BJMB
Brazilian Journal of Motor Behavior
Special issue:
Effects of aging on locomotor patterns
!
Costa et al.
2022
VOL.16
N.5
352 of 361
Dual-task performance in seniors with mild cognitive impairment and Alzheimer’s disease:
a longitudinal study
DANIELLE C. P. S. COSTA
1
| JULIANA H. ANSAI
2
| LAURA M. MELO
1
| ANA CAROLINA V. FERREIRA
1
| PAULO G.
ROSSI
1
| FRANCISCO A. C. VALE
3
| LARISSA P. ANDRADE
1
1
Department of Physical Therapy, Federal University of São Carlos, São Carlos, SP, Brazil.
2
Department of Gerontology, Federal University of São Carlos, São Carlos, SP, Brazil.
3
Department of Medicine, Federal University of São Carlos, São Carlos, SP, Brazil.
Correspondence to:!Larissa Pires de Andrade, Department of Physical Therapy, Federal University of São Carlos, Rodovia Washington Luiz, km 235, Zipcode 13565-905,
+55 16 3351-8704
email: larissa.andrade@ufscar.br
https://doi.org/10.20338/bjmb.v16i5.309
HIGHLIGTHS
• Alzheimer's disease has an impact on the
ability of carrying out a dual task.
• Dual task performance worsens over time in
older adults with Alzheimer’s disease.
• Time, steps and cadence worsened with time
in older adults with Alzheimer’s disease.
• We suggest that walking and using the phone
is an effective dual task assessment.
ABBREVIATIONS
AD Alzheimer`s disease
CDR Clinical Dementia Rating
CMT cognitive-motor test
DSM-IV-TR Diagnostic and Statistical Manual
of Mental Disorders
DT Dual task
MCI Mild cognitive impairment
MMSE Mini Mental State Exam
PrC Preserved cognition
T1 Initial moment
T2 After 32 months
TUGT Timed up and go test
UFSCar Universidade Federal de São
Carlos
PUBLICATION DATA
Received 07 06 2022
Accepted 02 12 2022
Published 15 12 2022
BACKGROUND: Motor performance in older adults with cognitive impairment is worse under dual task
conditions, increasing the risk of falls. However, there is a lack of studies that analyze this performance over
time in people with different cognitive profiles.
AIM: This study aimed to compare the performance of an isolated task and a dual task in people with preserved
cognition (PrC), with mild cognitive impairment (MCI) and Alzheimer`s disease (AD).
METHOD: Data were collected on two occasions (T1 and T2), thirty-two months apart. Participants (n=51) were
separated between groups: PrC (n=22), MCI (n=19) and AD (n=10). They were analyzed in three situations: 1)
isolated motor task - Timed up and go test (TUGT); 2) cognitive-motor test (CMT)– dialing on a phone; 3) dual
task (DT). To compare the performance of the dual task between the groups, delta was calculated and the
ANCOVA test was applied.
RESULTS: Although the cost of the dual task was not significantly different over time in any group, we found
increases in the time required to complete the TUGT (p<0.01) and TUGT-DT (p>0.01) after 32 months in the AD
group and a reduction in time in the PrC and MCI groups. A greater number of steps in the TUGT-DT (p<0.01)
and an increase in cadence in the TUGT (p = 0.01) and TUGT-DT (p<0.01) were also found in the AD group.
CONCLUSION: We suggest that a more functional task, such as walking while typing on the phone, may be
considered a more sensitive way of assessing older adults with AD.
KEYWORDS: Alzheimer’s disease | Dual task | Cognitive Impairment | Older adults | Timed Up and Go test
INTRODUCTION
Due to the increase in life expectancy, pathologies inherent to aging, including the
possibility of neurodegenerative diseases, such as some types of public health, have
become an important public health problem. This is because dementia is considered one
of the main causes of disability in adult life, triggering high costs of assistance to the
burden of family members and relatives. However, it presents a challenge for research to
understand the trajectory of this disease over time,and thus be able to guide health actions
through the most effective approaches and interventions
1
. Alzheimer’s disease (AD) is a
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Brazilian(Journal(of(Motor(Behavior(
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Costa et al.
2022
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N.5
353 of 361
Special issue:
Effects of aging on locomotor patterns
progressive, irreversible condition that exerts a negative impact on cognitive functions and
the performance of activities of daily living
2
. Mild cognitive impairment (MCI) is another
condition that has been investigated in the aging process and constitutes a transition
phase between physiological neuronal loss in the natural aging process and dementia
3
.
