 with SMI expressed by participants, 10 with SMI expressed by participant's relative, and 32 with SMI expressed by both participants and their relatives) were included in this cross-sectional study. The coefficient of variation (CoV) of Stride Time and walking speed were recorded under usual condition and while counting backwards. Age, gender, body mass index, number of drugs taken daily, use of psychoactive drugs, fear of falling, history of previous falls, and walking speed were used as covariates. The multiple linear regression models showed that greater CoV of Stride Time while counting backwards, but not while single tasking, was associated with a participant's relative SMI (p = 0.038). This study found a specific association between SMI expressed by a participant's relative and a greater CoV of Stride Time (i.e., worse performance) while dual tasking, suggesting that the association between gait variability and memory may be present in the earliest stages of memory impairment. Thus, gait variability under dual-task in individuals with SMI expressed by their relatives can be a potential biomarker of AD.
Nir Giladi - One of the best experts on this subject based on the ideXlab platform.
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treadmill walking as an external pacemaker to improve gait rhythm and stability in parkinson s disease
Movement Disorders, 2005Co-Authors: Silvi Frenkeltoledo, Chava Peretz, Leor Gruendlinger, Talia Herman, Nir Giladi, Jeffrey M HausdorffAbstract:Recent reports suggest that external cueing improves Stride length and gait speed in Parkinson's disease (PD). The purpose of the present study was to examine the influence of treadmill walking on gait variability. The 36 PD patients (Hoehn and Yahr stage 2–2.5) were compared to 30 controls. Subjects walked three Times for 2 minutes each: (1) walking on level ground (unassisted), (2) walking on level ground while using a walker, and (3) walking on a treadmill. Stride Time variability and swing Time variability were significantly increased in the patients compared to the control subjects when walking on level ground with a walker. In both groups, the use of a walking aid did not significantly affect Stride Time variability or swing Time variability, but the treadmill reduced Stride Time variability and swing Time variability in the patients and in the controls. These results indicate that, during treadmill walking, PD subjects are able to walk with a less variable and more stable gait. Because the treadmill walking speed was set to the gait speed on level ground and because this effect was not seen with a walking aid, we suggest that the treadmill may be acting as an external cue to enhance gait rhythmicity and reduce gait variability. © 2005 Movement Disorder Society
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Effect of gait speed on gait rhythmicity in Parkinson's disease: variability of Stride Time and swing Time respond differently
Journal of NeuroEngineering and Rehabilitation, 2005Co-Authors: Silvi Frenkel-toledo, Chava Peretz, Leor Gruendlinger, Talia Herman, Nir Giladi, Jeffrey M HausdorffAbstract:Background The ability to maintain a steady gait rhythm is impaired in patients with Parkinson's disease (PD). This aspect of locomotor dyscontrol, which likely reflects impaired automaticity in PD, can be quantified by measuring the Stride-to-Stride variability of gait timing. Previous work has shown an increase in both the variability of the Stride Time and swing Time in PD, but the origins of these changes are not fully understood. Patients with PD also generally walk with a reduced gait speed, a potential confounder of the observed changes in variability. The purpose of the present study was to examine the relationship between walking speed and gait variability. Methods Stride Time variability and swing Time variability were measured in 36 patients with PD (Hoehn and Yahr stage 2–2.5) and 30 healthy controls who walked on a treadmill at four different speeds: 1) Comfortable walking speed (CWS), 2) 80% of CWS 3) 90% of CWS, and 4) 110% of CWS. In addition, we studied the effects of walking slowly on level ground, both with and without a walker. Results Consistent with previous findings, increased variability of Stride Time and swing Time was observed in the patients with PD in CWS, compared to controls. In both groups, there was a small but significant association between treadmill gait speed and Stride Time variability such that higher speeds were associated with lower (better) values of Stride Time variability (p = 0.0002). In contrast, swing Time variability did not change in response to changes in gait speed. Similar results were observed with walking on level ground. Conclusion The present results demonstrate that swing Time variability is independent of gait speed, at least over the range studied, and therefore, that it may be used as a speed-independent marker of rhythmicity and gait steadiness. Since walking speed did not affect Stride Time variability and swing Time variability in the same way, it appears that these two aspects of gait rhythmicity are not entirely controlled by the same mechanisms. The present findings also suggest that the increased gait variability in PD is disease-related, and not simply a consequence of bradykinesia.
