Gait characteristics during dual task walking in elderly subjects of different age

doi:10.21203/rs.3.rs-3132375/v1

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Gait characteristics during dual task walking in elderly subjects of different age

https://doi.org/10.21203/rs.3.rs-3132375/v1

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Purpose: In older age walking ability gradually decreases due to factors including impaired balance, reduced muscle strength, and impaired vision and proprioception. Further, cognitive functions play a great role during walking and with age cognitive functions gradually decline. There is a greater variability when the demands during walking increase, in dual and multiple task situations.

The aim was to analyze gait parameters while performing demanding cognitive and motor dual task in the different age-related healthy elderly subjects.

Method: Total of 132 healthy individuals (54 males, 78 females) were divided in three groups –55 to 65 years, 66 and 75 and 76 to 85 years. Subjects performed a basic walking task, a dual-motor task, a dual-mental task, and a combined motor and mental task while walking. Gait parameters as cycle time, stride length, swing time and double support time were noted, as well as variability of those parameters.

Results: Cycle time was was increased and stride length was shorter in the group >76 years in comparison to the group 51-65 years in all test conditions. A comparison of all three groups did not show significant difference in swing time, while double support time was increased in the same group.

Conclusions: Changes are observed when gait is performed simultaneously with additional motor or cognitive task. Early detection of gait disorders can help identify elderly people at increased risk of falls. Employing dual task paradigm during gait assessment in healthy elderly may help identify cognitive impairment early in the disturbances course.

Healthy elderly

aging

gait cycle

stride cycle

The aim was to analyze gait parameters while performing demanding cognitive and motor dual task in the different age-related healthy elderly subjects.

Findings:

Cycle time was was increased and stride length was shorter in the elderly groups compared to the group 51-65 years in all test conditions.

Message:

Employing dual task paradigm during gait assessment in healthy elderly may help identify cognitive impairment early in the disturbances course.

Gait is a complex motor activity of rhythmic movements of lower limbs that provide support and propulsion for locomotion [1]. Gait consists of repeated steps building up a gait cycle. Gait cycle is defined as a distance starting with the contact of the heel of one foot with the ground and ending with the repeated contact of the same foot. Preserved gait control, in addition to efficient integration of motor and sensory information, also requires an active role of cognitive functions [2].

In older age, walking ability gradually decreases due to various factors including impaired balance, reduced muscle strength in the lower limbs, impaired vision and proprioception, and deterioration of general health and appearance of some medical conditions [3–5]. The gait of the elderly is associated with greater variability and changes in certain characteristics compared to the gait of younger persons [3, 6]. For example, the walking speed correlates with general health and functional status; if the walking speed is lower, there is a higher risk of falls, hospitalization, mortality and reduced quality of life [7].

Cognitive functions play a greater role during walking than previously assumed [e.g. 8]. With age cognitive functions gradually decline [9]. Influence of cognitive impairment, specifically executive dysfunction and attention problems on gait performance in healthy elderly subjects has been reported [e.g. 8, 10, 11]. Large longitudinal study with more then 3000 healthy subjects showed that spatial and temporal changes in gait parameters were associated with cognitive decline in elderly individuals [12]. Poor executive functioning and processing speed were associated with an increased double support time and step time variablity, while memory was not associated with gait changes [4]. Even in young individuals, gait and its parameters (such as speed) are not automated, and also require partial involvement of attention [13].

The association of gait and cognitive functions is particularly significant during dual task walking [11, 14, 15]. There is a greater variability when the demands during walking increase, e.g. in dual and multiple task situations [11, 16]. Hollman and colleagues [16] reported that healthy older individuals walked more slowly with a greater variability in stride velocity during the dual task condition compared to middle aged and young individuals, presumably due to impaired cognitive performance in elderly.

The aim of the present study was to analyze gait parameters while performing demanding cognitive and motor dual task in the different age-related healthy elderly subjects.

