Upper limb exercise training for COPD
Abstract
This is a protocol for a Cochrane Review (Intervention). The objectives are as follows:
To determine the effects of upper limb training (endurance or strength training, or both) on symptoms of dyspnoea and health‐related quality of life in people with COPD.
Background
Description of the condition
Chronic obstructive pulmonary disease (COPD) is a progressive disease state characterised by persistent airflow limitation and an enhanced chronic inflammatory response in the airways and lungs to noxious particles or gases (Vestbo 2013). The prevalence of moderate to very severe COPD varies by country, but it has been reported at between 4% and 17% (Buist 2007; Toelle 2013). COPD is a major cause of morbidity, mortality, and increased healthcare costs globally (Chapman 2006). People with COPD often have reduced functional capacity and are physically inactive, which has been associated with increased healthcare utilisation (Garcia‐Aymerich 2006). People with COPD also often experience difficulty with upper limb exercise (Celli 1986; Criner 1988; McKeough 2003) and perform upper limb activities at a lower intensity than their healthy counterparts (Meijer 2014). Difficulty with upper limb exercise in people with COPD is partially due to alterations in the mechanics of breathing associated with the disease, such that the muscles required for the upper limb exercise are also required for breathing (Criner 1988). Consequently, when performing activities using their upper limbs, people with COPD can experience breathlessness and early cessation of the task. Given that most daily living activities require the use of the arms, breathlessness and the early cessation of upper limb activities pose a challenge to people with COPD.
Description of the intervention
Pulmonary rehabilitation, a program of exercise training, education, and behaviour support, is one management strategy that has strong evidence for improving functional exercise capacity and health‐related quality of life in people with COPD (Lacasse 2006). The exercise training component typically incorporates both lower and upper limb training. The types of upper limb training performed in a conventional pulmonary rehabilitation program consist of both aerobic training, which can be further categorised as supported training (for example arm cycle ergometer training) or unsupported training (for example lifting a dowel), as well as strength training (for example resistance machines, free weights, or resistance bands).
How the intervention might work
The upper limb training component of pulmonary rehabilitation for people with COPD has been shown to have effects specific to the type of training performed. Upper limb strength training has been shown to increase upper limb strength (O'Shea 2004; Janaudis‐Ferreira 2011), while upper limb aerobic training, whether performed supported, unsupported, or as a combined supported/unsupported protocol, has been shown to increase upper limb endurance capacity (Martinez 1993; Holland 2004; McKeough 2012). The possible mechanisms for arm training improving arm exercise capacity have been discussed previously (Janaudis‐Ferreira 2009) and include physiological improvements at the muscle level, such as an increased oxidative capacity as is typical of exercise training effects for the lower limb muscles in COPD (Maltais 1996); improved tolerance to symptoms during arm activity (Gigliotti 2005); and improved force‐generating capacity of the muscles in line with any increases in muscle strength from the upper limb training.
Why it is important to do this review
The latest American Thoracic Society/European Respiratory Society statement on pulmonary rehabilitation recommends that upper limb training be performed in programs given the evidence for improvements to upper limb function (Spruit 2013), but the statement also indicates that the optimal form of upper limb training remains to be determined. It is also unclear whether the gains to upper limb function translate to improvements in other important health outcomes, such as symptoms of dyspnoea and health‐related quality of life. Previous reviews of upper limb training have been done (Costi 2009; Ennis 2009; Janaudis‐Ferreira 2009), but only one review included some meta‐analysis of outcomes (Ennis 2009). Since the publication of these reviews, there have been a number of other randomised controlled trials investigating the effects of upper limb training in COPD (Costi 2009a; Janaudis‐Ferreira 2011; McKeough 2012). This review will analyse randomised controlled trials to determine the effects of upper limb training on symptoms of dyspnoea, health‐related quality of life, and measures of upper limb function in people with COPD. This review will provide the evidence base for the effectiveness, or otherwise, of upper limb training and may assist in determining the optimal prescription of upper limb training for people with COPD.
Objectives
To determine the effects of upper limb training (endurance or strength training, or both) on symptoms of dyspnoea and health‐related quality of life in people with COPD.
Methods
Criteria for considering studies for this review
Types of studies
We will include randomised controlled trials (RCTs) in which upper limb exercise training of at least four weeks' duration is compared to no training, lower limb training, or another form of arm training.
Types of participants
We will include adults with a clinical diagnosis of COPD, diagnosed according to the investigators' definition. Participants may be of any age or disease severity. Participants' COPD should be stable (that is optimal and stable respiratory medications with no exacerbation or hospital admission within the previous month), although oxygen supplementation during training may be used.