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Effect of gait speed on gait rhythmicity in Parkinson's disease: variability of Stride Time and swing Time respond differently
Journal of neuroengineering and rehabilitation, 2005Co-Authors: Silvi Frenkel-toledo, Chava Peretz, Leor Gruendlinger, Talia Herman, Nir Giladi, Jeffrey M HausdorffAbstract:Background: The ability to maintain a steady gait rhythm is impaired in patients with Parkinson's disease (PD). This aspect of locomotor dyscontrol, which likely reflects impaired automaticity in PD, can be quantified by measuring the Stride-to-Stride variability of gait timing. Previous work has shown an increase in both the variability of the Stride Time and swing Time in PD, but the origins of these changes are not fully understood. Patients with PD also generally walk with a reduced gait speed, a potential confounder of the observed changes in variability. The purpose of the present study was to examine the relationship between walking speed and gait variability. Methods: Stride Time variability and swing Time variability were measured in 36 patients with PD (Hoehn and Yahr stage 2–2.5) and 30 healthy controls who walked on a treadmill at four different speeds: 1) Comfortable walking speed (CWS), 2) 80% of CWS 3) 90% of CWS, and 4) 110% of CWS. In addition, we studied the effects of walking slowly on level ground, both with and without a walker. Results: Consistent with previous findings, increased variability of Stride Time and swing Time was observed in the patients with PD in CWS, compared to controls. In both groups, there was a small but significant association between treadmill gait speed and Stride Time variability such that higher speeds were associated with lower (better) values of Stride Time variability (p = 0.0002). In contrast, swing Time variability did not change in response to changes in gait speed. Similar results were observed with walking on level ground. Conclusion: The present results demonstrate that swing Time variability is independent of gait speed, at least over the range studied, and therefore, that it may be used as a speed-independent marker of rhythmicity and gait steadiness. Since walking speed did not affect Stride Time variability and swing Time variability in the same way, it appears that these two aspects of gait rhythmicity are not entirely controlled by the same mechanisms. The present findings also suggest that the increased gait variability in PD is
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Walking is more like catching than tapping: gait in the elderly as a complex cognitive task
Experimental Brain Research, 2005Co-Authors: Jeffrey M Hausdorff, Galit Yogev, Shmuel Springer, Ely S. Simon, Nir GiladiAbstract:Walking is generally viewed as an automated, over-learned, rhythmic motor task and may even be considered the lower-limb analog of rhythmic finger tapping, another automated motor task. Thus, one might hypothesize that walking would be associated with a simple rhythmic task like tapping rather than with a complex motor task like catching. Surprisingly, however, we find that among older adults, routine walking has more in common with complex motor tasks, like catching a moving object, than it does with tapping. Tapping performance, including both the average tapping interval and the variability of tapping interval, was not significantly associated with any gait parameter (gait speed, average Stride Time and Stride Time variability). In contrast, catch game performance was significantly associated with measures of walking, suggesting that walking is more like catching than it is like tapping. For example, participants with a higher gait speed tended to have lower Times to first move when catching, better catching accuracy, and less catching errors. Stride Time variability was significantly associated with each of the measures of catching. Participants with a lower Stride Time variability (a more steady gait) had better catching accuracy, lower Time to first move, fewer direction changes when moving the cursor to catch the falling object, and less catching errors. To understand this association, we compared walking performance to performance on the Stroop test, a classic measure of executive function, and tests of memory. Walking was associated with higher-level cognitive resources, specifically, executive function, but not with memory or cognitive function in general. For example, a lower (better) Stride Time variability was significantly associated with higher (better) scores on the Stroop test, but not with tests of memory. Similarly, when participants were stratified based on their performance on the Stroop test and tests of memory, Stride Time variability was dependent on the former, but not the latter. These findings underscore the interconnectedness of gait and cognitive function, indicate that even routine walking is a complex cognitive task that is associated with higher-level cognitive function, and suggest an alternative approach to the treatment of gait and fall risk in the elderly.