Older adults with cognitive impairment have a poorer performance in dual tasks
compared to those with preserved cognition (PrC)
4
. Cross-sectional studies comparing
older adults with PrC to those with some type of cognitive impairment have reported a
negative impact on gait during a dual task in the latter group
5,6,7,8
. These changes may be
explained by a central interference caused by the increase in brain activity during the
simultaneous performance of two tasks and the limitation of attentional resources
9
, which
may decrease performance in one or both tasks and considerably increase the risk of falls
10
.
Although the studies cited have contributed knowledge on dual task performance,
as well as motor performance among older adults with MCI and AD, there is a need for
longitudinal studies to investigate the dual task performance of older adults in different
cognitive status conditions.
Therefore, the aim of the present longitudinal study was to compare the
performance on an isolated task and dual task in older adults with PrC, MCI and mild AD.
We tested the hypothesis that, over time, older adults with PrC, with MCI and AD would
present significant differences when performing the dual task, with worse performance in
older adults who had greater cognitive impairment.
METHODS
Participants
The present study is a sub-study of the longitudinal project called the“Brazilian
longitudinal study about motor alterations in older people with cognitive disorders
(BLSMotorCD)”. This study received approval from the human research ethics committee
(certificate number: 72774317.7.0000.5504) and all the participants or their caregivers
signed a statement of informed consent. At the initial moment (T1), 118 older adults were
recruited, who were evaluated and allocated into three groups: PrC, MCI and AD.
AD and MCI were diagnosed according to the Diagnostic and Statistical Manual of
Mental Disorders (DSM-IV-TR)
11
, including assessments of the Clinical Dementia Rating
(CDR)
12
and Mini Mental State Examination (MMSE)
13
. The confirmation of the diagnosis
was performed at the Department of Medicine at the Universidade Federal de São Carlos
(UFSCar) by a trained team coordinated by Dr. FACV at the Behavioral Cognitive
Neurology Clinic.
After 32 months (T2)
10
, one hundred and eighteen older adults were contacted
again by the evaluators. Of these, fifty-one individuals participated in T2 (10 with AD, 19
with MCI and 22 with PrC). Reasons for discontinuation during the study period were
withdrawal (n = 23), loss of contact (n = 12), death (n = 11) and exclusion
(bedridden/restricted to a wheelchair: n = 18; severe behavioral disorder: n = 3).
Procedures
The two evaluators at T1
5
and T2 were blinded to the allocation of volunteers in
the different groups and underwent a reliability analysis. The inter-examiner reliability test
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Costa et al.
2022
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N.5
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Special issue:
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was performed on the same day for both evaluators and the intra-examiner was applied
with an interval of seven days from the first test. Nineteen randomly selected types of
footage of TUGT evaluations were used. Only the time variable was computed for the
reliability test. All footage used was from cognitively preserved individuals or diagnosed
with MCI. Each examiner evaluated the same videos in the two periods described
(intraclass correlation coefficient = 1).
After analyzing the patient history, sociodemographic variables, the Geriatric
Depression Scale was applied to determine symptoms of depression
14
and the Minnesota
Questionnaire was administered to measure the level of physical activity
15
. Then, the
participants performed the following tasks twice, one considered as familiarization and the
second for the test:
Timed Up and Go test (TUGT)
The version of the TUGT adapted for older adults with cognitive impairment was
used
16
. The following standard commands were given: “Get ready, go. Stand up, walk, go
around the cone and sit down”
16
. The timer was started when the individual left the chair
and stopped when the subject leaned back again. Cadence was calculated by the number
of steps divided by the running time (Figure 1). The course performed in less than 12.47
seconds has less risk of falling, while if the time is longer than 12.47 seconds, it represents
a greater risk of falls
17
.
Figure 1.!Illustration of commands while applying the TUGT. Source: the author.
Cognitive-motor task (CMT)
For the Cognitive-motor task, the participant was instructed to type a sequence of
eight numbers on a cell phone, a common task nowadays that requires preserved
cognition functions (such as attention and visuospatial notion, for example), as well as the
motor function for typing. A randomly selected card was attached to the screen of the
telephone and the participant received the following instructions: “Get ready, go. Pick up
the telephone, type the eight numbers on the card and put the phone back on the table”
5