Measurement of gait speed in older adults to identify complications associated with frailty: A systematic review

Several frailty screening tests in older cancer patients were developed but their statistical performance is low. We aimed to assess whether measurement of usual gait speed (GS) alone could be used as a frailty screening test in older cancer patients. This systematic review was conducted on "pub med" between 1984 and 2014 and included reviews and original studies. Eligibility criteria were: GS over a short distance, alone or included in composite walking tests (Timed Get Up and Go test: TGUG, Short Physical Performance Battery: SPPB) in older people (aged 65 and over) living in a community setting and predictive value of GS on medical complications associated with frailty. 46 articles were finally selected. GS alone is consensual and recommended for screening sarcopenia in elderly. A slow GS is predictive of early death, disability, falls and hospitalization/institutionalization in older people living in a community setting. GS alone is comparable to composite walking tests that do not provide additional information on the medical complications associated with frailty. Despite few studies in geriatric oncology, GS seems to predict overall survival and disability. We suggest GS over 4m (at a threshold of 1m/s) as a new frailty screening test in older cancer patients (65 and over) to guide the implementation of a comprehensive geriatric assessment during the initial management phase or during follow-up. Prospective cohort studies are needed to validate this algorithm and compare it with other screening tool.

Gait Speed Predicts Incident Disability: A Pooled Analysis

BACKGROUND

Functional independence with aging is an important goal for individuals and society. Simple prognostic indicators can inform health promotion and care planning, but evidence is limited by heterogeneity in measures of function.

METHODS

We performed a pooled analysis of data from seven studies of 27,220 community-dwelling older adults aged 65 or older with baseline gait speed, followed for disability and mortality. Outcomes were incident inability or dependence on another person in bathing or dressing; and difficulty walking ¼ - ½ mile or climbing 10 steps within 3 years.

RESULTS

Participants with faster baseline gait had lower rates of incident disability. In subgroups (defined by 0.2 m/s-wide intervals from <0.4 to ≥ 1.4 m/s) with increasingly greater gait speed, 3-year rates of bathing or dressing dependence trended from 10% to 1% in men, and from 15% to 1% in women, while mobility difficulty trended from 47% to 4% in men and 40% to 6% in women. The age-adjusted relative risk ratio per 0.1 m/s greater speed for bathing or dressing dependence in men was 0.68 (0.57-0.81) and in women: 0.74 (0.66-0.82); for mobility difficulty, men: 0.75 (0.68-0.82), women: 0.73 (0.67-0.80). Results were similar for combined disability and mortality. Effects were largely consistent across subgroups based on age, gender, race, body mass index, prior hospitalization, and selected chronic conditions. In the presence of multiple other risk factors for disability, gait speed significantly increased the area under the receiver operator characteristic curve.

CONCLUSION

In older adults, gait speed predicts 3 year incidence of bathing or dressing dependence, mobility difficulty, and a composite outcome of disability and mortality.

Intersegmental coordination scales with gait speed similarly in men and women

We applied principal component analysis (PCA) to thigh, shank, and foot elevation angles to examine the impact of speed on intra-limb coordination during gait. The specific aims were to (1) determine speed-related changes in segment loadings on three principal components (PCs) and (2) examine differences between men and women. The subjects (26 women, 21 men) walked overground at five self-selected paces (very slow, slow, normal, fast, very fast). PCA yielded percent variation (PV) explained by each PC and thigh, shank, and foot loadings on PC1-PC3. These parameters were regressed against the speed normalized to body height (BH/s) to derive individual and aggregate slopes and P values, separately for men and women. PV1 increased with speed, whereas PV2 and PV3 decreased (all P < 0.001). The loadings of thigh and foot segments on PC1 increased with speed (0.14 and 0.04 per BH/s, P < 0.001, respectively), and the loading of shank decreased (-0.10, P < 0.001). Compared to PC1, the changes in segment loadings on PC3 were the opposite (thigh -0.18, shank 0.09, foot -0.04 per BH/s, P < 0.001). The changes in segment loadings on PC2 were inconsistent and generally small. The only significance (P = 0.006), albeit a minor difference between men and women, was in the slope of thigh loading on PC2 (-0.005 ± 0.019 and 0.015 ± 0.026 per BH/s, respectively). We conclude that intersegmental coordination during gait scales with speed, with the greatest impact on the thigh segment, but no differently between men and women.

The influence of gait cadence on the ground reaction forces and plantar pressures during load carriage of young adults

Biomechanical gait parameters--ground reaction forces (GRFs) and plantar pressures--during load carriage of young adults were compared at a low gait cadence and a high gait cadence. Differences between load carriage and normal walking during both gait cadences were also assessed. A force plate and an in-shoe plantar pressure system were used to assess 60 adults while they were walking either normally (unloaded condition) or wearing a backpack (loaded condition) at low (70 steps per minute) and high gait cadences (120 steps per minute). GRF and plantar pressure peaks were scaled to body weight (or body weight plus backpack weight). With medium to high effect sizes we found greater anterior-posterior and vertical GRFs and greater plantar pressure peaks in the rearfoot, forefoot and hallux when the participants walked carrying a backpack at high gait cadences compared to walking at low gait cadences. Differences between loaded and unloaded conditions in both gait cadences were also observed.

Does gait speed contribute to sarcopenia case-finding in a postacute rehabilitation setting?

OBJECTIVE

The European Working Group of Sarcopenia in Older People (EWGSOP) has developed an algorithm based on gait speed measurement to begin sarcopenia case-finding in clinical practice, in which a cut-off point of <0.8m/s identifies risk for sarcopenia in community-dwelling older people. The objective of this study was to assess the application of the EWGSOP algorithm in hospitalised elderly patients with impaired functional capacity.

METHODS

One hundred in-patients (aged 84.1 SD 8.5, 62% women) were prospectively studied in a postacute care geriatric unit focused on rehabilitation. Sarcopenia was assessed by corporal composition (electrical bioimpedance), handgrip strength, and physical performance (gait speed). Other measurements were Charlson index, length of stay, and functional gain at discharge and 3-month follow-up. All patients were screened by the EWGSOP algorithm and sarcopenia was confirmed according to diagnostic criteria.