Types of interventions
We will include studies examining upper limb exercise training of at least four weeks duration, as this will ensure the 20 or more sessions of training that is recommended in pulmonary rehabilitation programs (Nici 2006). The upper limb exercise training may include endurance training (supported or unsupported training), strength training, or a combination of strength and endurance training. The upper limb training may be in addition to a prescribed lower limb training program. We will include inpatient, outpatient, and home‐based training programs. We will record the precise nature of the training (intensity, frequency, duration, type) wherever possible.
The upper limb training group/s will be compared to either a control group of no training, lower limb training, or another form of upper limb training (this allows for a comparison of supported versus unsupported upper limb training or upper limb endurance versus upper limb strength training, for example).
We will structure the comparisons as follows:
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Upper limb training only versus no training (i.e. usual care only) or sham intervention
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Combined upper limb training and lower limb training versus lower limb training alone
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Upper limb training versus another type of upper limb training intervention (with or without lower limb training in both groups)
Types of outcome measures
Primary outcomes
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Symptoms of dyspnoea measured using dyspnoea scores from a respiratory‐specific quality‐of‐life questionnaire (e.g. dyspnoea from the chronic respiratory disease questionnaire).
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Health‐related quality of life measured using total scores from generic or respiratory‐specific quality‐of‐life questionnaires.
Secondary outcomes
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Peak upper limb exercise capacity measured from an upper limb peak exercise test.
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Endurance upper limb exercise capacity measured from an upper limb endurance test.
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Upper limb strength measured using hand‐held dynamometry or upper limb resistance machines (e.g. 1 RM).
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Respiratory muscle strength measured from a pressure gauge (e.g. maximal inspiratory and expiratory mouth pressures or maximal sniff nasal inspiratory pressure).
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Physical activity level from subjective measures (e.g. activity diaries, questionnaires) or objective measures (e.g. activity monitoring devices such as pedometers, accelerometers, multi‐sensor devices).
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Activities of Daily Living (ADL) function measured as the time or movement intensity during the performance of activities of daily living.
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Psychological status measured from generic psychological questionnaires or scales (e.g. Hospital Anxiety and Depression Scale).
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Healthcare utilisation recorded as hospitalisation and/or length of stay.
We will review primary and secondary outcomes at baseline and immediately following the upper limb exercise training or control intervention. If outcomes are also measured in the long term (for example 12 months after training has been completed), this will also be reviewed. We have chosen all outcomes as measures that are clinically relevant and that may be altered by an upper limb exercise training intervention.
Search methods for identification of studies
Electronic searches
We will identify trials from the Cochrane Airways Group Specialised Register (CAGR), which is maintained by the Trials Search Co‐ordinator for the Group. The CAGR contains trial reports identified through systematic searches of bibliographic databases including the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, CINAHL, AMED, and PsycINFO, and handsearching of respiratory journals and meeting abstracts (please see Appendix 1 for further details). We will search all records in the CAGR using the search strategy in Appendix 2.
We will also conduct a search of ClinicalTrials.gov (www.ClinicalTrials.gov) and the World Health Organization trials portal (www.who.int/ictrp/en/). We will search all databases from their inception to the present, and we will impose no restrictions on language of publication.
Searching other resources
We will check reference lists of all primary studies and review articles for additional references. We will search relevant manufacturers' websites for trial information.
We will search for errata or retractions from included studies published in full text on PubMed (www.ncbi.nlm.nih.gov/pubmed) and report the date this was done in the review.
Data collection and analysis
Selection of studies
Two review authors (ZM, MV) will independently screen titles and abstracts for inclusion of all the potential studies we identify as a result of the search and code them as 'retrieve' (eligible or potentially eligible/unclear) or 'do not retrieve'. We will retrieve the full‐text study reports/publication, and two review authors (ZM, MV) will independently screen the full text and identify studies for inclusion, and identify and record reasons for exclusion of the ineligible studies. We will resolve any disagreement through discussion or, if required, we will consult a third person (JA). We will identify and exclude duplicates and collate multiple reports of the same study so that each study, rather than each report, is the unit of interest in the review. We will record the selection process in sufficient detail to complete a PRISMA flow diagram and 'Characteristics of excluded studies' table.
Data extraction and management
We will use a data collection form for study characteristics and outcome data that has been piloted on at least one study in the review. One review author (ZM) will extract study characteristics from included studies. We will extract the following study characteristics.
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Methods: study design, total duration of study, details of any 'run in' period, number of study centres and location, study setting, withdrawals, and date of study.
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Participants: N, mean age, age range, gender, severity of condition, diagnostic criteria, baseline lung function, smoking history, inclusion criteria, and exclusion criteria.
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Interventions: intervention, comparison, concomitant medications, and excluded medications.