Subjects

In the period from January 2018 to December 2019 a total of 132 healthy individuals (54 males, 78 females) were recruited among the spouses, friends and relatives of the patients at Neurology Clinic, Clinical Center of Serbia, Faculty of Medicine, University of Belgrade. Subjects were divided in three groups – from 55 to 65 years (54 subjects, mean age 55,83 ± SD 4,17 years), between 66 and 75 years (54 subjects, mean age 68,13 ± SD 2,69 years), and from 76 to 85 (24 subjects, mean age 81,04 ± SD 4,47 years). Individuals suffering from neurological disorders, orthopedic diseases or other medical conditions that could impair their independent walking as well as those that used cane or walker were not included in the study. The study was approved by Ethical Committee of the Faculty of Medicine, University of Belgrade and written informed consent was obtained from each participant prior to the inclusion in this study. The study was performed in accordance with the ethical standards of the Declaration of Helsinki and its later amendments.

Experimental protocol

Subjects performed a self-paced basic walking task, a dual-motor task, a dual-mental task, and a combined motor and mental task while walking [17]. The motor dual task comprised of comfortable walking with a large glass fully filled with water, with the aim not to spill the water. The mental dual task was serial „7“ subtraction while walking, starting from numbers 100, 95, 90, or 105, chosen randomly, whereas the combined motor and mental task required the subjects to perform serial subtractions as described above, while walking with glass filled with water. Prioritization was not given for this task. Measurements were performed using GAITRite electronic walkway of 5.5m active area (CIR Systems, Havertown, PA). Participants performed six passes, three times down the corridor and back, at their comfortable gait velocity, starting and ending their walks approximately 1–1.5m before and after the walkway. The walking distance was approximately 50 m (six GAITRite passes x 8–9 m) for each given task (basic, motor, mental, and combined) amounting to 200 m of walking, which was sufficient to adequately assess gait variability. While performing these tasks, parameters as cycle time - CT, stride length - SL, swing time - SWT and double support time - DST were noted. Variability of gait parameters was calculated through the coefficient of variation (CV) - variability normalized to mean value (CV = 100xSD/mean) [17, 18].

Statistical analysis

ANOVA with post hoc Bonferroni correction was used to assess differences between three investigated groups. Repeated measures ANOVA was used to calculate differences between parameters in different test conditions. Results were depicted as p-values (significance p < 0.05, Bonferroni correction). Statistical analysis was performed using SPSS 17.0 (SPSS, Chicago, IL).

Comparison of the gait parameters and their CVs in three groups of subjects during performance of different walking tasks (base walk (B), walk with motor task (M), walk with mental task (7) and walk with combined task (C)) is presented in Fig. 1, as well as in Tables 1 and 2.

Table 1. Cycle time (CT), stride length (SL), swing time (SWT) and double support time (DST) – mean values with SDs and CVs for three tested groups performing the following walking tasks: base walk, motor task, mental task and combined motor and mental tasks.

