Gait Function in Adults Aged 50 Years and Older With Spina Bifida.

OBJECTIVE: To study gait function among individuals with spina bifida (SB) aged 50 years or older. DESIGN: A cross-sectional study conducted in 2017. SETTING: Home-dwelling participants from all regions in Norway. PARTICIPANTS: Individuals between the ages of 51 and 76 years (N=26; 16 women) categorized as independent walkers (n=9), walkers with aids (n=10) and nonwalkers (n=7). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Questionnaire, pain assessment, anthropometry, Falls Efficacy Scale International (FES-I), objective gait analysis, 6-minute walk test (6MWT), and timed Up and Go (TUG). RESULTS: Walking speed correlated with SB severity (ρ=-.59; P=.008). Individuals who walked slower than 0.81 m/s had a higher body mass index (BMI) than those who walked faster (P=.008). Independent walkers walked slower than healthy age-matched walkers (P=.046); spatiotemporal variables showed that this was owing to shorter steps rather than cadence. The mean TUG was 10.6±2.6 seconds in independent walkers and 20.2±6.5 in walkers with aids (P<.01). The mean 6MWT was 504±126 meters in independent walkers and 316±88 in walkers with aids (P<.01). The mean pain intensity (numeric rating scale) was 4.9±2.2 in independent walkers and 4.2±1.6 in walkers with aids, but the difference was not statistically significant. FES-I was significantly lower among independent walkers (mean, 23.6±3.9) than walkers with aids (mean, 31.4±10.0) (P=.042). CONCLUSIONS: Participants commonly experienced an early onset deterioration in gait function, and walking speed was influenced by SB severity and BMI. This highlights the importance of early monitoring and weight management during follow-up for SB.

Highly challenging balance and gait training for individuals with Parkinson's disease improves pace, rhythm and variability domains of gait - A secondary analysis from a randomized controlled trial.

OBJECTIVE: Evaluate immediate and long-term effects of highly challenging balance and gait training on pace-, rhythm-, variability-, asymmetry-, and postural control domains of gait for individuals with Parkinson's disease (PD). DESIGN: Randomized controlled trial - a secondary analysis. SETTING: University hospital setting. PARTICIPANTS: One-hundred older adults with mild to moderate PD (Hoehn & Yahr 2 and 3). INTERVENTION: Training group (n = 51): 10 weeks (3 times/week) of intensive balance and gait training, incorporating dual tasks. Control group (n = 49): care as usual. MAIN OUTCOME MEASURES: Spatiotemporal gait variables collected during normal and fast walking on a pressure-sensitive mat. A linear mixed model was used to evaluate training effects post intervention and at the 6 and 12 month follow-up. RESULTS: Immediate training effects in the pace domain of gait were increased step velocity (normal speed: 8.2 cm/s, P = 0.04; fast: 10.8 cm/s, P < 0.01), increased step length (normal speed: 3 cm, P = 0.05; fast: 2.3 cm, P = 0.05) and reduced swing time variability (fast speed: -2.5 ms, P = 0.02). In the rhythm domain reduced step time (fast speed: -19.3 ms, P = 0.02), stance time (normal: -24.3 ms, P = 0.01; fast: -29.6 ms, P = 0.02) and swing time (fast speed: -8.7 ms, P = 0.04) was seen. Relative to the variability domain, the training decreased step time variability (fast: -2.8 ms, P = 0.02) and stance time variability (fast: -3.9 ms, P = 0.02). No training effects were retained at 6 months. CONCLUSIONS: Highly challenging balance and gait training improved pace, rhythm and variability aspects of PD gait in the short-term, but effects are not retained long-term. TRIAL REGISTRATION NUMBER: NCT01417598.

Dual-Task Effects During a Motor-Cognitive Task in Parkinson's Disease: Patterns of Prioritization and the Influence of Cognitive Status.