RESULTS

Gait speed was <0.8m/s in all cases and 58 patients had low muscle mass, which, according to the EWGSOP-algorithm, would indicate a diagnosis of sarcopenia. No differences were observed in functional capacity between these patients and those with normal muscle mass. When decreased handgrip strength was considered, 47 of these patients met the EWGSOP criteria for severe sarcopenia. In this group, differences in functional capacity were observed at discharge (Barthel 45.2 vs. 56.3, p=0.042) and 3-month follow-up (48.3 vs. 59.8, p=0.047).

CONCLUSION

The application of the EWGSOP algorithm in hospitalised, postacute, elderly patients with low gait speed suggested that muscle strength should be considered before confirming or discarding a sarcopenia diagnosis.

iCap: Instrumented assessment of physical capability

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Instrumented testing of five physical capability tasks with a single accelerometer.

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Evaluated on a large cohort of older adults.

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iCap provides robust quantitative data about physical capability.

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iCap captures gait and postural control data known as sensitive to ageing/pathology.

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Methodology may have practical utility in a wide range of surveys and studies.

Objectives

The aims of this study were to (i) investigate instrumented physical capability (iCap) as a valid method during a large study and (ii) determine whether iCap can provide important additional features of postural control and gait to categorise cohorts not previously possible with manual recordings.

Study design

Cross-sectional analysis involving instrumented testing on 74 adults who were recruited as part of a pilot intervention study; LiveWell. Participants wore a single accelerometer-based monitor (lower back) during standardised physical capability tests so that outcomes could be compared directly with manual recordings (stopwatch and measurement tape) made concurrently.

Main outcome measures

Time, distance, postural control and gait characteristics.

Results

Agreement between manual and iCap ranged from moderate to excellent (0.649–0.983) with mean differences between methods low and deemed acceptable. Additionally, iCap successfully quantified (i) postural control characteristics which showed sensitivity to distinguish between 5 variations of the standing balance test and (ii) 14 gait characteristics known to be sensitive to age/pathology.

Conclusions

Our findings show that iCap can provide robust quantitative data about physical capability during standardised tests while also providing sensitive (age/pathology) postural control and gait characteristics not previously quantifiable with manual recordings. The methodology which we propose may have practical utility in a wide range of clinical and public health surveys and studies, including intervention studies, where assessment could be undertaken within diverse settings. This will need to be tested in further validation studies in a wider range of settings.

Effects of different frequencies of rhythmic auditory cueing on the stride length, cadence, and gait speed in healthy young females

[Purpose] The aim of this study was to explore the effects of different frequencies of rhythmic auditory cueing (RAC) on stride length, cadence, and gait speed in healthy young females. The findings of this study might be used as clinical guidance of physical therapy for choosing the suitable frequency of RAC. [Subjects] Thirteen healthy young females were recruited in this study. [Methods] Ten meters walking tests were measured in all subjects under 4 conditions with each repeated 3 times and a 3-min seated rest period between repetitions. Subjects first walked as usual and then were asked to listen carefully to the rhythm of a metronome and walk with 3 kinds of RAC (90%, 100%, and 110% of the mean cadence). The three frequencies (90%, 100%, and 110%) of RAC were randomly assigned. Gait speed, stride length, and cadence were calculated, and a statistical analysis was performed using the SPSS (version 17.0) computer package. [Results] The gait speed and cadence of 90% RAC walking showed significant decreases compared with normal walking and 100% and 110% RAC walking. The stride length, cadence, and gait speed of 110% RAC walking showed significant increases compared with normal walking and 90% and 100% RAC walking. [Conclusion] Our results showed that 110% RAC was the best of the 3 cueing frequencies for improvement of stride length, cadence, and gait speed in healthy young females.

Limb contribution to increased self-selected walking speeds during body weight support in individuals poststroke

Individuals poststroke walk at faster self-selected speeds under some nominal level of body weight support (BWS) whereas nonimpaired individuals walk slower after adding BWS. The purpose of this study was to determine whether increases in self-selected overground walking speed under BWS conditions of individuals poststroke can be explained by changes in their paretic and nonparetic ground reaction forces (GRF). We hypothesize that increased self-selected walking speed, recorded at some nominal level of BWS, will relate to decreased braking GRFs by the paretic limb. We recruited 10 chronic (>12 months post-ictus, 57.5±9.6 y.o.) individuals poststroke and eleven nonimpaired participants (53.3±4.1 y.o.). Participants walked overground in a robotic device, the KineAssist Walking and Balance Training System that provided varying degrees of BWS (0-20% in 5% increments) while individuals self-selected their walking speed. Self-selected walking speed and braking and propulsive GRF impulses were quantified. Out of 10 poststroke individuals, 8 increased their walking speed 13% (p=0.004) under some level of BWS (5% n=2, 10% n=3, 20% n=3) whereas nonimpaired controls did not change speed (p=0.470). In individuals poststroke, changes to self-selected walking speed were correlated with changes in paretic propulsive impulses (r=0.68, p=0.003) and nonparetic braking impulses (r=-0.80, p=0.006), but were not correlated with decreased paretic braking impulses (r=0.50 p=0.14). This investigation demonstrates that when individuals poststroke are provided with BWS and allowed to self-select their overground walking speed, they are capable of achieving faster speeds by modulating braking impulses on the nonparetic limb and propulsive impulses of the paretic limb.

Changes of kinematic parameters of lower extremities with gait speed: a 3D motion analysis study

[Purpose] The purpose of this study was to investigate the changes in hip, knee and ankle kinematic variables of the lower extremities at different gait speeds. [Subjects and Methods] Forty healthy subjects who had no previous history of neurological, musculo-skeletal or other medical conditions that could affect gait were recruited. The subjects were asked to walk 10 m down a walkway at three different gait speeds: normal gait speed, and self-selected fast, and slow speeds. The experimental order was randomly chosen across these gaits. The hip, knee and ankle kinematic data were evaluated using a VICON 3D motion analysis system and force plates. [Results] The flexion peak and external rotation peak of the knee joint significantly increased with the increase of gait speed. The plantarflexion peaks of the ankle joint significantly increased with increase of gait speed. However, none of the kinematic data of the hip joint were significantly dependent on increase of gait speed. [Conclusion] The relationship of the knee and ankle joint can be described as coupling motion which is dependent on gait speed. Our present findings suggest that coupling motion of the knee joint and plantarflexion of the ankle joint significantly increase with increase of gait speed. These results will provide important insight into gait mechanisms for the evaluation of pathological populations.

