Introduction: Frailty is a common geriatric syndrome associated with decline in physiological reserve. While several digital biomarkers of daily physical activity (DPA) have been used in frailty assessment, the association between DPA variability and frailty is still not clear. The goal of this study was to determine the association between frailty and DPA variability. Methods: This is an observational cross-sectional study conducted between September 2012 and November 2013. Older adults (≥65 years), without any severe mobility disorder, and the ability to walk 10 m (with or without an assistive device) were eligible for the study. DPA including sitting, standing, walking, lying, and postural transition were recorded for 48 h continuously. DPA variability was analyzed from two perspectives: (i) DPA duration variability in terms of coefficient of variation (CoV) of sitting, standing, walking, and lying down durations; and (ii) DPA performance variability in terms of CoV of sit-to-stand (SiSt) and stand-to-sit (StSi) durations and stride time (i.e., slope of power spectral density – PSD). Results: Data was analyzed from 126 participants (44 non-frail, 60 pre-frail, and 22 frail). For DPA duration variability, CoV of lying and walking duration was significantly larger among non-frail compared to pre-frail and frail groups (p < 0.03, d = 0.89 ± 0.40). For DPA performance variability, StSi CoV and PSD slope were significantly smaller for non-frail compared to pre-frail and frail groups (p < 0.05, d = 0.78 ± 0.19). Conclusion: Lower DPA duration variability in pre-frail and frail groups may be attributed to the set daily routines frail older adults tend to follow, compared to variable physical activity routines of non-frail older adults. Higher DPA performance variability in the frail group may be attributed to reduced physiological capabilities toward walking for longer durations and the reduced muscle strength in the lower extremities, leading to incosistency in performing postural transitions.

1.
Mohler
MJ
,
Fain
MJ
,
Wertheimer
AM
,
Najafi
B
,
Nikolich-Žugich
J
.
The Frailty Syndrome: clinical measurements and basic underpinnings in humans and animals
.
Exp Gerontol
.
2014 Jun
54
6
13
.
2.
Fried
LP
,
Tangen
CM
,
Walston
J
,
Newman
AB
,
Hirsch
C
,
Gottdiener
J
.
Frailty in older adults: evidence for a phenotype
.
J Gerontol A Biol Sci Med Sci
.
2001 Mar
56
3
M146
56
.
3.
Abellan Van Kan
G
,
Rolland
Y
,
Bergman
H
,
Morley
JE
,
Kritchevsky
SB
,
Vellas
B
.
The I.A.N.A. task force on frailty assessment of older people in clinical practice
.
J Nutr Health Aging
.
2008 Jan
12
1
29
37
.
4.
Hausdorff
JM
,
Edelberg
HK
,
Mitchell
SL
,
Goldberger
AL
,
Wei
JY
.
Increased gait unsteadiness in community-dwelling elderly fallers
.
Arch Phys Med Rehabil
.
1997 Mar
78
3
278
83
.
5.
Grabiner
PC
,
Biswas
ST
,
Grabiner
MD
.
Age-related changes in spatial and temporal gait variables
.
Arch Phys Med Rehabil
.
2001 Jan
82
1
31
5
.
6.
Visser
M
,
Deeg
DJH
,
Lips
P
Longitudinal Aging Study Amsterdam
.
Low vitamin D and high parathyroid hormone levels as determinants of loss of muscle strength and muscle mass (sarcopenia): the Longitudinal Aging Study Amsterdam
.
J Clin Endocrinol Metab
.
2003
;
88
(
12
):
5766
72
.
7.
Martinikorena
I
,
Martínez-Ramírez
A
,
Gómez
M
,
Lecumberri
P
,
Casas-Herrero
A
,
Cadore
EL
.
Gait variability related to muscle quality and muscle power output in frail nonagenarian older adults
.
J Am Med Dir Assoc
.
2016 Feb
17
2
162
7
.
8.
Kosse
NM
,
Vuillerme
N
,
Hortobágyi
T
,
Lamoth
CJ
.
Multiple gait parameters derived from iPod accelerometry predict age-related gait changes
.
Gait Posture
.
2016 May
46
112
7
.
9.
Pradeep Kumar
D
,
Toosizadeh
N
,
Mohler
J
,
Ehsani
H
,
Mannier
C
,
Laksari
K
.
Sensor-based characterization of daily walking: a new paradigm in pre-frailty/frailty assessment
.
BMC Geriatr
.
2020
;
20
(
1
):
164
.
10.
Schwenk
M
,
Mohler
J
,
Wendel
C
,
D’Huyvetter
K
,
Fain
M
,
Taylor-Piliae
R
.