People with Parkinson's disease (PD) experience greater difficulties during dual task (DT) walking compared to healthy controls, but factors explaining the variance in DT costs remain largely unknown. Additionally, as cognitive impairments are common in PD it is important to understand whether cognitive status influences the strategies used during DT paradigms. The study aimed to (1) explore DT costs on gait and cognition during DT walking, (2) investigate factors associated with DT costs, and (3) to investigate to what extent patterns of DT costs and prioritization differed according to cognitive status. A total of 93 people with Parkinson's disease were examined when walking in single and DT conditions. Information regarding demographics, PD severity, mobility, and cognitive and affective symptoms was collected, and an extensive neuropsychological test battery was used to classify whether participants had mild cognitive impairment (PD MCI) or not (PD non-MCI). Dual task costs were observed across all gait domains except asymmetry. Cognitive status was associated with DT costs on both gait and cognition. Nonmotor experiences of daily living were further associated with DT cost on cognition, and TUG-cog associated with DT cost on gait. People with PD MCI had larger DT costs on gait than PD non-MCI. Strategies differed according to cognitive status, whereby PD MCI used a posture-second strategy, and PD non-MCI used a posture-first strategy. Once verified in future studies, these results can inform clinicians and researchers when tailoring DT training paradigms to the specific characteristics of people with PD.

The effects of integrated single- and dual-task training on automaticity and attention allocation in Parkinson's disease: A secondary analysis from a randomized trial.

OBJECTIVE: People with Parkinson's disease (PwPD) demonstrate impaired automaticity of motor and cognitive tasks, with unclear prioritization strategies when exposed to dual-task situations. However, no randomized trials have investigated the effects of training on automaticity and prioritization strategies in this population. The purpose of this study was to investigate the effects of training on the automaticity of gait and cognitive processing in PwPD and the allocation of attention between gait and a cognitive task. METHOD: One-hundred PwPD were randomized to 10 weeks of challenging gait and balance training (including single and dual-task conditions) or to a control group (care as usual). Outcome measure was the absolute dual-task interference (difference between single- and dual-tasks) for gait and cognitive parameters. Differences between baseline and follow-up were compared between the groups. The Mann-Whitney U test was used to assess potential differences. Significance level was set to p = .05. The direction and magnitude of nonparametric effect sizes were used to investigate attention allocation. RESULTS: No significant between-groups differences were found regarding any gait parameter. The training group significantly improved the dual-task interference of the cognitive task. The direction of between-groups effect sizes indicated that the training group primarily allocated attention to the cognitive task, whereas the control group appeared to prioritize gait. CONCLUSIONS: The results indicate that challenging training can improve automaticity of cognitive processing during walking. This may have a beneficiary effect on the ability to ambulate safely in the community, thereby improving independence and the quality of life in this population. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Addressing limitations of the Gait Variability Index to enhance its applicability: The enhanced GVI (EGVI).

Prior research has established the Gait Variability Index (GVI) as a composite measure of gait variability, based on spatiotemporal parameters, that is associated with functional outcomes. However, under certain circumstances the magnitude and directional specificity of the GVI is adversely affected by shortcomings in the calculation method. Here we present an enhanced gait variability index (EGVI) that addresses those shortcomings and improves the utility of the measure. The EGVI was further enhanced by removing some input spatiotemporal variables that captured overlapping/redundant information. The EGVI was used to reanalyze data from four previously published studies that used the original GVI. After removing data affected by the GVI's prior shortcomings, the association between EGVI and GVI values was stronger for the pooled dataset (r2 = 0.95) and for the individual studies (r2 = 0.88-0.98). The EGVI also revealed stronger associations between the index value and functional outcomes for some studies. The EGVI successfully addresses shortcomings in the GVI calculation that affected magnitude and directional specificity of the index. We have confirmed the validity of prior published work that used the original GVI, while also demonstrating even stronger results when these prior data were re-analyzed with the EGVI. We recommend that future research should use the EGVI as a composite measure of gait variability.

The reliability of gait variability measures for individuals with Parkinson's disease and healthy older adults - The effect of gait speed.

