Gait analysis in demented subjects: Interests and perspectives

Gait disorders are more prevalent in dementia than in normal aging and are related to the severity of cognitive decline. Dementia-related gait changes (DRGC) mainly include decrease in walking speed provoked by a decrease in stride length and an increase in support phase. More recently, dual-task related changes in gait were found in Alzheimer’s disease (AD) and non-Alzheimer dementia, even at an early stage. An increase in stride-to-stride variability while usual walking and dual-tasking has been shown to be more specific and sensitive than any change in mean value in subjects with dementia. Those data show that DRGC are not only associated to motor disorders but also to problem with central processing of information and highlight that dysfunction of temporal and frontal lobe may in part explain gait impairment among demented subjects. Gait assessment, and more particularly dual-task analysis, is therefore crucial in early diagnosis of dementia and/or related syndromes in the elderly. Moreover, dual-task disturbances could be a specific marker of falling at a pre-dementia stage

Hippocampal volume, early cognitive decline and gait variability: Which association?

BACKGROUND: In contrast to its prominent function in cognition, the involvement of the hippocampus in gait control is still a matter of debate. The present study aimed to examine the association of the hippocampal volume with mean values and coefficients of variation (CoV) of spatio-temporal gait parameters among cognitively healthy individuals (CHI) and patients with mild cognitive impairment (MCI). METHODS: A total of 90 individuals (47 CHI with a mean age of 69.7±3.6years and 48.9% women, and 43 MCI individuals with a mean age of 70.2±3.7years and 62.8% women) were included in this cross-sectional study. The hippocampal volume was quantified from a three-dimensional T1-weighted MRI using semi-automated software. Mean values and CoV of stride time, swing time and stride width were measured at self-selected pace with a 10m electronic portable walkway (GAITRite®). Age, gender, body mass index, number of drugs daily taken, Mini-Mental State Examination (MMSE) score, history of falls, walking speed and white matter signal-intensity abnormality scoring with Manolio scale were used as covariates. RESULTS: Patients with MCI had a lower MMSE score (P0.650). CONCLUSIONS: Our findings revealed a positive association between a greater (i.e., better morphological structure) hippocampal volume and a greater (i.e., worse performance) stride time variability among CHI, but not among MCI individuals

Respective and combined effects of impairments in sensorimotor systems and cognition on gait performance: a population-based cross-sectional study.

BACKGROUND: Respective and combined effects of impairments in sensorimotor systems and cognition on gait performance have not been fully studied. This study aims to describe the respective effects of impairments in muscle strength, distance vision, lower-limb proprioception and cognition on the Timed Up & Go (TUG) scores (i.e., performed TUG [pTUG], imagined TUG [iTUG] and the time difference between these two tests [delta TUG]) in older community-dwellers; and to examine their combined effects on TUG scores. METHODS: Based on a cross-sectional design, 1792 community-dwellers (70.2±4.8 years; 53.6% female) were recruited. Gait performance was assessed using pTUG, iTUG and delta TUG. Participants were divided into healthy individuals and 15 subgroups of individuals according to the presence of impairment in one or more subsystems involved in gait control (i.e., muscle strength and/or distance vision and/or lower-limb proprioception and/or cognition [episodic memory and executive performance]). Impairment in muscle strength, distance vision and lower-limb proprioception was defined as being in the lowest tertile of performance. Impairment in cognition was defined as abnormal episodic memory and executive tests. RESULTS: A total of 191 (10.7%) exhibited impairment in muscle strength, 188 (10.5%) in distance vision, 302 (16.9%) in lower-limb proprioception, and 42 (2.3%) in cognition. Linear regressions showed that cognitive impairment as well as dual combinations of impairments were associated with increased pTUG (P CONCLUSION: Cognitive integrity is central for efficient gait control and stability, whereas lower-limb proprioception seems to be central for gait imagery

Association between dual task-related decrease in walking speed and real versus imagined Timed Up and Go test performance

