An exploration of healthcare-related locus of control in COPD patients attending group-based pulmonary rehabilitation

Abstract

AIMS: Pulmonary rehabilitation is of proven benefit in improving function and health-related quality of life in patients with COPD; however long-term maintenance is poor. Though reasons for this are not fully understood, psychological concepts such as Health Locus of Control (HLOC) may be of interest. This exploratory study aimed to investigate whether HLOC can be altered through pulmonary rehabilitation.

METHODS: A non-randomised uncontrolled before/after design was used. Eligible participants with a diagnosis of COPD and attending their first pulmonary rehabilitation programme were invited to participate. The intervention consisted of standard pulmonary rehabilitation care – a six-week course comprising twice-weekly group-based exercise and education sessions. Participants completed the Multidimensional Health Locus of Control Form-C (MHLC-C) and standard assessments pre (baseline) and post the six-week programme.

RESULTS: Ninety-six patients were invited to participate, 46 consented and 20 completed both pre-and-post study outcomes. Significant improvement between pre-and-post tests were found for two MHLC-C dimensions (Internal: mean increase 5.4, p = 0.012 and Doctors: mean increase 2.1, p = 0.016).

CONCLUSIONS: Though limited by methodological issues, the results tentatively suggest that HLOC can be significantly altered through group-based pulmonary rehabilitation, potentially through enhanced self-management and education strategies empowering patients. Further investigation of these findings and the relationship with long-term maintenance is warranted.

Keywords

COPD locus of control education pulmonary rehabilitation self-management

1 Introduction

Pulmonary rehabilitation has been established as an effective treatment for the management of patients with Chronic Obstructive Pulmonary Disease (COPD), which is a major and pertinent health issue in the North-West of England, with a report by NHS North West’s Respiratory Clinical Pathway Team estimated the percentage of North-West COPD patients as 4.4% of a total population of 3.57 million, translating as approximately 145 000 patients with COPD [1]. Pulmonary rehabilitation is an intervention aimed at improving physical and psychological symptoms in patients with chronic respiratory disease, achieved through exercise, education and behaviour change [2]. It is typically delivered over six-to-eight weeks, with twice-weekly sessions being recommended as per British Thoracic Society (BTS) guidelines [3]. A well-established evidence base exists demonstrating pulmonary rehabilitation’s benefits in terms of exercise capacity and health-related quality of life (HRQoL) [4], anxiety and depression [5], reducing hospital admissions and mortality [6] whilst also demonstrating cost-effectiveness [7]. However, key challenges remain regarding long-term maintenance of these benefits. A range of post-pulmonary rehabilitation programmes have been examined and evidence suggests patients receiving a maintenance intervention post-completion of a programme continue to demonstrate significant improvements in physical functioning compared to patients receiving usual care at six months; though not significant at 12-months [8]. This suggests that patients receiving maintenance support still struggle to retain the benefits of pulmonary rehabilitation beyond six months.

Such concerns have prompted interest in strategies to enhance pulmonary rehabilitation maintenance. In COPD, Wempe and Wijkstra [9] found that patient psychological factors such as mood, cognition and social functioning play a significant role in maintaining rehabilitation benefits. One concept of interest in the long-term management of patients with other conditions (including obesity and diabetes) is Locus of Control (LOC) – defined as “a belief about whether the outcomes of our actions are contingent on what we do (internal control orientation) or on events outside our personal control (external control orientation)” [10]. The generalised standpoint appears to be that Internal LOC approaches (typically referred to within healthcare as Health Locus of Control, or HLOC) are associated with improved long-term condition management strategies. Masters and Wallston [11] found a correlation between a patient’s Internal HLOC orientation and a tendency to view their condition more positively. Internal HLOC orientations have been found to predict improved mastery within cardiac rehabilitation patients [12] supported by findings in research relating to weight loss in obesity [13], diabetic self-management [14] and epilepsy control [15].