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Gait dynamics in Parkinson's disease: relationship to Parkinsonian features, falls and response to levodopa.
Journal of the neurological sciences, 2003Co-Authors: Joanna D. Schaafsma, Nir Giladi, Yacov Balash, Anna L. Bartels, Tanya Gurevich, Jeffrey M HausdorffAbstract:Patients with Parkinson's disease (PD) have an increased risk of falling that has yet to be fully explained. To better understand the gait disturbance in PD and the factors that contribute to falls, we quantitatively evaluated: (1) the relationship between gait variability (a marker of fall risk in other populations), fall history, and other parkinsonian features, and (2) the effects of levodopa on these relationships. The average Stride Time and Stride-to-Stride variability were measured using force-sensitive insoles during comfortable walking. Fall frequency, motor control, function, and mental health were measured using the Unified Parkinson's Disease Rating Scale (UPDRS), the Mini-Mental State Exam (MMSE), and the Timed motor tests of the Core Assessment Program for Intracerebral Transplantations (CAPIT) in 32 subjects with idiopathic PD, in an "off" (unmedicated) state and again in an "on" (medicated) state. Average Stride Time was not associated with any UPDRS or CAPIT measure and was similar in fallers and non-fallers in "off" and "on" states (p>0.27). Stride Time variability was significantly associated with fall frequency as well as with total scores on the CAPIT and the UPDRS, ADL abilities, and motor function. Stride Time variability and falls were not related to tremor, rigidity or bradykinesia in the "off" state. 41% of subjects reported one or more falls. Stride Time variability was 8.8+/-7.9% in fallers and 4.2+/-1.3% in non-fallers (p<0.009). Stride Time variability significantly improved in response to levodopa, both in fallers and non-fallers, but remained increased in fallers (vs. non-fallers). The patho-physiology responsible for impaired Stride-to-Stride regulation of gait timing is apparently independent of other cardinal features of PD, i.e., tremor, rigidity, or bradykinesia, but is responsive to levodopa. Stride-to-Stride variability is especially impaired among PD subjects with a history of falls, suggesting, for the first Time, the possibility of exaggerated impairment of internal clock function in PD fallers.
Cédric Annweiler - One of the best experts on this subject based on the ideXlab platform.
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Anti-dementia drugs-related changes in gait performance while single and dual tasking in patients with Alzheimer disease: a meta-analysis.
Current Alzheimer research, 2015Co-Authors: Olivier Beauchet, Manuel Montero-odasso, Cédric Annweiler, Cyrille P. Launay, Gilles AllaliAbstract:BACKGROUND: The effects of anti-dementia drugs on gait performance in Alzheimer disease (AD) are questionable. The objective of this meta-analysis was to examine the effects of anti-dementia drugs on the mean value and the coefficient of variation (CoV) of Stride Time among patients with AD while taking into account the type of drugs (i.e., acetylcholinesterase inhibitors [AChEIs] versus memantine) and the walking conditions (i.e., single versus dual-task). METHODS: An English and French Medline search was conducted in March 2015, with no limit of date, using the Medical Subject Headings terms "pharmaceutical preparations" combined with terms "Pharmaceutical preparations" OR "Therapeutic uses" OR "Drug substitution" OR "Drugs essential" OR "Drugs, Generic" OR "Psychotropic drugs" combined with "Delirium" OR "Dementia" OR "Amnestic" OR "Cognitive disorders" AND "Gait" OR "Gait Ataxia" OR "Gait disorders, Neurologic" OR "Gait apraxia". Fixed-effects meta-analyses were used to examine anti-dementia drugs-related changes in mean value and CoV of Stride Time. RESULTS: Of the 66 identified abstracts, 5 (7.6%) were included in the meta-analysis. Inter-group comparison of between-visit change underscored a significant decrease in CoV of Stride Time (P0.06). Intra-group changes in Stride Time parameters following the use of anti-dementia drugs showed a significant decrease for memantine (PCONCLUSIONS: Anti-dementia drugs demonstrated a significant improvement of gait performance with specific class effect depending on the walking conditions and on the type of Stride Time parameters considered. Language: en
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Episodic memory and executive function impairments in non-demented older adults: which are the respective and combined effects on gait performances?