Gait speed and cognitive decline over 2 years in the Ibadan study of aging

BACKGROUND

The evidence suggesting that gait speed may represent a sensitive marker for cognitive decline in the elderly requires support from diverse racial groups.

OBJECTIVE

We investigated the relationship between gait speed and cognitive decline over 2 years in a community dwelling sample of elderly Africans.

METHODS

Data are from the Ibadan study of aging (ISA) conducted among a household multi-stage probability sample of 2149 Yoruba Nigerians aged 65 years or older. Gait speed was measured as the time taken to complete a 3 or 4m distance at normal walking speed. We assessed cognitive functions with a modified version of the 10-word learning list and delay recall test, and examined the relationship between baseline gait speed, as well as gait speed changes, and follow-up cognition using multiple linear regression and longitudinal analyses using random effects.

RESULTS

Approximately 71% of 1461 participants who were dementia free and who had their gait speed measured at baseline (2007) were successfully followed up in two waves (2008 and 2009). Along with increasing age, poor health and economic status, a slower baseline gait speed was independently associated with poorer follow-up cognition in both linear regression (1.2 words, 95% CI=0.48-2.0) and longitudinal analyses (0.8 words, 95% CI=0.44-1.2). Also, a greater change in gait speed between 2007 and 2009 was associated with the worst follow-up cognition (0.3 words, 95% CI=0.09-0.51).

CONCLUSION

The finding that a substantial change in gait speed was associated with reduced cognitive performance is of potential importance to efforts aimed at early identification of cognitive disorders in this population.

Frailty and cardiovascular disease: potential role of gait speed in surgical risk stratification in older adults

Frailty is a state of late life decline and vulnerability, typified by physical weakness and decreased physiologic reserve. The epidemiology and pathophysiology of frailty share features with those of cardiovascular disease. Gait speed can be used as a measure of frailty and is a powerful predictor of mortality. Advancing age is a potent risk factor for cardiovascular disease and has been associated with an increased risk of adverse outcomes. Older adults comprise approximately half of cardiac surgery patients, and account for nearly 80% of the major complications and deaths following surgery. The ability of traditional risk models to predict mortality and major morbidity in older patients being considered for cardiac surgery may improve if frailty, as measured by gait speed, is included in their assessment. It is possible that in the future frailty assessment may assist in choosing among therapies (e.g., surgical vs. percutaneous aortic valve replacement for patients with aortic stenosis).

The impact of testing protocol on recorded gait speed

BACKGROUND

Gait speed predicts disability, cognitive decline, hospitalization, nursing home admission and mortality. Although gait speed is often measured in clinical practice and research, testing protocols vary widely and their impact on recorded gait speed has yet to be explored.

OBJECTIVES

Our purpose is to describe and compare gait speeds obtained from different testing protocols in the same individuals.

DESIGN

Cross-sectional.

SETTING

University research setting. Participants Subjects were 104 community-dwelling older adults who could ambulate household distances independently (mean age = 77.2 ± 6.1).

MEASUREMENTS

Gait speed was recorded over 4m using the protocols: (1) standing start, usual pace over ground, (2) walking start, usual pace over ground with an optokinetic device, (3) walking start, usual pace over ground with a stop watch (4) walking start, usual pace on a computerized walkway, and (5) walking start, fast pace on a computerized walkway. A linear mixed model and pairwise comparisons was used to compare gait speeds within individuals across different protocols.

RESULTS

Mean ± SD gait speed for each condition was: standing start, usual pace over ground 0.97 ± 0.23 m/s; walking start, usual pace over ground 1.14 ± 0.2 5m/s; walking start, usual pace on walkway 1.01 ± 0.26 m/s; and walking start, fast pace on walkway 1.31 ± 0.34 m/s. On average, the determined gait speed was 0.17 m/s faster during the walking compared to the standing start (p < .001), 0.07 m/s slower on the computerized walkway compared to over ground (p < .001), and 0.25 m/s faster during the fast pace compared to the usual pace walk (p < .001).

CONCLUSION

Starting protocol (standing vs. walking), testing surface (over ground vs. computerized walkway), and walking pace (usual vs. fast) impact recorded gait speed in older adults. Care should be taken when comparing gait speeds from studies with different testing protocols.

Association of insulin-like growth factor-1 with mild cognitive impairment and slow gait speed

The decrease in serum insulin-like growth factor-1 (IGF-I) with aging is related to the neurobiological processes in Alzheimer's disease. IGF-1 mediates effects of physical exercise on the brain, and cognition has a common pathophysiology with physical function, particularly with gait. The aim of this study was to examine whether mild cognitive impairment (MCI) and slow gait are associated with the serum IGF-1 level. A population survey was conducted in 3355 participants (mean age, 71.4 years). Cognitive functions (attention, executive function, processing speed, visuospatial skill, and memory), gait speed, and demographic variables were measured. All cognitive functions and gait speed were associated with the IGF-1 level (p < 0.001). The association of IGF-1 with slow gait was weakened by adjustment for covariates, but MCI and the combination of MCI and slow gait were independently related to the IGF-1 level in multivariate analysis (p < 0.05). Our findings support the association of a low IGF-1 level with reduced cognitive function and gait speed, particularly with a combination of MCI and slow gait.

Blood pressure, gait speed, and mortality in very old individuals: a population-based cohort study

OBJECTIVES

Clinical trials and observational studies have produced contradictory results regarding the association of blood pressure (BP) and mortality in people aged 80 years or older. Gait speed at usual pace has been shown to moderate this association in a population of noninstitutionalized people aged 65 years or older. The aims of this study were to investigate the association of BP with all-cause mortality in a representative sample of people aged 85 years or older and to assess whether gait speed moderates this association.

DESIGN, SETTING, AND PARTICIPANTS

A total of 806 participants in the population-based prospective Umeå 85+/GERDA study aged 85, 90, and 95 years or older.

MEASUREMENTS

Gait speed at usual pace was measured over 2.4 m. The main outcome was hazard ratios (HRs) for all-cause mortality according to systolic and diastolic BP categories in the total sample and in faster-walking (≥0.5 m/s, n = 312) and slower-walking (<0.5 m/s, n = 433) subcohorts; the latter also included habitually nonwalking participants. Comprehensive adjustments were made for sociodemographic and clinical characteristics associated with death.

