Key words
early rehabilitation - exercise therapy - Medical rehabilitation
Schlüsselwörter
Frührehabilitation - Bewegungstherapie - Rehabilitation
Introduction
Stroke was known as the leading cause of adult disability and resulted in great social burden
[1]
[2]. Approximately a third of stroke patients suffered
from the recurrence of stroke, and 75% of them had cardiac disease [3]
[4]. Many stroke survivors wanted to return to independent
living and to achieve a good quality of life [5]. The
onset of stroke was sudden, and it was ill-prepared to deal with the sequelae for the individual
and the family [6]
[7].
It was urgent and important to develop practical interventions in order to reduce disability
levels and prevent stroke recurrence and cardiovascular disease [8]. Stroke recurrence was influenced by various modifiable metabolic risk factors such
as impaired glucose control, dyslipidemia, hypertension, obesity, and low cardiorespiratory
fitness, which resulted in the damage of the structure and function of blood vessels [9]
[10]
[11]
[12]. The increase in physical activity was reported to be
the inexpensive, safe, and effective method of improving metabolic risk factors and vascular
control [13]
[14]. Structured community exercise resulted in short- and
long-term functional benefits post stroke [15]. Some
randomized controlled trials (RCTs) demonstrated that community exercise could significantly
increase 6-Minute walk distance, walking speed and improve balance in stroke patients [16]
[17].
In contrast to this promising finding, however, some relevant RCTs showed that community
exercise had no influence on walking speed, muscle strength and mental quality of life for
stroke patients [17]
[18]. Considering these inconsistent effects, we therefore
conducted a systematic review and meta-analysis of RCTs to evaluate the effectiveness of
community exercise in patients with stroke.
Materials and methods
This systematic review and meta-analysis were conducted according to the guidance of the
Preferred Reporting Items for Systematic Reviews and Meta-analysis statement [19] and the Cochrane Handbook for Systematic Reviews of
Interventions [20]. All analyses were based on previous
published studies, thus no ethical approval and patient consent were required.
Literature search and selection criteria
PubMed, EMbase, Web of science, EBSCO, and the Cochrane library were systematically searched
from inception to July 2017, with the following keywords: community exercise, and stroke. No
limitation was enhanced. To include additional eligible studies, the reference lists of
retrieved studies and relevant reviews were also hand-searched and the process above was
performed repeatedly until no further article was identified. Conference abstracts meeting the
inclusion criteria were also included.
The inclusion criteria were as follows: study population, patients with stroke; intervention,
community exercise; control, usual care; outcome measure, 6-Minute walk test and walking speed;
and study design, RCT.
Data extraction and outcome measures
The following information was extracted for the included RCTs: first author, publication
year, sample size, baseline characteristics of patients, community exercise, control, study
design, 6-Minute walk test, walking speed, Berg Balance Scale, muscle strength and mental
quality of life. The author would be contacted to acquire the data when necessary.
The primary outcomes were 6-Minute walk test and walking speed. Secondary outcomes included
Berg Balance Scale, muscle strength and mental quality of life. 6-Minute walk test served as a
reliable method to assess walking performance in individuals with stroke through recording the
distance walked in 6 min [21]. Berg Balance Scale
(maximal score=56) was applied to assess the functional balance in older adults [22].
Quality assessment in individual studies
The Jadad Scale was used to evaluate the methodological quality of each RCT included in this
meta-analysis [23]. This scale consisted of 3 evaluation
elements: randomization (0–2 points), blinding (0–2 points), dropouts and
withdrawals (0–1 points). One point would be allocated to each element if they have
been mentioned in article, and another one point would be given if the methods of randomization
and/or blinding had been detailedly and appropriately described. If methods of
randomization and/or blinding were inappropriate, or dropouts and withdrawals had not
been recorded, then one point was deducted. The score of Jadad Scale varied from 0 to 5 points.
An article with Jadad score≤2 was considered to be of low quality. If the Jadad
score≥3, the study was thought to be of high quality [24].