Age (Dordrecht Netherlands), 2015Co-Authors: Olivier Beauchet, Cédric Annweiler, Cyrille P. Launay, Bruno Fantino, Gilles AllaliAbstract:Gait control depends in part on cognition. This study aims to examine the separate and combined effects of episodic memory and executive function impairments on the mean value and the coefficient of variation (CoV) of Stride Time among non-demented older community dwellers. Based on a cross-sectional design, 1458 older community dwellers without dementia (70.6 ± 4.9 years; 49.2 % female) were recruited and separated into cognitively healthy individuals (CHI) and individuals with cognitive impairment. A score ≤5/6 on the Short Mini-Mental State Examination defined episodic memory impairment. Impaired executive function was defined by errors on the clock-drawing test. Mean value and CoV of Stride Time were measured by the GAITRite® system. A total of 517 participants (35.5 %) had cognitive impairment in at least one cognitive domain. Participants with memory impairment (P = 0.006) and those with combined cognitive impairments (P < 0.001) had greater (i.e., worse gait performance) mean value of Stride Time (P = 0.006) compared to CHI. Participants with combined cognitive impairment had a greater CoV of Stride Time (i.e., worse gait performance) compared to CHI (P = 0.004) and to those with separate memory impairment (P = 0.037). Among participants with combined cognitive impairments, mean value and CoV of Stride Time had the highest effect size (respectively, effect size = 0.49 [95 % confidence interval (CI) 0.27;0.71] and effect size = 0.40 [95 %CI 0.18;0.62]). Participants with episodic memory or executive impairments had a greater mean value and CoV of Stride Time compared to those with no cognitive impairment. Combined episodic memory and executive impairments exceeded the sum of separate impairments on gait performances, suggesting a complex interplay going beyond a simple additive effect.
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Association between gait variability and brain ventricle attributes: a brain mapping study.
Experimental gerontology, 2014Co-Authors: Cédric Annweiler, Manuel Montero-odasso, Robert Bartha, John Drozd, Vladimir Hachinski, Olivier BeauchetAbstract:Abstract Background It remains unknown which brain regions are involved in the maintenance of gait dynamic stability in older adults, as characterized by a low Stride Time variability. Expansion of lateral cerebral ventricles is an indirect marker of adjacent brain tissue volume. The purpose of this study was to examine the association between Stride Time variability and the volume of sub-regions of the lateral cerebral ventricles among older community-dwellers. Methods One-hundred-fifteen participants free of hydrocephalus from the GAIT study (mean, 70.4 ± 4.4 years; 43.5% female) were included in this analysis. Stride Time variability was measured at self-selected pace with a 10 m electronic portable walkway (GAITRite). Participants were separated into 3 groups based on tertiles of Stride Time variability (i.e., 2.8%). Brain ventricle sub-volumes were quantified from three-dimensional T 1 -weighted MRI using semi-automated software. Age, gender, Cumulative Illness Rating Scale for Geriatrics, Mini-Mental State Examination, Go-NoGo, brain vascular burden, 4-item Geriatric Depression Scale, psychoactive drugs, vision, proprioception, body mass index, muscular strength and gait velocity were used as covariates. Results Participants with the highest (i.e., worst) tertile of Stride Time variability exhibited larger temporal horns than those with the lowest (P = 0.030) and intermediate tertiles (P = 0.028). They also had larger middle portions of ventricular bodies than those with the intermediate tertile (P = 0.018). Larger temporal horns were associated with increase in Stride Time variability (adjusted β = 0.86, P = 0.005), specifically with the highest tertile of Stride Time variability (adjusted OR = 2.45, P = 0.044). Conclusions Higher Stride Time variability was associated with larger temporal horns in older community-dwellers. Addressing focal neuronal losses in temporal lobes may represent an important strategy to prevent gait instability.
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Physical training-related changes in gait variability while single and dual tasking in older adults: magnitude of gait variability at baseline matters.