RESULTS

Mean age and baseline systolic and diastolic BP were 89.6 ± 4.6 years, 146.8 ± 23.9 mm Hg, and 74.8 ± 11.1 mm Hg, respectively. Most (n = 561 [69%]) participants were women, 315 (39%) were care facility residents, and 566 (70%) were prescribed BP-lowering drugs. Within 5 years, 490 (61%) participants died. In the total sample and slower-walking subcohort, systolic BP appeared to be inversely associated with mortality, although not independent of adjustments. Among faster-walking participants, mortality risk after adjustment was more than 2 times higher in those with systolic BP of 140 to 149 mm Hg (HR = 2.25, 95% confidence interval [CI] = 1.03-4.94) and 165 mm Hg or higher (HR = 2.13, 95% CI = 1.01-4.49), compared with systolic BP of 126 to 139 mm Hg. Mortality risk was also independently higher in faster-walking participants with diastolic BP higher than 80 mm Hg, compared with diastolic BP of 75 to 80 mm Hg (HR = 1.76, 95% CI = 1.07-2.90).

CONCLUSION

The gait speed threshold of 0.5 m/s may be clinically useful for the distinction of very old people with and without increased all-cause mortality risk due to elevated systolic and diastolic BP.

Walking energetics, fatigability, and fatigue in older adults: the study of energy and aging pilot

BACKGROUND

Slow gait speed increases morbidity and mortality in older adults. We examined how preferred gait speed is associated with energetic requirements of walking, fatigability, and fatigue.

METHODS

Older adults (n = 36, 70-89 years) were categorized as slow or fast walkers based on median 400-m gait speed. We measured VO2peak by graded treadmill exercise test and VO2 during 5-minute treadmill walking tests at standard (0.72 m/s) and preferred gait speeds. Fatigability was assessed with the Situational Fatigue Scale and the Borg rating of perceived exertion at the end of walking tests. Fatigue was assessed by questionnaire.

RESULTS

Preferred gait speed over 400 m (range: 0.75-1.58 m/s) averaged 1.34 m/s for fast walkers versus 1.05 m/s for slow walkers (p < .001). VO2peak was 26% lower (18.5 vs 25.1ml/kg/min, p = .001) in slow walkers than fast walkers. To walk at 0.72 m/s, slow walkers used a larger percentage of VO2peak (59% vs 42%, p < .001). To walk at preferred gait speed, slow walkers used more energy per unit distance (0.211 vs 0.186ml/kg/m, p = .047). Slow walkers reported higher rating of perceived exertion during walking and greater overall fatigability on the Situational Fatigue Scale, but no differences in fatigue.

CONCLUSIONS

Slow walking was associated with reduced aerobic capacity, greater energetic cost of walking, and greater fatigability. Interventions to improve aerobic capacity or decrease energetic cost of walking may prevent slowing of gait speed and promote mobility in older adults.

The motor signature of mild cognitive impairment: results from the gait and brain study

BACKGROUND

Early motor changes associated with aging predict cognitive decline, which suggests that a "motor signature" can be detected in predementia states. In line with previous research, we aim to demonstrate that individuals with mild cognitive impairment (MCI) have a distinct motor signature, and specifically, that dual-task gait can be a tool to distinguish amnestic (a-MCI) from nonamnestic MCI.

METHODS

Older adults with MCI and controls from the "Gait and Brain Study" were assessed with neurocognitive tests to assess cognitive performance and with an electronic gait mat to record temporal and spatial gait parameters. Mean gait velocity and stride time variability were evaluated under simple and three separate dual-task conditions. The relationship between cognitive groups (a-MCI vs nonamnestic MCI) and gait parameters was evaluated with linear regression models and adjusted for confounders.

RESULTS

Ninety-nine older participants, 64 MCI (mean age 76.3±7.1 years; 50% female), and 35 controls (mean age 70.4±3.9 years; 82.9% female) were included. Forty-two participants were a-MCI and 22 were nonamnestic MCI. Multivariable linear regression (adjusted for age, sex, physical activity level, comorbidities, and executive function) showed that a-MCI was significantly associated with slower gait and higher dual-task cost under dual-task conditions.

CONCLUSION

Participants with a-MCI, specifically with episodic memory impairment, had poor gait performance, particularly under dual tasking. Our findings suggest that dual-task assessment can help to differentiate MCI subtyping, revealing a motor signature in MCI.

Association between forearm muscle thickness and age-related loss of skeletal muscle mass, handgrip and knee extension strength and walking performance in old men and women: a pilot study

Very little information is available concerning the relationship between handgrip strength and muscle size in the upper and lower extremities, especially the forearm muscle itself. To investigate the relationships among ultrasound-measured forearm muscle thickness from the radius and ulna bone interface with handgrip strength, knee extension strength, walking speed and absolute/relative total skeletal muscle mass (TMM), 32 Japanese men and 21 Japanese women ages 70-83 years had muscle thickness (MT) measured by ultrasound. In the forearm, two MTs (forearm-radius and forearm-ulna MT) were measured. TMM was estimated from an ultrasound-derived prediction equation. Handgrip-strength was significantly correlated with forearm-ulna MT in both men and women. There were no significant correlations between forearm MT and walking speed in either sex. In men, both forearm-radius and forearm-ulna MT were significantly correlated with TMM and TMM index. In women, a significant correlation was only observed between forearm-ulna MT and TMM index. Our results suggest that forearm-ulna MT may be a useful parameter for evaluating handgrip strength and TMM index in older Japanese men and women.

Strength and function response to clinical interventions of older women categorized by weakness and low lean mass using classifications from the Foundation for the National Institute of Health sarcopenia project

BACKGROUND

The Foundation for the National Institutes of Health Sarcopenia Project developed data-driven cut-points for clinically meaningful weakness and low lean body mass. This analysis describes strength and function response to interventions based on these classifications.

METHODS

In data from four intervention studies, 378 postmenopausal women with baseline and 6-month data were evaluated for change in grip strength, appendicular lean mass corrected for body mass index, leg strength and power, and short physical performance battery (SPPB). Clinical interventions included hormones, exercise, and nutritional supplementation. Differences in outcomes were evaluated between (i) those with and without weakness and (ii) those with weakness and low lean mass or with one but not the other. We stratified analyses by slowness (walking speed ≤ 0.8 m/s) and by treatment assignment.