Background and aims: To examine whether older people with markedly dual task-related decreases in walking speed—a marker of disturbed higher-level gait control and falls—have a larger discrepancy between real and imagined Timed Up and Go (TUG) test times than those with less dual task-related decreases in walking speed. Methods: Based on a prospective cross-sectional study, 193 older adults (mean age 77.4±5.9years; 44.0% women) referred to and consecutively assessed at a Swiss university clinic for a gait analysis to assess either gait disorders, fall risk or memory disorders were included. For all participants, walking speed was measured using a GAITRite® electronic walkway system during usual walking at self-selected pace and while dual tasking (i.e., usual walking and simultaneously counting backwards out loud). In addition, real Timed Up and Go (TUGr) and imagined Timed Up and Go (TUGi) (i.e., the time needed to imagine performing the TUGr) times were measured with a stopwatch. Differences between both walking conditionsfor walking speed (delta of walking speed) and both TUG conditions (delta of TUG time) were calculated. Age, gender, height, total number drugs taken per day, daily use of psychoactive drugs, use of walking aid, history of falls, Mini-Mental State Examination score, near vision and education level were used as covariables in this analysis. Results: Participants were categorized into two groups based on being in the lowest tertian (i.e., <33%: group A corresponding to participants undisturbed by dual task) or not (i.e., ≥33%: group B corresponding to participants disturbed by dual task) of the delta of walking speed. In both groups, TUGr and TUGi times were similar (P=.169 and P=.839). In both groups, TUGi was faster than TUGr (P<.001). Delta of TUG time was significantly greater in group B compared to group A (P<.001). After adjustment for all covariables, only the delta of walking speed was significantly associated with the delta of TUG time (P=<.001). Stepwise backward regression showed that polypharmacy (P=.017) and delta of walking speed (P=<.001) were associated with an increase in delta of TUG time, whereas an increased MMSE score (P=.030) was associated with a decrease in delta of TUG time. Conclusion: These findings show that a large discrepancy between real and imagined TUG performances is significantly correlated with a decrease in walking speed while dual tasking, and thus may also be a surrogate marker of disturbed higher-level gait control. The quickly and easily performed TUG tests may represent a feasible, practical screening tool for early detection of higher-level gait disorders in older adult

Dual-task related gait changes after CSF tapping: a new way to identify idiopathic normal pressure hydrocephalus

BACKGROUND: Gait disturbances found in patients with idiopathic normal pressure hydrocephalus (iNPH) are unspecific to the diagnosis and commonly occur in neurodegenerative or vascular conditions (iNPH-like conditions). This current retrospective pre-post intervention study aims to determine whether changes in quantitative gait parameters during dual task condition differed between iNPH and iNPH-like conditions before and after cerebrospinal fluid (CSF) tapping. METHODS: 49 patients assessed before and after CSF tapping were included in this study (27 with iNPH and 22 with iNPH-like conditions). Gait analysis during single and dual task conditions (walking and backward counting) was performed before and after a CSF spinal tap of 40 ml. Gait parameters were compared between iNPH and iNPH-like conditions patients. Logistic regressions were used to examine the association between iNPH and gait parameters. RESULTS: Improvements of step width (−9.03 (20.75)% for iNPH group; +0.28 (21.76)% for iNPH-like conditions group), stride length (+7.82 (20.71)% for iNPH group; -0.62 (19.22)% for iNPH-like conditions group), walking speed (+12.20 (29.79)% for iNPH group; +2.38 (32.50)% for iNPH-like conditions group) and stance duration (−1.23 (4.03)% for iNPH group; +0.49 (5.12)% for iNPH-like conditions group) during dual task, after CSF spinal tapping, were significant in patients with iNPH compared to patients with iNPH-like conditions. No between group difference was observed for the single walking task evaluation. The multiple logistic regression revealed that among these four gait parameters, only the improvement in step width was associated with the diagnosis of iNPH. CONCLUSION: Dual-task related changes in spatio-temporal gait parameters before and after CSF tapping might be a novel and discriminative method of identifying iNPH patients from other similar conditions