Groups	Base walk			Motor task			Mental task			Combined task
	CT	± SD	CV	CT	± SD	CV	CT	± SD	CV	CT	± SD	CV
51–65	1.06	0.09	4.12	1.06	0.09	3.01	1.13	0.12	0.41	0.02	1.10	3.30
66–75	1.12	0.15	4.40	1.10	0.12	2.93	1.22 *	0.20	0.40	0.03 *	1.17	3.60
> 76	1.16**	0.12	5.57	1.18 **^,#	0.10	5.82	1.26 **	0.13	1.19	0.03 **	1.20	3.11
P value	0.003		0.265	< 0.001		0.352	0.02		0.371	0.02		0.649
	SL	± SD	CV	SL	± SD	CV	SL	± SD	CV	SL	± SD	CV
51–65	128.53	10.92	2.98	124.67	11.36	2.73	122.23	12.46	3.72	117.93	12.83	3.56
66–75	122.78	15.57	3.76	118.47	14.93	3.43 *	113.13 **	16.17	5.49 **	110.62 *	14.69	5.31 **
> 76	112.02 **^,##	19.39	4.39 **	104.49 **^,##	15.70	4.35 **^,#	99.65 **^,##	17.31	6.77 **	100.27 **	14.07	6.34 **
P value	< 0.001		0.003	< 0.001		< 0.001	< 0.001		< 0.001	< 0.001		< 0.001
	SWT	± SD	CV	SWT	± SD	CV	SWT	± SD	CV	SWT	± SD	CV
51–65	0.38	0.04	9.20	0.37	0.03	8.46	0.39	0.04	9.88	0.39	0.04	9.62
66–75	0.38	0.04	11.61	0.37	0.04	9.71	0.40	0.05	12.28	0.39	0.05	11.39
> 76	0.38	0.03	12.36	0.37	0.03	10.85	0.39	0.04	15.91**^,#	0.39	0.05	15.01 **
P value	0.954		0.067	0.585		0.281	0.805		< 0.001	0.945		0.01
	DST	± SD	CV	DST	± SD	CV	DST	± SD	CV	DST	± SD	CV
51–65	0.33	0.09	18.37	0.33	0.09	20.85	0.36	0.10	22.61	0.38	0.11	19.59
66–75	0.39 *	0.14	18.40	0.37 *	0.08	15.40	0.44 **	0.13	22.47	0.43	0.09	18.26
> 76	0.43 **	0.10	26.42	0.44 **^,##	0.09	15.34	0.50 **	0.10	29.68	0.58 **^,##	0.23	29.57
P value	< 0.001		0.211	< 0.001		0.195	< 0.001		0.341	< 0.001		0.155
P < 0.05 * vs. group 51–65, ^# vs. group 66–75; P < 0.01 ** vs. group 51–65, ^## vs. group 66–75

Table 2. Differences between tasks (base walk, motor, mental and combined task) are presented separately for three tested groups

	Groups	Motor vs. Base	Mental vs. Base	Combined vs. Base	Motor vs. Mental	Combined vs. Motor	Combined vs. Mental
CT	51-65	1.000	< 0.001	< 0.001	< 0.001	< 0.001	0.631
	66-75	1.000	< 0.001	< 0.001	< 0.001	< 0.001	1.000
	> 76	0.827	0.005	0.001	0.006	0.001	0.284
SL	51-65	< 0.001	< 0.001	< 0.001	0.053	< 0.001	< 0.001
	66-75	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001
	> 76	0.020	0.001	< 0.001	0.147	< 0.001	0.006
SWT	51-65	0.009	< 0.001	0.002	< 0.001	< 0.001	0.668
	66-75	0.238	< 0.001	< 0.001	< 0.001	< 0.001	1.000
	> 76	1.000	0.165	0.234	0.041	0.087	1.000
DST	51-65	1.000	0.015	0.010	0.035	< 0.001	1.000
	66-75	1.000	0.160	0.010	< 0.001	< 0.001	1.000
	> 76	1.000	0.467	0.017	0.507	0.021	0.327
CV CT	51-65	1.000	0.098	0.014	0.499	0.759	1.000
	66-75	1.000	0.021	0.114	0.027	0.316	0.948
	> 76	1.000	1.000	1.000	1.000	1.000	1.000
CV SL	51-65	0.994	0.008	0.029	< 0.001	0.001	1.000
	66-75	1.000	< 0.001	< 0.001	< 0.001	< 0.001	1.000
	> 76	1.000	< 0.001	< 0.001	0.001	0.001	1.000
CV SWT	51-65	1.000	1.000	1.000	0.781	1.000	1.000
	66-75	0.093	1.000	1.000	0.016	0.192	1.000
	> 76	1.000	0.139	0.726	0.027	0.580	1.000
CV DST	51-65	1.000	1.000	1.000	1.000	1.000	1.000
	66-75	0.557	0.812	1.000	0.010	1.000	0.717
	> 76	0.433	1.000	1.000	0.037	0.262	1.000

CT – cycle time, SL – stride length, SWT – swing time, DST – double support time

The results are depicted as p-values. Shaded fields indicate statistical significance (p < 0.05, Bonferroni correction).