European journal of physical and rehabilitation medicine, 2013Co-Authors: Olivier Beauchet, Gilles Allali, Cédric Annweiler, Cyrille P. Launay, Bruno Fantino, De Decker LAbstract:OBJECTIVES Few studies have examined the effects of physical training programs on gait variability while single and dual tasking, and they reported mixed results. The aim of this study was to compare the Stride Time variability while single and dual tasking before and after a physical training program developed to improve gait stability in French community-dwelling older adults. DESIGN A prospective pre-post interventional cohort study. SETTING The community-dwelling area of "Pays de la Loire", France. POPULATION Forty-eight older adults (mean age ± standard deviation 72.2±8 years; 75% female). METHODS Physical training program consisted in 12 sessions scheduled to attend physical exercises 1 Time a week with total Time duration of 3 months. Coefficient of variation (CoV) of Stride Time under three walking conditions (i.e., walking alone, walking while backward counting, and while performing a verbal fluency task) was determined while steady-state walking using the SMTEC® footswitches system before and after the physical training program. Participants were separated into two groups based on being or not in the highest tertile (i.e., worst performance with cutpoint >4.4%) of the CoV of Stride Time while walking alone. RESULTS After physical training compared to before period, a significant decrease in CoV of Stride Time (i.e., better gait performance) while walking alone (2.8±2.8% versus 7±7.1%, P=0.001) but not while dual tasking (P=0.600 for counting backward and P=0.105 for verbal fluency task) was shown in participants who had highest (i.e., worst) gait variability at baseline. In addition, physical training modified the strategy of dual tasking in participants with highest gait variability at baseline compared to the other participants. Before training, a significant decrease in CoV of Stride Time (7±7.1% versus 4.9±4.6%, P=0.017) while counting backward was shown, but there was a significant increase after training (2.8±2.8% versus 5.4±5.8%, P=0.007). CONCLUSIONS Physical training reduced gait variability while walking alone in participants with gait instability, and influenced their strategy for dual tasking. CLINICAL REHABILITATION IMPACT Physical program training developed in the community to improve gait stability should included participants with high gait variability.
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Anti-dementia drugs and changes in gait: a pre-post quasi-experimental pilot study
BMC neurology, 2013Co-Authors: Olivier Beauchet, François Herrmann, Cyrille P. Launay, Gazan Allali, Gilles Watfa, Karim Gallouj, Cédric AnnweilerAbstract:Anti-dementia drugs may improve gait performance. No comparison between acetylcholinesterase inhibitors (CEIs) and memantine-related changes in gait variability has been reported. The objectives of this study were to 1) quantify and compare the mean values and coefficients of variation (CoV) of Stride Time in demented patients with Alzheimer’s disease and related disorders (ADRD) before and after the use of CEIs or memantine, and in age- and gender-matched controls patients with ADRD using no anti-dementia drugs; and 2) to determine whether changes in CoV of Stride Time differed between CEIs or memantine. A total of 120 demented patients with mild-to-moderate ADRD were prospectively included in this pre-post quasi-experimental study with two intervention groups (43 patients taking CEIs, and 41 taking memantine) and a control group (36 age- and gender matched patients without any anti-dementia drugs). CoV of Stride Time and walking speed were measured with GAITRite® system while usual walking at steady state. Age, gender, number of drugs daily taken, use of psychoactive drugs, body mass index and Time between the two visits were also recorded. There was no difference between groups for the Time between baseline and follow-up assessments (232.9 ± 103.7 days for patients without anti-dementia drugs, 220.0 ± 67.5 days for patients with CEIs, 186.7 ± 96.2 days for patients with memantine, P = 0.062). Patients with memantine had a lower (i.e., better) CoV of Stride Time at follow-up assessment compared to those with CEIs (4.2 ± 2.4% versus 5.8 ± 4.2%, P = 0.010). Patients with memantine had a greater decrease in CoV of Stride Time compared to those with CEIs (−1.90% versus 0.93%, P = 0.010) and mixed-effects linear regressions showed that this decrease was specifically explained by memantine (P = 0.028). Our results showed that patients with ADRD and treated with memantine, but not those with CEIs, decreased their gait variability, and thus improved their gait safety (Trial registration number: NCT01315704 ).