RESULTS

The women (72±7 years; body mass index of 26±5kg/m(2)) were weak (33%), had low lean mass (14%), or both (6%). Those with weakness increased grip strength, lost less leg power, and gained SPPB score (p < .05) compared with nonweak participants. Stratified analyses were similar for grip strength and SPPB. With lean mass in the analysis, individuals with weakness had larger gains in grip strength and SPPB scores regardless of low lean mass (p < .01).

CONCLUSIONS

Older women with clinically meaningful muscle weakness increased grip strength and SPPB, regardless of the presence of low lean mass following treatment with interventions for frailty. Thus, results suggest that muscle weakness, as defined by the Foundation for the National Institutes of Health Sarcopenia Project, appears to be a treatable symptom.

Gait speed and hospitalization among ambulatory hemodialysis patients: USRDS special study data

AIM: To assess the association of measured gait speed with hemodialysis (HD) patients’ hospitalization, in conjunction with, and apart from, recent fall history.

METHODS: Gait speed was measured by a standard protocol and falls during the past 12 mo were ascertained for a prevalent multi-center HD cohort (n = 668) aged 20-92. Hospitalization during the past 12 mo was identified in the patient’s clinic records, and the first hospitalization after gait speed assessment (or the competing event of death) was identified in the 2013 United States Renal Data System Standard Analysis Files.

RESULTS: Slow gait speed, defined as < 0.8 m/s, characterized 34.7% of the patients, and 27.1% had experienced a recent fall. Patients with slow gait speed but without a history of recent falls were 1.79 times more likely to have been hospitalized during the past 12 mo (OR = 1.79, 95%CI: 1.11-2.88, P = 0.02), and patients with slow gait speed and a history of recent falls were over two times more likely to have been hospitalized (OR = 2.10, 95%CI: 1.19-3.73, P = 0.01), compared with patients having faster gait speed and no recent fall history. Prospective examination of gait speed/fall history status in relation to first hospitalization (or death) incurred by the end of follow-up December 31, 2011 also showed that slow gait speed was associated with these events in conjunction with a history of falls (HR = 1.54, 95%CI: 1.04-2.30, P = 0.03).

CONCLUSION: The International Task Force on Nutrition and Aging reported that gait speed is a powerful predictor for older adults of adverse outcomes such as hospitalization. In our data, gait speed--apart from, as well as in conjunction with, recent fall history--was associated with HD patients’ hospitalization for multiple causes. Gait speed may be a sensitive health indicator among HD patients across the age spectrum.

[Calf circumference and its association with gait speed in elderly participants at Peruvian Naval Medical Center]

OBJECTIVE

To evaluate the association between calf circumference and gait speed in elderly patients 65 years or older at Geriatric day clinic at Peruvian Centro Médico Naval.

MATERIAL AND METHODS

Cross-sectional, retrospective study. We assessed 139 participants, 65 years or older at Peruvian Centro Médico Naval including calf circumference, gait speed and Short Physical Performance Battery. With bivariate analyses and logistic regression model we search for association between variables.

RESULTS

The age mean was 79.37 years old (SD: 8.71). 59.71% were male, the 30.97% had a slow walking speed and the mean calf circumference was 33.42cm (SD: 5.61). After a bivariate analysis, we found a calf circumference mean of 30.35cm (SD: 3.74) in the slow speed group and, in normal gait group, a mean of 33.51cm (SD: 3.26) with significantly differences. We used logistic regression to analyze association with slow gait speed, founding statistically significant results adjusting model by disability and age.

CONCLUSION

Low calf circumference is associated with slow speed walk in population over 65 years old.

Single and dual task tests of gait speed are equivalent in the prediction of falls in older people: a systematic review and meta-analysis

Although simple assessments of gait speed have been shown to predict falls as well as hospitalisation, functional decline and mortality in older people, dual task gait speed paradigms have been increasingly evaluated with respect to fall prediction. Some studies have found that dual task walking paradigms can predict falls in older people. A systematic review and meta-analysis was conducted to determine whether dual task walking paradigms involving a secondary cognitive task have greater ability to predict falls than single walking tasks. The meta-analytic findings indicate single and dual task tests of gait speed are equivalent in the prediction of falls in older people and sub-group analyses revealed similar findings for studies that included only cognitively impaired participants, slow walkers or used secondary mental-tracking or verbal fluency tasks.

Pathways linking regional hyperintensities in the brain and slower gait

IMPORTANCE

Cerebral white matter hyperintensities (WMHs) are involved in the evolution of impaired mobility and executive functions. Executive functions and mobility are also associated. Thus, WMHs may impair mobility directly, by disrupting mobility-related circuits, or indirectly, by disrupting circuits responsible for executive functions. Understanding the mechanisms underlying impaired mobility in late life will increase our capacity to develop effective interventions.

OBJECTIVE

To identify regional WMHs most related to slower gait and to examine whether these regional WMHs directly impact mobility, or indirectly by executive functions.

DESIGN

Cross-sectional study. Twenty-one WMH variables (i.e., total WMH volume and WMHs in 20 tracts), gait speed, global cognition (Modified Mini-Mental State Examination; 3MS), and executive functions and processing speed (Digit-Symbol Substitution Test; DSST) were assessed. An L1-L2 regularized regression (i.e., Elastic Net model) identified the WMH variables most related to slower gait. Multivariable linear regression models quantified the association between these WMH variables and gait speed. Formal tests of mediation were also conducted.

SETTING

Community-based sample.

PARTICIPANTS

Two hundred fifty-three adults (mean age: 83years, 58% women, 41% black).

MAIN OUTCOME MEASURE

Gait speed.

RESULTS

In older adults with an average gait speed of 0.91m/sec, total WMH volume, WMHs located in the right anterior thalamic radiation (ATRR) and frontal corpuscallosum (CCF) were most associated with slower gait. There was a >10% slower gait for each standard deviation of WMH in CCF, ATRR or total brain (standardized beta in m/sec [p value]: -0.11 [p=0.046], -0.15 [p=0.007] and -0.14 [p=0.010], respectively). These associations were substantially and significantly attenuated after adjustment for DSST. This effect was stronger for WMH in CCF than for ATRR or total WMH (standardized beta in m/sec [p value]: -0.07 [p=0.190], -0.12 [p=0.024] and -0.10 [p=0.049], respectively). Adjustment for 3MS did not change these associations. The mediation analyses also found that DSST significantly mediated the associations between WMHs and gait speed. Our models were adjusted for age, sex, BMI, quadriceps strength, years of education, standing height, and prevalent hypertension.