Statistical analysis
Standard Mean differences (Std. MDs) with 95% confidence intervals (CIs) for
continuous outcomes (6-Minute walk test, walking speed, Berg Balance Scale, muscle strength and
mental quality of life) were used to estimate the pooled effects. All meta-analyses were
performed using random-effects models with DerSimonian and Laird weights. Heterogeneity was
tested using the Cochran Q statistic (p<0.1) and quantified with the I2
statistic, which described the variation of effect size that was attributable to heterogeneity
across studies. An I2 value greater than 50% indicated significant
heterogeneity. Sensitivity analysis was performed to detect the influence of a single study on
the overall estimate via omitting one study in turn when necessary. Owing to the limited number
(<10) of included studies, publication bias was not assessed. P<0.05 in
2-tailed tests was considered statistically significant. All statistical analyses were
performed with Review Manager Version 5.3 (The Cochrane Collaboration, Software Update, Oxford,
UK).
Results
Literature search, study characteristics and quality assessment
The flow chart for the selection process and detailed identification was presented in [Fig. 1]. 498 publications were identified through the
initial search of databases. Ultimately, 4 RCTs were included in the meta-analysis [16]
[17]
[18]
[25].
Fig. 1 Flow diagram of study searching and selection process.
The baseline characteristics of the 4 eligible RCTs in the meta-analysis were summarized in
[Table 1]. The 4 studies were published between 2005
and 2015, and sample sizes ranged from 40 to 232 with a total of 497. There were no significant
difference of age, time since stroke and Mini Mental State Examination between community
exercise group and control group at baseline.
Table 1 Characteristics of included studies.
|
NO.
|
Author
|
Community exercise group
|
Control group
|
Jada scores
|
|
Number
|
Age (years)
|
Male (n)
|
Hemorrhagic stroke/Ischemic stroke (n)
|
Time since stroke
|
Mini Mental State Examination
|
Number
|
Age (years)
|
Male (n)
|
Hemorrhagic stroke/Ischemic stroke (n)
|
Time since stroke
|
Mini Mental State Examination
|
|
1
|
Moore 2015
|
20
|
68±8
|
18
|
1/19
|
21±34 months
|
28±2
|
20
|
70±11
|
16
|
2/18
|
16±12 months
|
29±1
|
4
|
|
2
|
Dean 2012
|
76
|
66.7±14.3
|
38
|
–
|
6.7±6.7 years
|
27±3
|
75
|
67.5±10.2
|
40
|
–
|
5.2±5.4 years
|
27±3
|
5
|
|
3
|
Harrington 2010
|
119
|
70±10.2
|
67
|
–
|
–
|
–
|
124
|
71±10.5
|
65
|
–
|
–
|
–
|
3
|
|
4
|
Pang 2005
|
32
|
65.8±9.1
|
19
|
14/18
|
–
|
27.6±2.3
|
31
|
64.7±8.4
|
18
|
12/19
|
–
|
28.2±1.9
|
4
|
Among the 4 RCTs, 3 studies reported the 6-Minute walk test [16]
[17]
[18], 2 studies reported the walking speed [16]
[17], 2 studies reported the Berg Balance Scale [16]
[18], 2 studies reported the muscle strength [16]
[18] and 2 studies reported the mental quality of life
[16]
[17]. Jadad scores of the 4 included studies varied from
3 to 5, and all 4 studies were considered to be high-quality ones according to quality
assessment.
Primary outcome: 6-Minute walk test, and walking speed
These 2 outcome data were analyzed with the random-effects model. In [Fig. 2], “Dean 2012” represented the data of
6-Minute walk test among faster walker of stroke patients, and “Dean
2012+” represented the data of 6-Minute walk test among slower walker of stroke
patients [17]. Similarly, “Dean 2012” and
“Dean 2012+” represented the data of walking speed in the same study in
[Fig. 3]. The pooled estimate of the 3 included RCTs
suggested that compared to control group, community exercise intervention was associated with a
significantly increased 6-Minute walk distance (Std. mean difference=0.48; 95%
CI=0.22–0.74; P=0.0003), with no heterogeneity among the studies
(I2=0%, heterogeneity P=0.86, [Fig. 2]). Consistently, community exercise could
significantly improve walking speed (Std. mean difference=0.40; 95%
CI=0.10–0.70; P=0.009) compared to control group, with no heterogeneity
among the studies (I2=0%, heterogeneity P=0.66, [Fig. 3]).