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Outcomes: primary and secondary outcomes specified and collected, and time points reported.
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Notes: funding for trial and notable conflicts of interest of trial authors.
Two review authors (ZM, VL) will independently extract outcome data from included studies. We will note in the 'Characteristics of included studies' table if outcome data was not reported in a usable way. We will resolve disagreements by consensus or by involving a third person (JA). One review author (ZM) will transfer data into Review Manager. We will double‐check that data is entered correctly by comparing the data presented in the systematic review with the study reports. A second review author (VL) will spot‐check study characteristics for accuracy against the trial report.
Assessment of risk of bias in included studies
Two review authors (ZM, MV) will independently assess risk of bias for each study using the criteria outlined in the Cochrane Handbook for Systematic Reviews of Interventions (Higgins 2011). We will resolve any disagreements by discussion or by involving another review author (JA). We will assess the risk of bias according to the following domains.
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Random sequence generation
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Allocation concealment
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Blinding of participants and personnel
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Blinding of outcome assessment
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Incomplete outcome data
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Selective outcome reporting
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Other bias
We will grade each potential source of bias as high, low, or unclear and provide a quote from the study report together with a justification for our judgement in the 'Risk of bias' table. We will summarise the risk‐of‐bias judgements across different studies for each of the domains listed. We will consider blinding separately for different key outcomes where necessary (for example for unblinded outcome assessment). Where information on risk of bias relates to unpublished data or correspondence with a trialist, we will note this in the 'Risk of bias' table.
When considering treatment effects, we will take into account the risk of bias for the studies that contribute to that outcome.
Assessment of bias in conducting the systematic review
We will conduct the review according to this published protocol and report any deviations from it in the 'Differences between protocol and review' section of the systematic review.
Measures of treatment effect
We will analyse dichotomous data as odds ratios and continuous data as mean difference or standardised mean difference. We will enter data presented as a scale with a consistent direction of effect.
We will undertake meta‐analyses only where this is meaningful, that is if the treatments, participants, and the underlying clinical question are similar enough for pooling to make sense.
We will narratively describe skewed data reported as medians and interquartile ranges.
Where multiple trial arms are reported in a single trial, we will include only the relevant arms. If two comparisons (for example endurance upper limb training versus no training, endurance upper limb training versus strength upper limb training) are combined in the same meta‐analysis, we will halve the control group to avoid double‐counting.
Unit of analysis issues
We will not include crossover trials and do not expect to encounter cluster randomised trials. If we encounter the latter, we will consult the Cochrane Handbook for Systematic Reviews of Interventions (Higgins 2011).
Dealing with missing data
We will contact investigators or study sponsors in order to verify key study characteristics and obtain missing numerical outcome data where possible (for example when a study is identified as abstract only). Where this is not possible, and the missing data are thought to introduce serious bias, we will explore the impact of including such studies in the overall assessment of results by a sensitivity analysis.
Assessment of heterogeneity
We will use the I² statistic to measure heterogeneity among the trials in each analysis. If we identify substantial heterogeneity, we will report it and explore possible causes by prespecified subgroup analysis.
Assessment of reporting biases
If we are able to pool more than 10 trials, we will create and examine a funnel plot to explore possible small study and publication biases.
Data synthesis
We will use a random‐effects model and perform any sensitivity analysis with a random‐effects model.
Summary of findings table
We will create a 'Summary of findings' table using the following outcomes: symptoms of dyspnoea, quality of life, peak upper limb exercise capacity, endurance upper limb exercise capacity, upper limb strength. We will use the five GRADE considerations (study limitations, consistency of effect, imprecision, indirectness, and publication bias) to assess the quality of a body of evidence as it relates to the studies that contribute data to the meta‐analyses for the prespecified outcomes. We will use methods and recommendations described in Section 8.5 and Chapter 12 of the Cochrane Handbook for Systematic Reviews of Interventions (Higgins 2011) using GRADEpro software. We will justify all decisions to down‐ or upgrade the quality of studies using footnotes, and we will make comments to aid readers' understanding of the review where necessary.
Subgroup analysis and investigation of heterogeneity
We plan to carry out the following subgroup analysis.
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Severity of lung disease as severe (FEV1% predicted < 40%) versus not severe (FEV1% predicted ≥ 40%)
We will use the following outcomes in subgroup analysis.
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Symptoms of dyspnoea
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Health‐related quality of life
We will use the formal test for subgroup interactions in Review Manager.
Sensitivity analysis
We will perform sensitivity analysis to analyse the effect of risk of bias. We will perform a separate analysis with only those included studies that have a low risk of bias for at least three of the following domains: random sequence generation, allocation concealment, blinding of outcome assessment, and incomplete outcome data.