Evidence suggests that HLOC is not necessarily a fixed concept, but one that can be altered through group-based interventions. Blair et al. [16] explored HLOC in post-myocardial infarction patients attending cardiac rehabilitation, finding significant changes in Internal (leading to improved individual association between disease-specific behaviour and a patient’s own health) and Chance orientations (where external, non-predictable factors are seen as important) as a result of the intervention. There were also positive associations between increased internality and decreased anxiety, similar to de Boer, Versteegen and Bouman [17] who found significantly increased internal pain management and decreased catastrophizing in patients with chronic pain, supporting similar positive findings into the benefits of multidisciplinary 40-hour chronic pain management in internalising HLOC by Coughlin et al. [18]. Trento et al. [19], in a study of diabetic patients, found that group-based, as opposed to individual care, resulted in the development of higher Internal HLOC levels. Additionally, Rybarczyk et al. [20] examined a variety of physical and psychological outcomes (including HLOC) in 243 patients with various chronic illnesses, finding significant decreases in anxiety, depression and fatigue, as well as changes in the External, Chance and Powerful Others dimensions of the MHLC, maintained for one-year.

Research exploring the concept of HLOC in patients with COPD has received relatively little attention and almost none-at-all in the context of pulmonary rehabilitation and maintenance. The only study identified was conducted in patients with COPD in Taiwan by Chang et al. [21]. 200 COPD patients had their HLOC scores measured following a course of dyspnoea-management strategies and the researchers found a positive correlation between these strategies and an increase in Internal HLOC, as well as decreasing external HLOC dimensions [21]. Though this intervention is not directly comparable to the multi-faceted nature of the pulmonary rehabilitation group, it remains the only major study that has looked at this area and the positively impact of these strategies on Internal HLOC would theoretically suggest comparable links to the management strategies taught within pulmonary rehabilitation groups.

The prevalence of positive associations between Internal HLOC and appropriate condition-specific management in other long-term conditions described earlier however, suggests that developing a more-internalised HLOC could lead to improved self-management in COPD patients, though how this relates to the context of pulmonary rehabilitation is yet unexplored. Therefore, the aim of this study is to explore HLOC in patients with COPD pre-and-post pulmonary rehabilitation.

2 Methodology

2.1 Design

An uncontrolled before/after non-randomised design was used for the study, the same outcome-measures being completed pre-and-post participation in the intervention, which was a pulmonary rehabilitation group [22].

2.2 Participant recruitment

Participants were recruited by purposive sequential sampling from within an integrated COPD service in Central Manchester, UK, that was delivered by nurses and physiotherapists. Participants were referred for pulmonary rehabilitation as part of standard care by either the COPD team, General Practitioners (GPs) or respiratory consultants between February and June of 2014. All patients with a confirmed COPD diagnosis were considered eligible if they met the inclusion criteria. Participation in the study was discussed following their consent to a pulmonary rehabilitation programme in order to limit potential coercion. Some of the patients were new referrals to the COPD service and some were existing COPD service patients who had never previously consented to attend the rehabilitation group.

2.3 Inclusion/Exclusion criteria

Ability to provide informed written consent and confirmed obstructive spirometry as per Global Initiative for Chronic Obstructive Lung Disease guidelines [23] (FEV1/FVC ratio≤70%) or COPD radiographic changes. Exclusion criteria included patients previously completing a pulmonary rehabilitation course, as they may have benefitted from education and self-management strategies that may confound potential HLOC changes.

2.4 Data collection

After giving informed consent, participants completed the standardised rehabilitation assessment which included the Hospital Anxiety and Depression Scale (HADS), the London Chest Activity of Daily Living Scale (LCADL) and the Six-Minute Walk Test (6MWT). In addition, study participants completed the Multidimensional Health Locus of Control Form C (MHLC-C), the primary outcome measure for this study. This was developed by Wallston, Stein and Smith [24] as a condition-specific measure of HLOC when a diagnosis is present. It has been found to have internal consistency and test-retest stability in patients with rheumatoid arthritis [25] and HIV+ [26], with other studies finding that it reflects the overall presentation of a condition rather than simply specific severities [27]; relevant in COPD where FEV1 does not necessarily reflect physical function [28]. The MHLC-C form uses an 18-item six-point Likert scale using statements referring to four separate dimensions of HLOC, Internal, Chance, Doctors and Other People, denoting the dominant dimension governing HLOC in an individual [24]. Rather than being a single overall score, the presentation of each dimension within an individual’s HLOC is reflected by the MHLC-C form, reflecting a multidimensional aspect to HLOC [29].