Cycle time

Cycle time was significantly increased in the group > 76 years in comparison to the group 51–65 years in all test conditions, while in the group 66–75 years it was increased only during mental and combined tasks (Fig. 1, Table 1). In contrast to motor task which did not influence cycle time in all tested groups, mental and combined tasks increased cycle time (Table 2). In the group 51–65 years combined tasks increased CV values. In the group 66–75 years mental activity increased CV values compared with the base and motor conditions (Table 2).

Stride length

Stride length was significantly shorter in the group > 76 years in comparison to the group 51–65 years in all test conditions. However, in the group 66–75 years only mental and combined tasks shortened stride length in comparison to the youngest group (Fig. 1, Table 1). In all groups, motor, mental, and combined activity decreased stride length compared with stride length in basal conditions. Combined activity also significantly shortened stride length compared with motor and mental activity. Mental activity shortened the stride length compared to motor activity only in the group 66–75 years. Mental and combined activity significantly increased CV stride length in all groups (Table 2).

Swing time

A comparison of all three groups did not show a statistically significant difference in swing time (Fig. 1, Table 1). Mental and combined tasks increased swing time compared to the values in basal conditions in the groups 51–65 years and 66–75 years, while motor activity reduced swing time in the youngest group. The combined task increased swing time in the groups 51–65 years and 66–75 years. CV did not differ among groups under different test conditions, except that mental task increased CV swing time compared with motor task in the groups 66–75 years and > 76 years (Table 2).

Double support time

Double support time was increased in the group > 76 years compared to the group 51–65 years in all test conditions, as well as compared with the group 66–75 years under motor and combined tasks (Fig. 1, Table 1). Also, double support time was prolonged in the group 66–75 years compared to the group 51–65 years in basal conditions, as well as under motor and mental activities. The combined activity increased double support time compared to values in base and motor task conditions in all groups. CV double support time did not differ in different test conditions (Table 2).

Daily life activities require the simultaneous performance of multiple tasks, both motor and mental. With older age, the ability to divide attention and to perform multiple tasks simultaneously seems to be impaired [14, 19]. Particularly, when individuals have motor or cognitive impairments, it is more difficult for them to perform concurrent motor and cognitive tasks [20]. A hypothesis is that the two tasks influence each other and compete for cortical brain resources. Changes in movement, such as a slowing of movement speed, which are often defined as "dual task consumption", result from the involvement of cortical processes [11]. Gait changes which occur while performing another action can reveal impaired cognitive function in people with early Alzheimer's or Parkinson's disease. An impaired ability to divide cognitive resources between walking and an attention-demanding task put the patients at increased risk of falling [21]. Some changes in the walking mechanism, such as the reduction of step length and walking speed, while at the same time prolonging the phase of leaning on both legs can be mechanisms of adaptation of old people to the possibility of experiencing a fall [22].

Healthy young individuals also experience slowing of gait, as well as an impaired performance of an additional task, when they were asked to perform it while walking, suggesting that a complex activity such as walking relies on attention even in this population [23].

Mental task relies heavily on working memory capacity, and is thus directly dependent on executive functions [24]. Even in young individuals gait (with its parameters such as speed) is an automated process, which also requires minimal involvement of attention [13].

In our study, gait cycle time significantly increased in the eldest subjects over 76 years of age compared to the youngest subjects between 51–65 years of age in all testing conditions. Compared to the subjects between 66–75 years of age, in the eldest group gait cycle increased during performance of mental and combined tasks. CV was increased in the youngest group during the combined task, and in the middle group during the mental task.

Beauchet et al. [25] reported that the mean walking cycle duration in elderly people increased when they walked simultaneously performing arithmetic task (p = 0.005), but not the verbal fluency task, suggesting that gait speed during the dual task relies on the type of task presented to the subject. An increase in the CV of the gait cycle found while performing the backward counting task may be related to the competition of the motor task (walking) and executive functions (counting). Also, an increase in the gait cycle variability was found in elderly individuals while simultaneously carrying a filled glass and walking [26].

The duration of swinging with one leg, defined as the time during which the observed foot is in the air and is not in contact with the ground (swing time), did not differ between the groups of subjects in our study.