CONCLUSION

The impact, direct or indirect, of WMHs on gait speed depended on their location and was mediated by executive function. Thus, multi-faceted interventions targeting executive control functions as well as motor functions, such as balance and strength training, are candidates to the maintenance of mobility across the lifespan.

Does dance-based therapy increase gait speed in older adults with chronic lower extremity pain: a feasibility study

A decreased gait speed in older adults can lead to dependency when the individuals are no longer able to participate in activities or do things for themselves. Thirty-seven senior apartment residents (31 females; Mean age=80.6 years; SD=8.9) with lower extremity pain/stiffness participated in a feasibility and preliminary efficacy study of 12 weeks (24 sessions). Healthy-Steps dance therapy compared to a wait-list control group. Small improvements in gait speed ([ES]=0.33) were noted for participants completing 19-24 dance sessions. Improvements in gait speed measured by a 10 Meter Walk Test (0.0517 m/s) exceeded 0.05 m/s, a value deemed to be meaningful in community dwelling older adults. These feasibility study findings support the need for additional research using dance-based therapy for older adults with lower extremity pain.

Functional capacity and fear of falling in cancer patients undergoing chemotherapy

Cancer patients, particularly during chemotherapy, often encounter functional status limitations. This study examines fear of falling, balance, gait and lower limb strength in cancer patients during ongoing or recently completed (≤12 months) chemotherapeutic treatment in comparison to age-matched and senior controls (≥65 years). Data were obtained from 69 subjects; 21 cancer patients (51±7 years) with histological confirmed diagnosis and two control groups (2×n=24): one age-matched (53±7 years) and one senior group (70±3 years). Fear of falling (FoF) was evaluated using the Falls Efficacy Scale-International Version. Motor function measurement included postural sway (centre of pressure) in upright stance with eyes covered, gait speed (comfortable fluid walking) and maximum voluntary isometric quadriceps strength (MIVF). One-way ANOVA followed by corrected post hoc paired-sample t-test revealed inferior values in cancer patients than in age-matched healthy regarding all parameters. Gait speed and MIVF of cancer patients were higher than in the senior control group (p<.05), whereas their FoF and postural sway were comparable (p>.05). Physical performance parameters of cancer patients were found to be lower in comparison to healthy age-matched subjects. Cancer patients show physical impairments which may limit independence and may increase fall risk. The present findings call for routine screening of physical function in cancer patients, and further stress the relevance of exercise interventions during and after chemotherapy.

The Arm Posture Score for assessing arm swing during gait: an evaluation of adding rotational components and the effect of different gait speeds

In 3D gait analysis, quantification of leg movements is well established, whereas a measure of arm swing has been lacking. Recently, the Arm Posture Score (APS) was introduced to characterize arm movements in children with cerebral palsy, including information from four variables (APS4) in the sagittal and frontal planes. A potential limitation of the APS is that it does not include rotational movements and has not yet been evaluated with regard to gait speed. The aims of this study were (i) to investigate the effect on APS of adding two components of arm rotation (APS6) and (ii) to determine the influence of gait speed on the APS measures, when applied to non-disabled adults. Forty-two subjects walked 10 m at a self-selected speed (1.34 m/s), and in addition a subgroup of 28 subjects walked at a slow speed (0.66 m/s) set by a metronome. Data were collected from markers in a whole-body set up and by eight optoelectronic cameras. The results demonstrated significantly higher APS6 than APS4 values for both arms, irrespective of gait speed. Speed condition, whether self-selected or slow, had a significant effect on both APS measures. The two additional arm components are suggested to provide relevant information about arm swing during walking. However, APS6 needs to be implemented in gait analysis of individuals with gait arm pathologies in order to further examine its utility. We recommend that gait speed should to be taken into account when using APS measures to quantify arm swing during gait.

Gait speed in ambulant older people in long term care: a systematic review and meta-analysis

BACKGROUND

Gait speed, recently proposed as the sixth vital sign of geriatric assessment, is a strong predictor of adverse outcomes. Walking faster than 1.0 m/s is associated with better survival in community-dwelling older adults, and a recent meta-analysis of older adults in clinical settings estimated usual gait speed to be 0.58 m/s. Here, we aimed to review gait speed values for long term care residents.

METHODS

Relevant databases were systematically searched for original research studies published prior to December 2012. Inclusion criteria were participants living in long term care, mean age >70 years, and gait speed measured over a short distance. Meta-analysis determined gait speed data adjusting for covariates including age, sex, and cognition.

RESULTS

Final data included 2888 participants from 34 studies. The percentage of residents ineligible because of inability to mobilize was stated in only 1 study. Of the 34 studies, 22 reported cognitive status using the Mini-Mental State Examination. Usual pace and maximal pace gait speeds were determined separately using a random effects model. No association between gait speed and covariates was found. Usual pace gait speed was 0.475 m/s (95% confidence interval 0.396-0.554) and maximal pace was 0.672 m/s (95% confidence interval 0.532-0.811).

CONCLUSIONS

In ambulant older people in long term care, gait speed is slow but remains functional. However, since many residents are likely to have been ineligible to participate in assessments, these results cannot be generalized to the long term care population as a whole.

Limitations in gait speed persist at discharge from subacute rehabilitation

[Purpose] Walking speed is related to important outcomes such as mortality and is fundamental to independent and safe ambulation in the community. The objectives of this study were to determine if the discharge gait speed of patients completing subacute rehabilitation was slow relative to normative and street crossing reference values, and whether such speed was associated with age, gender, or diagnosis. [Subjects and Methods] Consecutive patients admitted to a subacute rehabilitation facility were screened based on inclusion and exclusion criteria. Participants were 109 patients (56 women) 60 to 98 (mean=78.2) years old who were divided into 10 diagnostic categories. Gait speed was measured over a distance of 5.2 meters as patients walked at their most comfortable speed beyond a designated finish line. Timing with a digital stopwatch began after an acceleration distance of 1 meter and ceased as patients crossed the finish line. [Results] The patients' comfortable gait speed (mean=0.58; SD=0.19; range=0.09–1.10 m/s) was significantly less than 1.0m/s (normal reference value) (1.11±0.15 m/s) but significantly greater than that required for crossing the street (0.49 m/s). Nevertheless, 27.5% of patients did not achieve a walking speed of 0.49 m/s. Speed was inversely related to age and was lower among women, but it was not affected by diagnostic category. [Conclusion] Gait speed remains limited when patients are discharged home from subacute rehabilitation and was slowest among older women patients. Further therapy may be warranted for such patients after discharge.