All questionnaires and 6MWT were completed at baseline assessment and were then repeated at the completion of the six-week programme.

2.5 Description of the pulmonary rehabilitation programme

Between March and June of 2014, all participants commenced the COPD pulmonary rehabilitation programme, following standard care arrangements and assessment as above. Two separate rehabilitation sites were used for the study, with allocation decided by geographic location or patient-preference. The rehabilitation groups were identical in format consisting of twice-weekly provision of a two-hour session comprising of one hour of individualised exercise including cardiovascular and resistance training, and one hour of education and self-management sessions delivered by multidisciplinary team members in line with BTS recommendations [3]. As group exercise and education were delivered by the same team members, information provision was standardised. One group ran as a rolling programme, with new patients assessed and enrolled into an existing group each week, while the other was a static programme with all participants starting and finishing together over an assigned time period. No significant difference has been found between static and rolling programmes [30], with BTS guidelines specifying both can be used [3].

All participants undertook a programme of supervised individualised exercise based on BTS guidelines for a minimum of six-weeks with a qualifying minimum attendance of eight sessions, in line with current BTS guidelines with a minimum of one physiotherapist supervising each session [3].

Ethical approval for the study was granted by the North-Wales Research Ethics Committee’s Proportionate Review Sub-committee (REC reference 14/WA/0046), The University of Manchester’s Research Practice Coordinator (granted 23rd December 2013) and the local NHS Foundation Trust’s Research and Design team (Reference R03516-Edwards). All study participants provided written informed consent.

2.6 Data analysis

Despite the small sample, parametric statistical testing was used for significance as scores for all four-dimensions of the MHLC-C (pre, post and change scores) were normally distributed on inspection, with only pre-rehabilitation values of Doctors and Other People showed any non-normality on Shapiro-Wilk testing (while still relatively normally distributed on inspection of the histogram). Additionally, data showed similar Standard Deviation (SD) levels throughout and were from independent observations. Given the dependant nature of the two-samples to be analysed, a Paired-t test was used for significance testing.

3 Results

Ninety-six patients referred for pulmonary rehabilitation during the study duration were approached regarding participation in the study. Of these, 33 declined to attend, or did not attend initial assessment appointments. A further nine did not meet eligibility criteria and six declined to attend rehabilitation after assessment, another two agreeing to take part in the rehabilitation group but not the study. A further 22 participants initially consented but then withdrew from the pulmonary rehabilitation programme for a variety of reasons (Fig. 1). A further four patients did not achieve the qualifying number of sessions at the study cut-off point. In total, 20 patients completed the minimum qualifying period for study inclusion and completed the MHLC-C form pre-and-post rehabilitation.

Figure 1 shows recruitment and retention for the study period. Of the 96 patients eligible for referral into the study, 63 out of 76 participants that were subsequently withdrawn were excluded due to their own independent decision to not-attend, not participate, or failure to attend further rehabilitation sessions. The demographics of the study sample can be seen in Table 1. As can be seen, there was an even split between participants attending the static and rolling programmes, with more females attending than males. Most participants attending had a GOLD severity of either moderate (stage II) or severe (stage III) disease [23].

3.1 Pre-and-post HLOC score dimension comparison

1 Internal MHLC-C dimension of HLOC

Comparing pre-and-post rehabilitation Internal HLOC levels shows a mean increase of 5.4 on the Internal HLOC dimension with the Paired-t test gives t = 2.78, df = 19 and a Two-Sided P = 0.012, suggesting a significant difference in pre-and-post Internal HLOC level as reported by the MHLC-C (Table 2).

2 Chance MHLC-C dimension of HLOC

Although a decrease in Chance orientation (–1.75) occurs pre-and-post rehabilitation, Paired-t testing shows t = –1.25, df = 19 and Two-Sided P = 0.23, suggesting no significant difference pre-and-post intervention (Table 3).

3 Doctors MHLC-C dimension of HLOC

The data shows a mean increase of 2.05 pre-and-post rehabilitation on the Doctors dimension of the MHLC-C form. The Paired-t test shows t = 2.64, df = 19, Two-Sided P = 0.016 suggesting a significant difference pre-and-post rehabilitation (Table 4).