The stride length is the distance from contact with the foot (heel) of one foot to the contact of the same foot with the ground again [27]. Stride length was significantly shorter in the eldest group of subjects (> 76 years) compared to the youngest group (51–65 years) in all testing conditions. In the middle group of subjects (66–75 years old), only the mental and the combined task shortened the step length compared to the youngest group. In all groups, the additional task reduced step length compared to baseline gait, and in particular the combined task significantly reduced step length compared to motor and cognitive alone. The cognitive and combined task significantly increased the step length CV in all tested groups. Increased CV in step length, speed, or bipedal time is associated with the possibility of falling, but not to the same extent as the fear of falling [22]. High mean step length CV values are characteristic of moderate dementia, and high CV gait speed values are associated with moderate cognitive impairment [28].

Double support time increased in the group of subjects over 76 years of age compared to the group of 51–65 years of age during all test conditions, as well as compared to the group of 66–75 years of age during the motor and combined tasks. Also, the time of double support increased in the 66–75 years group compared to the 51–65 years group during the basic gait, as well as during the performance of motor and cognitive tasks. The combined activity increased the time of double support in all groups compared to the values during the basic gait, as well as during the performance of the motor task. CV did not differ significantly during the specified test conditions. The duration of the gait cycle is associated with an increase in the duration of double support, which can be interpreted as helping to reduce the attentional demands during the swing phase, and thus a lower risk for loss of balance. Changes in gait pattern while performing two tasks simultaneously may represent a strategy for maintaining gait efficiency [29].

With aging significant changes in gait parameters are observed, especially when gait is performed simultaneously with additional motor or cognitive task. Early detection of gait disorders can help identify elderly people at increased risk of falls and plan interventions to prevent negative consequences. Employing dual task paradigm during gait assessment in healthy elderly individuals may help identify those with cognitive impairment early, which is of utmost importance for tailoring clinical care interventions and enrolling patients to clinical trials with disease modifying drugs.

Competing interest

The authors have no competing interest or conflict of interest to report

Acknowledgment

This work has been supported by the Ministry of Science, Technological Development and Innovation of Republic of Serbia