Minimal clinically important difference for comfortable speed as a measure of gait performance in patients undergoing inpatient rehabilitation after stroke

[Purpose] The purpose of this retrospective study was to determine the minimal clinically important difference for comfortable gait speed for patients with stroke. [Subjects] Data were analyzed from 35 patients undergoing inpatient rehabilitation. [Methods] Two characteristics of gait were measured, assistance required and comfortable gait speed. Patients were grouped as either experiencing or not experiencing a decrease of 2 or more levels of assistance required over the course of rehabilitation. Receiver operating characteristic curve analysis was used to identify the change in gait speed that best differentiated between patients who did and did not experience the requisite decrease in assistance required for gait. [Results] Twenty-one patients decreased 2 or more levels of assistance whereas 14 did not. Walking speed increased significantly more in the group who experienced a decrease in assistance of at least 2 levels. The receiver operating characteristic curve analysis showed a change in walking speed of 0.13 m/s best distinguished between patients who did versus did not experience a reduction in assistance required. [Conclusion] An improvement in gait speed of 0.13 m/s or more is clinically important in patients with stroke.

Influence of gait speed on the control of mediolateral dynamic stability during gait initiation

This study investigated the influence of gait speed on the control of mediolateral dynamic stability during gait initiation. Thirteen healthy young adults initiated gait at three self-selected speeds: Slow, Normal and Fast. The results indicated that the duration of anticipatory postural adjustments (APA) decreased from Slow to Fast, i.e. the time allocated to propel the centre of mass (COM) towards the stance-leg side was shortened. Likely as an attempt at compensation, the peak of the anticipatory centre of pressure (COP) shift increased. However, COP compensation was not fully efficient since the results indicated that the mediolateral COM shift towards the stance-leg side at swing foot-off decreased with gait speed. Consequently, the COM shift towards the swing-leg side at swing heel-contact increased from Slow to Fast, indicating that the mediolateral COM fall during step execution increased as gait speed rose. However, this increased COM fall was compensated by greater step width so that the margin of stability (the distance between the base-of-support boundary and the mediolateral component of the "extrapolated centre of mass") at heel-contact remained unchanged across the speed conditions. Furthermore, a positive correlation between the mediolateral extrapolated COM position at heel-contact and step width was found, indicating that the greater the mediolateral COM fall, the greater the step width. Globally, these results suggest that mediolateral APA and step width are modulated with gait speed so as to maintain equivalent mediolateral dynamical stability at the time of swing heel-contact.

Effects of various gait speeds on the latissimus dorsi and gluteus maximus muscles associated with the posterior oblique sling system

[Purpose] This study investigated the effect of different gait speeds on the muscle activities of the latissimus dorsi and gluteus maximus muscles in relation to the posterior oblique sling system. [Subjects] We recruited 14 young adult males. [Methods] We measured the left latissimus dorsi muscle activity and right gluteus maximus muscle activity of all subjects while they walked on a treadmill at speeds of 1.5 km/h, 3.5 km/h and 5.5 km/h. [Results] There was a significant increase in latissimus dorsi muscle activity with a treadmill speed of 5.5 km/h compared with 1.5 km/h and 3.5 km/h. The gluteus maximus muscle activity significantly increased in the order of 1.5 km/h < 3.5 km/h < 5.5 km/h. [Conclusion] The present results indicate that arm swing connected to increasing gait speed influences the muscle activity of the lower limbs through the posterior oblique sling system.

Resonance-based oscillations could describe human gait mechanics under various loading conditions

The oscillatory behavior of the center of mass (CoM) and the corresponding ground reaction force (GRF) of human gait for various gait speeds can be accurately described in terms of resonance using a spring-mass bipedal model. Resonance is a mechanical phenomenon that reflects the maximum responsiveness and energetic efficiency of a system. To use resonance to describe human gait, we need to investigate whether resonant mechanics is a common property under multiple walking conditions. Body mass and leg stiffness are determinants of resonance; thus, in this study, we investigated the following questions: (1) whether the estimated leg stiffness increased with inertia, (2) whether a resonance-based CoM oscillation could be sustained during a change in the stiffness, and (3) whether these relationships were consistently observed for different walking speeds. Seven healthy young subjects participated in over-ground walking trials at three different gait speeds with and without a 25-kg backpack. We measured the GRFs and the joint kinematics using three force platforms and a motion capture system. The leg stiffness was incorporated using a stiffness parameter in a compliant bipedal model that best fitted the empirical GRF data. The results showed that the leg stiffness increased with the load such that the resonance-based oscillatory behavior of the CoM was maintained for a given gait speed. The results imply that the resonance-based oscillation of the CoM is a consistent gait property and that resonant mechanics may be useful for modeling human gait.

Compliant bipedal model with the center of pressure excursion associated with oscillatory behavior of the center of mass reproduces the human gait dynamics

Although the compliant bipedal model could reproduce qualitative ground reaction force (GRF) of human walking, the model with a fixed pivot showed overestimations in stance leg rotation and the ratio of horizontal to vertical GRF. The human walking data showed a continuous forward progression of the center of pressure (CoP) during the stance phase and the suspension of the CoP near the forefoot before the onset of step transition. To better describe human gait dynamics with a minimal expense of model complexity, we proposed a compliant bipedal model with the accelerated pivot which associated the CoP excursion with the oscillatory behavior of the center of mass (CoM) with the existing simulation parameter and leg stiffness. Owing to the pivot acceleration defined to emulate human CoP profile, the arrival of the CoP at the limit of the stance foot over the single stance duration initiated the step-to-step transition. The proposed model showed an improved match of walking data. As the forward motion of CoM during single stance was partly accounted by forward pivot translation, the previously overestimated rotation of the stance leg was reduced and the corresponding horizontal GRF became closer to human data. The walking solutions of the model ranged over higher speed ranges (~1.7 m/s) than those of the fixed pivoted compliant bipedal model (~1.5m/s) and exhibited other gait parameters, such as touchdown angle, step length and step frequency, comparable to the experimental observations. The good matches between the model and experimental GRF data imply that the continuous pivot acceleration associated with CoM oscillatory behavior could serve as a useful framework of bipedal model.