‘Faster counting while walking' as a predictor of falls in older adults

Objective: to establish whether changes in a spoken verbal task performance while walking compared with being at rest could predict falls among older adults. Design: prospective cohort study of 12 months' duration. Setting: twenty-seven senior housing facilities. Participants: sample of 187 subjects aged 75-100 (mean age 84.8±5.2). During enrollment, participants were asked to count aloud backward from 50, both at rest and while walking and were divided into two groups according to their counting performance. Information on incident falls during the follow-up year was monthly collected. Measurements: the number of enumerated figures while sitting on a chair and while walking, and the first fall that occurred during the follow up year. Results: the number of enumerated figures under dual-task as compared to single task increased among 31.5% of the tested subjects (n=59) and was associated with lower scores in MMSE (P=0.034), and higher scores in Geriatric Depression Scale (P=0.007) and Timed Up & Go (P=0.005). During the 12 months follow-up, 54 subjects (28.9%) fell. After adjusting for these variables, the increase in counting performance was significantly associated with falls (adjusted OR = 53.3, P < 0.0001). Kaplan-Meier distributions of falls differed significantly between subjects who either increased or decreased their counting performance (P < 0.0001). Conclusions: faster counting while walking was strongly associated with falls, suggesting that better performance in an additional verbal counting task while walking might represent a new way to predict falls among older adult

Gait control: a specific subdomain of executive function?

<p>Abstract</p> <p>Background</p> <p>Few studies looked at the association between gait variability and executive subdomains (ESD). The aim of this study was to examine the association between ESD (i.e., information updating and monitoring) and stride time variability among healthy older adults.</p> <p>Methods</p> <p>Seventy-eight healthy older adults (mean age 69.9 ± 0.9 years, 59% women) were divided into 3 groups according to stride time variability (STV) tertiles while steady state walking. Coefficient of variation of stride time was used as a marker of STV. Scores on cognitive tests evaluating information updating and monitoring (Digit Span test), mental shifting (Trail Making Test part A and part B) and cognitive inhibition (Stroop Color Word test) were used as measures of ESD.</p> <p>Results</p> <p>The full adjusted and the stepwise backward logistic regression models showed that the highest tertile (i.e., the worst performance) of STV was only associated with lower Digit Span performance (Odds ratio = 0.78 with P = 0.020 and Odds ratio = 0.81 with P = 0.019).</p> <p>Conclusions</p> <p>Information updating and monitoring are associated with STV in the sample of studied participants, suggesting that walking may be a complex motor task depending specifically of this subdomain of executive functions.</p

Functional mobility in older women with and without motoric cognitive risk syndrome: a quantitative assessment using wearable inertial sensors

Background. The Motoric Cognitive Risk (MCR) syndrome is defined in non-demented older adults by cognitive complaints and slow gait. Individuals with MCR are at higher risk of dementia and other poor clinical outcomes, such as falls. However, no data are available as regards functional mobility alterations associated with MCR. The main purpose of the present study is to quantitatively investigate such an aspect using the instrumented Timed-Up-and-Go (iTUG) test carried out using a wearable inertial measurement unit (IMU). Methods. Fifty-one women aged over 65 years underwent a geriatric and neuropsychologic assessment (which included the Mini Mental State Examination, MMSE and Addenbrooke’s Cognitive Examination Revised, ACE-R), instrumented gait analysis and iTUG performed using an IMU located on the lower back. Based on subjective cognitive complaints and slow gait, they were assigned either to the MCR (n = 24) or non-MCR (n = 27) group. IMU data allowed calculation of overall and sub-phases iTUG times. Results. Women with MCR were characterized by a significantly higher body mass and body mass index, lower normalized handgrip strength, and similar values of MMSE compared to non-MCRs. A trend was observed in terms of lower overall and sub-domain ACE-R score. They also performed iTUG at a significantly slower speed (22.4 s vs 14.1 of the non-MCR group, p &lt; 0.001) and exhibited increased sub-phase times (29 to 31% higher with respect to non-MCRs). Conclusions. The findings of the present study suggest that the MCR syndrome impairs functional mobility, probably due reduced muscular strength and coordination, fear of falling and increased instability. The instrumental evaluation of functional mobility appears useful in the management of women with MCR, particularly in monitoring the progression of the motor impairments, verifying the effectiveness of interventions targeted in alleviating the impact on daily life of mobility limitations associated with MCR and in defining tailored rehabilitation programs

Test-retest reliability of stride time variability while dual tasking in healthy and demented adults with frontotemporal degeneration

Although test-retest reliability of mean values of spatio-temporal gait parameters has been assessed for reliability while walking alone (i.e., single tasking), little is known about the test-retest reliability of stride time variability (STV) while performing an attention demanding-task (i.e., dual tasking). The objective of this study was to examine immediate test-retest reliability of STV while single and dual tasking in cognitively healthy older individuals (CHI) and in demented patients with frontotemporal degeneration (FTD)