Fig. 2 Forest plot for the meta-analysis of 6-Minute walk test (m).
Fig. 3 Forest plot for the meta-analysis of walking speed (m/s).
Sensitivity analysis
No heterogeneity was observed among the included studies for the 6-Minute walk test, and
walking speed. Thus, we did not perform sensitivity analysis by omitting one study in each turn
or perform subgroup analysis to detect the source of heterogeneity.
Secondary outcomes
Compared with control intervention in stroke patients, community exercise showed no
substantial influence on Berg Balance Scale (Std. mean difference=0.39; 95%
CI=−0.29 to 1.07; P=0.26; [Fig.
4]), muscle strength (Std. mean difference=0.05; 95%
CI=−0.34 to 0.43; P=0.82; [Fig.
5]) and mental quality of life (Std. mean difference=0.04; 95%
CI=−0.25 to 0.34; P=0.77; [Fig.
6]).
Fig. 4 Forest plot for the meta-analysis of Berg Balance Scale.
Fig. 5 Forest plot for the meta-analysis of muscle strength (N).
Fig. 6 Forest plot for the meta-analysis of mental quality of life.
Discussion
In our meta-analysis, community exercise led to clinically significant improvements in
6-Minute walk test, and walking speed in stroke patients, but showed no substantial effect on
Berg Balance Scale, muscle strength or mental quality of life. To our knowledge, this was the
first meta-analysis to investigate the efficacy of community-based exercise in stroke patients.
Additionally, quality of life increased in terms of mood and physical functioning [26]
[27]. Improved cognition was revealed after community
exercise, which was in line with previous interventional studies in healthy individuals [16]
[28]. No participants experienced any adverse events in
the included RCTs.
Community-based exercise therapy was reported to be a feasible method of modifying metabolic
risk factors [29]
[30]. A 23% increase (0.3 mmol/L)
of high-density lipoprotein cholesterol (HDL-C) was revealed after exercise.
0.06 mmol/L increase of HDL-C led to a 6% reduction in coronary heart
disease, and 75% of stroke survivors had cardiac disease [31]
[32]
[33]. However, exercise showed no influence on lipid
profile, cholesterol and low-density lipoprotein cholesterol (LDL-C) [34]
[35].
Previous study showed that community-based exercise might showed significant influence on
glucose control in type 2 diabetes mellitus (T2DM) or impaired glucose tolerance (IGT) patients,
but had no substantial effect on glucose control in patients without T2DM or IGT. Possibly
because study participants had adequate glucose control [36]. The brain imaging data demonstrated that in stroke patients, medial temporal lobe
tissue structure was maintained, and regional blood flow was increased after exercise
intervention. In contrast, significant atrophy of the medial temporal lobe was found in the
control group. This area with the increase in regional blood flow after exercise might be
associated with cognition, indicating that exercise was a possible means of ameliorating atrophy
post-stroke and improving long-term cognition [16]
[37]
[38].
Exercise therapy was reported to produce significant short-term improvements in
cardiorespiratory fitness (the increase by 17%, 3 mL/kg/min),
lipid profile, and blood pressure. These could potentially enable individuals with stroke to
sustain light activities of daily living and undertake more vigorous activities [39]
[40]. The reduction in diastolic blood pressure of
4 mm Hg could reduce the relative risk of recurrent stroke by 28%, and exercise
reduced diastolic blood pressure by 3 mm Hg [41]
[42].
Several limitations should be taken into account. Firstly, our analysis was based on 4 RCTs
but 2 of them have a relatively small sample size (n<100). Overestimation of the
treatment effect was more likely in smaller trials compared with larger samples. More clinical
trials with large sample were needed to explore this issue. Stroke participants only had
mild-moderate deficit in included RCTs, and the influence of community exercise on stroke
patients with serious deficit was not clear. It was difficult to perform subgroup analysis based
on hemorrhagic stroke and ischemic stroke which might have different pooling results. Finally,
some unpublished and missing data might lead bias to the pooled effect.
Conclusion
Community exercise showed an important ability to improve 6-Minute walk test, and walking
speed in stoke patients. Community exercise was recommended to be administrated for stoke.