Wearable sensor-based in-home assessment of gait, balance, and physical activity for discrimination of frailty status: baseline results of the Arizona frailty cohort study
.
Gerontology
.
2015
;
61
(
3
):
258
67
.
11.
Mohler
MJ
,
Wendel
CS
,
Taylor-Piliae
RE
,
Toosizadeh
N
,
Najafi
B
.
Motor performance and physical activity as predictors of prospective falls in community-dwelling older adults by frailty level: application of wearable technology
.
Gerontology
.
2016
;
62
(
6
):
654
64
.
12.
Hempenius
L
,
Slaets
JPJ
,
Boelens
MAM
,
van Asselt
DZB
,
de Bock
GH
,
Wiggers
T
.
Inclusion of frail elderly patients in clinical trials: solutions to the problems
.
J Geriatr Oncol
.
2013 Jan
4
1
26
31
.
13.
Parvaneh
S
,
Mohler
J
,
Toosizadeh
N
,
Grewal
GS
,
Najafi
B
.
Postural transitions during activities of daily living could identify frailty status: application of wearable technology to identify frailty during unsupervised condition
.
Gerontology
.
2017 Aug
63
5
479
87
.
14.
Razjouyan
J
,
Naik
AD
,
Horstman
MJ
,
Kunik
ME
,
Amirmazaheri
M
,
Zhou
H
.
Wearable sensors and the assessment of frailty among vulnerable older adults: an observational cohort study
.
Sensors
.
2018
;
18
(
5
):
1336
.
15.
Razjouyan
J
,
Najafi
B
,
Horstman
M
,
Sharafkhaneh
A
,
Amirmazaheri
M
,
Zhou
H
.
Toward using wearables to remotely monitor cognitive frailty in community-living older adults: an observational study
.
Sensors
.
2020 Apr
20
8
2218
.
16.
Schwenk
M
,
Hauer
K
,
Zieschang
T
,
Englert
S
,
Mohler
J
,
Najafi
B
.
Sensor-Derived physical activity parameters can predict future falls in people with dementia
.
Gerontology
.
2014
;
60
(
6
):
483
92
.
17.
Peel
C
,
Sawyer Baker
P
,
Roth
DL
,
Brown
CJ
,
Bodner
EV
,
Allman
RM
.
Assessing mobility in older adults: the UAB study of aging life-space assessment
.
Phys Ther
.
2005 Oct
85
10
1008
119
.
18.
Portegijs
E
,
Rantakokko
M
,
Viljanen
A
,
Sipilä
S
,
Rantanen
T
.
Is frailty associated with life-space mobility and perceived autonomy in participation outdoors? A longitudinal study
.
Age Ageing
.
2016 Jul
45
4
550
3
.
19.
Pradeep Kumar
D
,
Wendel
C
,
Mohler
J
,
Laksari
K
,
Toosizadeh
N
.
Between-day repeatability of sensor-based in-home gait assessment among older adults: assessing the effect of frailty
.
Aging Clin Exp Res
.
2020 Sep
33
6
1529
37
.
20.
Hills
AP
,
Hennig
EM
,
Byrne
NM
,
Steele
JR
.
The biomechanics of adiposity: structural and functional limitations of obesity and implications for movement
.
Obes Rev
.
2002 Feb
3
1
35
43
.
21.
Najafi
B
,
Aminian
K
,
Paraschiv-Ionescu
A
,
Loew
F
,
Büla
CJ
,
Robert
P
.
Ambulatory system for human motion analysis using a kinematic sensor: monitoring of daily physical activity in the elderly
.
IEEE Trans Biomed Eng
.
2003 Jun
50
6
711
23
.
22.
Najafi
B
,
Aminian
K
,
Loew
F
,
Blanc
Y
,
Robert
PA
.
Measurement of stand-sit and sit-stand transitions using a miniature gyroscope and its application in fall risk evaluation in the elderly
.
IEEE Trans Biomed Eng
.
2002 Aug
49
8
843
51
.
23.
Najafi
B
,
Armstrong
DG
,
Mohler
J
.
Novel wearable technology for assessing spontaneous daily physical activity and risk of falling in older adults with diabetes
.
J Diabetes Sci Technol
.
2013
;
7
(
5
):
1147
60
.
24.
Bruin
ED
,
Najafi
B
,
Murer
K
,
Uebelhart
D
,
Aminian
K
.
Quantification of everyday motor function in a geriatric population
.
J Rehabil Res Dev
.
2007
;
44
(
3
):
417
28
.
25.
Folstein
MF
,
Folstein
SE
,
McHugh
PR
.
Mini-mental state
.
J Psychiatr Res
.
1975 Nov
12
3
189
98
.
26.
World Medical Association
.