BACKGROUND: Step-to-step variability is a marker of reduced motor control and a frequently studied outcome measure in neurodegenerative disorders such as Parkinson's disease (PD) as compared to healthy older adults (HOA). To challenge motor control of gait, walking should be tested at different gait speeds. Good reliability is essential, and gait variability estimates show good reproducibility when sampled at normal gait speed. The aim was therefore to investigate if gait variability could be reliably sampled at slow and fast speeds for individuals with PD and HOA by evaluating test-retest reliability. METHODS: 29 (14 males) subjects with idiopathic PD, Hoehn &Yahr 2 (n = 18) and 3, ≥ 60 years, and 25 age matched HOAwere included. Spatiotemporal gait data was collected (GAITRite) during slow, normal, and fast walking on two occasions. RESULTS: Measurement error was lowest for gait variability estimates based on 40 steps in both groups. This was true across all speeds in HOA, but only for normal and fast gait speeds in the PD cohort. Due to increased homogeneity in the variability estimates intraclass correlation coefficients (ICC) were low for HOA, except for step width variability. In the PD cohort ICCs were good to excellent for temporal- and step width gait variability across speeds. CONCLUSION: HOA demonstrated reliable gait variability estimates across all speeds, whereas Individuals with PD were reliable at normal and fast gait speeds only Estimates should be based on at least 40 steps. Step width variability was overall the most reliable variable across groups and speed conditions.

The validity of the Gait Variability Index for individuals with mild to moderate Parkinson's disease.

Increased step-to-step variability is a feature of gait in individuals with Parkinson's disease (PD) and is associated with increased disease severity and reductions in balance and mobility. The Gait Variability Index (GVI) quantifies gait variability in spatiotemporal variables where a score ≥100 indicates a similar level of gait variability as the control group, and lower scores denote increased gait variability. The study aim was to explore mean GVI score and investigate construct validity of the index for individuals with mild to moderate PD. 100 (57 males) subjects with idiopathic PD, Hoehn & Yahr 2 (n=44) and 3, and ≥60 years were included. Data on disease severity, dynamic balance, mobility and spatiotemporal gait parameters at self-selected speed (GAITRite) was collected. The results showed a mean overall GVI: 97.5 (SD 11.7) and mean GVI for the most affected side: 94.5 (SD 10.6). The associations between the GVI and Mini- BESTest and TUG were low (r=0.33 and 0.42) and the GVI could not distinguish between Hoehn & Yahr 2 and 3 (AUC=0.529, SE=0.058, p=0.622). The mean GVI was similar to previously reported values for older adults, contrary to consistent reports of increased gait variability in PD compared to healthy peers. Therefore, the validity of the GVI could not be confirmed for individuals with mild to moderate PD in its current form due to low associations with validated tests for functional balance and mobility and poor discriminatory ability. Future work should aim to establish which spatiotemporal variables are most informative regarding gait variability in individuals with PD.

Simultaneous estimation of effects of gender, age and walking speed on kinematic gait data.

Analysis of variations in normal gait has received considerable attention over the last years. However, most such analyses are carried out on one explanatory variable at a time, and adjustments for other possibly influencing factors are often done using ad hoc methods. As a result, it can be difficult to know whether observed effects are actually a result of the variable under study. We wanted to simultaneously statistically test the effect of gender, age and walking speed on gait in a normal population, while also properly adjusting for the possibly confounding effects of body height and weight. Since point-by-point analysis does not take into account the time dependency in the data, we turned to functional data analysis (FDA). In FDA the whole gait curve is represented not by a set of points, but by a mathematical function spanning the whole gait cycle. We performed several multiple functional regression analyses, and the results indicate that walking speed is the main factor influencing gait in the reference material at our motion analysis laboratory. This effect is also largely unaffected by the presence of other variables in the model. A gender effect was also apparent in several planes and joints, but this effect was often more outspoken in the multiple than in the univariate regression analyses, highlighting the importance of adjusting for confounders like body height and weight.