Whittle M. Gait Analysis. 5th Ed. London, UK: Churchill Livingstone; 2012.
Scherder E, Eggermont L, Swaab D, et al. Gait in ageing and associated dementias; its relationship with cognition. Neurosci Biobehav Rev. 2007;31:485–97.
Callisaya ML, Blizzard L, Schmidt MD, McGinley JL, Srikanth VK. Ageing and gait variability-a population-based study of older people. Age Ageing. 2010;39:191-7.
Martin LK, Blizzard L, Wood GA, Srikanth V, Thomson R, Sanders ML, Callisaya LM. Cognitive Function, Gait, and Gait Variability in Older People: A Population-Based Study. J Gerontol A Biol Sci Med Sci. 2013;68:726-32.
Pirker W, Katzenschlager R. Gait disorders in adults and the elderly: A clinical guide. Wien Klin Wochenschr. 2017;129:81-95.
Ullmann G, Williams HG. The relationships among gait and mobility under single and dual task conditions in community-dwelling older adults. Aging Clin Exp Res. 2011;23:400-5.
Fritz S, Lusardi M. White paper: ’walking speed: the sixth vital sign’. J Ger Phys Ther. 2009;32:46–9.
Hausdorff JM, Yogev G, Springer S, Simon ES, Giladi N. Walking is more like catching than tapping: gait in the elderly as a complex cognitive task. Exp Brain Res. 2005;164:541-8.
Bahureksa L, Najafi B, Saleh A, Sabbagh M, Coon D, Mohler MJ, Schwenk M. The Impact of Mild Cognitive Impairment on Gait and Balance: A Systematic Review and Meta-Analysis of Studies Using Instrumented Assessment. Gerontology 2017;63:67-83.
Ble A, Volpato S, Zuliani G, Guralnik JM, Bandinelli S, Lauretani F, Bartali B, Maraldi C, Fellin R, Ferrucci L. Executive function correlates with walking speed in older persons: the InCHIANTI study. J Am Geriatr Soc. 2005;53:410-5.
Yogev-Seligmann G, Hausdorff JM, Giladi, N. The role of executive function and attention in gait. Mov Disord. 2008;23:329-42.
Savica R, Wennberg AM, Hagen C, Edwards K, Roberts RO, Hollman JH, Knopman DS, Boeve BF, Machulda MM, Petersen RC, Mielke MM. Comparison of Gait Parameters for Predicting Cognitive Decline: The Mayo Clinic Study of Aging. J Alzheimers Dis. 2017;55:559-67.
Beauchet O, Dubost V, Herrmann FR, Kressig RW. Stride-to-stride variability while backward counting among healthy young adults. J Neuroeng Rehabil. 2005a;11:2-26.
Priest AW, Salamon KB, Hollman JH. Age-related differences in dual task walking: a cross sectional study. J Neuroeng Rehabil 2008;14:5-29.
Hofheinz M, Schusterschitz C. Dual task interference in estimating the risk of falls and measuring change: a comparative, psychometric study of four measurements. Clin Rehab. 2010;24:831–42.
Hollman JH, Kovash MF, Kubik JJ, Linbo AR. Age-related differences in spatiotemporal markers of gait stability during dual task walking. Gait Posture 2007;26:113-9.
Radovanović S, Milićev M, Perić S, Basta I, Kostić V, Stević Z. Gait in amiotrophic lateral sclerosis: is gait pattern differently affected in spinal and bulbar onset of the disease during dual task walking? Amyotroph Lateral Scler Frontotemporal Degener. 2014;15:488–93.
Menz HB, Latt MD, Tiedemann A, Kwan MMS, Lord SR. Reliability of the GAITRite walkway system for the quantification of temporo-spatial parameters of gait in young and older people. Gait Posture. 2004;20:20–5.
Verhaeghen P, Steitz DW, Sliwinski MJ, Cerella J. Aging and dual-task performance: a meta-analysis. Psychol Aging. 2003;18:443-60.
Theill N, Martin M, Schumacher V, Bridenbaugh SA, Kressig RW. Simultaneously measuring gait and cognitive performance in cognitively healthy and cognitively impaired older adults: the Basel motor-cognition dual-task paradigm. J Am Geriatr Soc. 2011;59:1012-8.
Sheridan PL, Solomont J, Kowall N, Hausdorff JM: Influence of executive function on locomotor function: divided attention increases gait variability in Alzheimer's disease. J Am Geriatr Soc. 2003;51:1633-7.
Maki BE. Gait changes in older adults: predictors of falls or indicators of fear. J Am Geriatr Soc. 1997;45:313-20.
Leitner Y, Barak R, Giladi N, Peretz C, Eshel R, Gruendlinger L, Hausdorff JM. Gait in attention deficit hyperactivity disorder: effects of methylphenidate and dual tasking. J Neurol. 2007;254:1330-8.
Hittmair-Delazer M, Semenza C, Denses G: Concepts and facts in calculation. Brain 1994;117:715-28.
Beauchet O, Dubost V, Aminian K, Gonthier R, Kressig RW. Dual-task-related gait changes in the elderly: does the type of cognitive task matter? J Mot Behav. 2005b;37:259-64.
Grabiner PC, Biswas ST, Grabiner MD: Age-related changes in spatial and temporal gait variables. Arch Phys Med Rehabil. 2001;82:31-5.
Chambers HG, Sutherland DH. A practical guide to gait analysis. J Am Acad Orthop Surg. 2002;10:222-31.
Beauchet O, Blumen HM, Callisaya ML, De Cock AM, Kressig RW, Srikanth V, Steinmetz JP, Verghese J, Allali G. Spatiotemporal Gait Characteristics Associated with Cognitive Impairment: A Multicenter Cross-Sectional Study, the Intercontinental "Gait, cOgnitiOn & Decline" Initiative. Curr Alzheimer Res. 2018;15:273-82.
Woollacott M, Shumway-Cook A: Attention and the control of posture and gait: a review of an emerging area of research. Gait Posture 2002;16:1-14.

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Gait characteristics during dual task walking in elderly subjects of different age

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Abstract

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Experimental protocol

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