World Medical Association Declaration of Helsinki: ethical principles for medical research involving human subjectsi
.
JAMA
.
2013 Nov
310
20
2191
4
.
27.
Yardley
L
,
Beyer
N
,
Hauer
K
,
Kempen
G
,
Piot-Ziegler
C
,
Todd
C
.
Development and initial validation of the falls efficacy scale-international (FES-I)
.
Age Ageing
.
2005 Nov
34
6
614
9
.
28.
Wachowiak
MP
,
Rash
GS
,
Quesada
PM
,
Desoky
AH
.
Wavelet-based noise removal for biomechanical signals: a comparative study
.
IEEE Trans Biomed Eng
.
2000
;
47
(
3
):
360
8
.
29.
Sekine
M
,
Tamura
T
,
Ogawa
M
,
Togawa
T
,
Fukui
Y
Classification of acceleration waveform in a continuous walking record.
IEEE
2002
. p.
1523
6
.
30.
Taffett
GE
.
Physiology of aging
.
Geriatric medicine
New York
Springer-Verlag
2003
. p.
27
35
.
31.
Ferrucci
L
,
Cavazzini
C
,
Corsi
A
,
Bartali
B
,
Russo
CR
,
Lauretani
F
.
Biomarkers of frailty in older persons
.
J endocrinological Invest
.
2002 Jan
25
10 Suppl
10
5
.
32.
Xue
QL
,
Fried
LP
,
Glass
TA
,
Laffan
A
,
Chaves
PHM
.
Life-space constriction, development of frailty, and the competing risk of mortality the women’s health and aging study I
.
Am J Epidemiol
.
2007
;
167
(
2
):
240
8
.
33.
Bohannon
RW
.
Sit-to-stand test for measuring performance of lower extremity muscles
.
Percept Mot Skills
.
1995
;
80
(
1
):
163
6
.
34.
Jones
CJ
,
Rikli
RE
,
Beam
WC
.
A 30-s chair-stand test as a measure of lower body strength in community-residing older adults
.
Res Q Exerc Sport
.
1999 Jan
70
2
113
9
.
35.
Ganea
R
,
Paraschiv-Ionescu
A
,
Büla
C
,
Rochat
S
,
Aminian
K
.
Multi-parametric evaluation of sit-to-stand and stand-to-sit transitions in elderly people
.
Med Eng Phys
.
2011
;
33
(
9
):
1086
93
.
36.
Orter
S
,
Ravi
DK
,
Singh
NB
,
Vogl
F
,
Taylor
WR
,
König Ignasiak
N
.
A method to concatenate multiple short time series for evaluating dynamic behaviour during walking
.
PLoS One
.
2019
;
14
(
6
):
e0218594
.
37.
JM
Hausdorff
,
DA
Rios
,
HK
Edelberg
.
Gait variability and fall risk in community-living older adults: a 1-year prospective study
.
Arch Phys Med Rehabil
.
2001
;
82
(
8
):
1050
6
.
38.
Hausdorff
JM
.
Gait dynamics, fractals and falls: finding meaning in the stride-to-stride fluctuations of human walking
.
Hum Mov Sci
.
2007 Aug
26
4
555
89
.
39.
Arcelus
A
,
Herry
CL
,
Goubran
RA
,
Knoefel
F
,
Sveistrup
H
,
Bilodeau
M
.
Determination of sit-to-stand transfer duration using bed and floor pressure sequences
.
IEEE Trans Biomed Eng
.
2009
;
56
(
10
):
2485
92
.
40.
Regterschot
GRH
,
Zhang
W
,
Baldus
H
,
Stevens
M
,
Zijlstra
W
.
Test–retest reliability of sensor-based sit-to-stand measures in young and older adults
.
Gait Posture
.
2014 May
40
1
220
4
.
41.
Bidargaddi
N
,
Klingbeil
L
,
Sarela
A
,
Boyle
J
,
Cheung
V
,
Yelland
C
.
Wavelet based approach for posture transition estimation using a waist worn accelerometer
.
Annu Int Conf IEEE Eng Med Biol Soc
.
2007
;
2007
:
1884
7
.
42.
Jeon
W
,
Whitall
J
,
Griffin
L
,
Westlake
KP
.
Trunk kinematics and muscle activation patterns during stand-to-sit movement and the relationship with postural stability in aging
.
Gait Posture
.
2021 May
86
292
8
.
43.
Galán-Mercant
A
,
Cuesta-Vargas
AI
.
Differences in trunk accelerometry between frail and nonfrail elderly persons in sit-to-stand and stand-to-sit transitions based on a mobile inertial sensor
.
JMIR mHealth uHealth
.
2013 Jul
1
2
e21
.
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