Gait initiation: the first four steps in adults aged 20-25 years, 65-79 years, and 80-91 years

Transitioning from standing to walking requires equilibrium to be maintained while a forward propulsive force is generated. The ability to manage these competing demands is compromised by the progressive sensory, neural and motor declines associated with aging. The purpose of this study was to establish the age-related changes in the first four steps of gait in three age groups: 20-25 years old (yo) (N=19), 65-79 yo (N=11), and 80-91 yo (N=18). Participants stood comfortably and then walked at a self-selected pace for 3.2m. Gait speed and step length (SL) both significantly decreased with each age category at each of the first four steps. However, the gait speed changes suggest that older groups control speed in a principled manner across the four steps, which was similar to the speed control of 20-25 yo. With successive steps, 20-25 yo demonstrated a progressive decrease in SL variability, but SL variability of the two older groups did not change. Step width (SW) did not change as a function of age, but SW variability was higher for the two older groups. Higher SL and SW variability may reflect more errors in foot placement and/or decreased center of mass control in the older groups. Further, it appears that AP COM control improves with successive steps in young adults while ML COM control decreases with successive steps in all age groups. When comparing the two older groups, healthy 80-91 yo walked slower with a shorter SL, but did not demonstrate changes associated with falls (SL and/or SW variability).

Effect of gait speed changes on foot loading characteristics in children

Gait speed has been shown to influence foot loading patterns in adults but the mechanism has not been investigated in children. The present study investigated the effects of changes in gait speed on foot loading characteristics in 20 typically developing children who participated in plantar pressure measurements at normal, slow and fast walking speeds. In spite of shorter contact times in the fast walking speed condition, significantly increased foot loading was seen in the hindfoot, medial and central forefoot and toes while it slightly decreased in the lateral midfoot and forefoot. The results generally confirm the findings in adults that gait speed does not uniformly affect foot loading characteristics and that these effects should be kept in mind when comparing different subject groups or children at repeated measurement occasions.

Effects of walking speed on asymmetry and bilateral coordination of gait

The mechanisms regulating the bilateral coordination of gait in humans are largely unknown. Our objective was to study how bilateral coordination changes as a result of gait speed modifications during over ground walking. 15 young adults wore force sensitive insoles that measured vertical forces used to determine the timing of the gait cycle events under three walking conditions (i.e., usual-walking, fast and slow). Ground reaction force impact (GRFI) associated with heel-strikes was also quantified, representing the potential contribution of sensory feedback to the regulation of gait. Gait asymmetry (GA) was quantified based on the differences between right and left swing times and the bilateral coordination of gait was assessed using the phase coordination index (PCI), a metric that quantifies the consistency and accuracy of the anti-phase stepping pattern. GA was preserved in the three different gait speeds. PCI was higher (reduced coordination) in the slow gait condition, compared to usual-walking (3.51% vs. 2.47%, respectively, p=0.002), but was not significantly affected in the fast condition. GRFI values were lower in the slow walking as compared to usual-walking and higher in the fast walking condition (p<0.001). Stepwise regression revealed that slow gait related changes in PCI were not associated with the slow gait related changes in GRFI. The present findings suggest that left-right anti-phase stepping is similar in normal and fast walking, but altered during slow walking. This behavior might reflect a relative increase in attention resources required to regulate a slow gait speed, consistent with the possibility that cortical function and supraspinal input influences the bilateral coordination of gait.

Dimensions of physical frailty and cognitive function in older adults with amnestic mild cognitive impairment

OBJECTIVE

The objective of this study was to examine relationships between dimensions of physical frailty and severity of cognitive impairment in older adults with amnestic mild cognitive impairment (aMCI).

PATIENTS AND METHODS

The prevalence of physical frailty dimensions including slow gait speed, low physical activity, and low grip strength was examined among 201 sedentary older adults with aMCI. Associations between dimensions of physical frailty and severity of cognitive impairment, as measured with the Alzheimer's Disease Assessment Scale-Cognitive Subscale (ADAS-Cog) and individual dimensions of cognitive function were examined using multiple linear regression models.

RESULTS

Greater than 50% of participants met physical frailty criteria on dimensions of slow gait speed, low physical activity and low grip strength. Slower gait speed was associated with elevated severity of cognitive impairment. Both gait speed and physical activity were associated with individual dimensions cognitive function.

CONCLUSIONS

Dimensions of physical frailty, particularly gait speed, were associated with severity of cognitive impairment, after adjusting for age, sex and age-related factors. Further studies are needed to investigate mechanisms and early intervention strategies that assist older adults with aMCI to maintain function and independence.

Assessing the temporal relationship between cognition and gait: slow gait predicts cognitive decline in the Mayo Clinic Study of Aging

BACKGROUND

The association between gait speed and cognition has been reported; however, there is limited knowledge about the temporal associations between gait slowing and cognitive decline among cognitively normal individuals.

METHODS

The Mayo Clinic Study of Aging is a population-based study of Olmsted County, Minnesota, United States, residents aged 70-89 years. This analysis included 1,478 cognitively normal participants who were evaluated every 15 months with a nurse visit, neurologic evaluation, and neuropsychological testing. The neuropsychological battery used nine tests to compute domain-specific (memory, language, executive function, and visuospatial skills) and global cognitive z-scores. Timed gait speed (m/s) was assessed over 25 feet (7.6 meters) at a usual pace. Using mixed models, we examined baseline gait speed (continuous and in quartiles) as a predictor of cognitive decline and baseline cognition as a predictor of gait speed changes controlling for demographics and medical conditions.

RESULTS

Cross-sectionally, faster gait speed was associated with better performance in memory, executive function, and global cognition. Both cognitive scores and gait speed declined over time. A faster gait speed at baseline was associated with less cognitive decline across all domain-specific and global scores. These results were slightly attenuated after excluding persons with incident mild cognitive impairment or dementia. By contrast, baseline cognition was not associated with changes in gait speed.

CONCLUSIONS

Our study suggests that slow gait precedes cognitive decline. Gait speed may be useful as a reliable, easily attainable, and noninvasive risk factor for cognitive decline.