4 Other People MHLC-C dimension of HLOC

A small mean decrease of –1.25 presents in the Other People dimension of the MHLC-C form during the study. However, such decrease was found to be non-significant with the Paired-t test, with t = –1.27, df = 19 and Two-Sided P = 0.22 (Table 5).

4 Discussion

These exploratory results suggest that internalisation of HLOC occurs in COPD patients undertaking pulmonary rehabilitation and may potential identify areas of interest in developing long-term maintenance strategies, although this requires further exploration due to methodological limitations with the current study.

As can be seen in Table 2, there was a significant increase in Internality score (p = 0.012) following the pulmonary rehabilitation group with a mean increase of 5.4 points from an initial mean baseline Internal score of 23.6. Although the authors of the MHLC-C do not specifically give any Minimally Clinically Important Change (MCIC) values for the tool’s individual categories [24] this increase of 5.4 points represents an increase of 22.9% post-intervention. For comparison, a study by Dodd et al. [31] looking at the results of the COPD Assessment Test (CAT) as an outcome measure following pulmonary rehabilitation found a mean improvement of 2.9 points, or 14.2%. Though clearly not directly relatable, the comparison between this and our 22.9% increase in mean Internal HLOC found in this study does suggests that this increase is likely to be clinically important in the context of pulmonary rehabilitation outcomes.

The increase in internal HLOC, pre-and-post rehabilitation, demonstrated in this study is similar to those findings with self-management strategies in COPD [21], and patients with cardiac conditions following rehabilitation [16]. The findings from the current study add further evidence that HLOC is indeed a flexible, rather than fixed construct. As Internal HLOC orientations are generally associated with improved outcomes in chronic conditions [12 –21], this finding suggests a previously undiscovered positive benefit associated with pulmonary rehabilitation. If HLOC is indeed internalised following a programme of pulmonary rehabilitation, it is postulated that measurable psychological changes can be achieved from pulmonary rehabilitation, in addition to the physical and HRQoL benefits previously described within literature [4]. The prevalent trend was for participant’s HLOC scores generally to regress to the mean, a similar finding to Coughlin et al. within chronic pain [18].

It is considered that one important aspect of this change may be related to improved self-management strategies, achieved through the COPD patient acquiring dyspnoea-management skills, developing pacing strategies and disease-specific knowledge while attending pulmonary rehabilitation. Self-management strategies appear to be effective in improving health status across several different chronic conditions [32] and Blackstock and Webber discuss how didactic education is less effective than specific self-management programmes in improving HRQoL in COPD [33]. Given that the BTS guidelines on pulmonary rehabilitation do not set out specific guidelines regarding format and structure of educational interventions, it may be that some pulmonary rehabilitation programmes fail to deliver education in a way that maximally promotes learning and engagement with the information given, with the potential risk that such information is not retained beyond the sessions. Therefore maintenance of the benefits of rehabilitation are less-effective in these cases than otherwise could be. As the concept of HLOC relates to directly associating one’s own behaviours and the potential future outcome of such behaviours [28], the fact that self-management strategies were utilised within this particular group (including regular technique practice, exercise diaries, question-and-answer sessions) may have empowered patients with knowledge and skills relevant to long-term symptom control. In turn, this may have led to internalisation of HLOC and may provide some insight into how future rehabilitation programmes and education provision can better-address long-term rehabilitation benefit maintenance, something vital to both the patient and the wider NHS, given the significant costs of acute COPD exacerbations on healthcare services [34]. Given that the findings here concur with previous studies in potentially identifying positive associations between group-based self-management interventions and internalised HLOC – maintained long-term – in chronic conditions, further research appears warranted in investigating this particular area with fully powered studies across wider areas of practice using a larger sample size. It is acknowledged however, that given the exploratory nature and small sample size of this study, these findings and discussion should be considered as building-blocks for further investigation, rather than any determinant of future practice.

One interesting aspect of the study is that the other HLOC dimension that significantly increased was Doctors, which is typically associated with an External HLOC orientation [35]. However, within the specific sample used here, participants were actively encouraged as part of the education and self-management talks that should their symptoms worsen and become unmanageable with self-management strategies, they should utilise the integrated COPD acute service that the pulmonary rehabilitation group sits within for support, medication and hospital-at-home services. It is suggested that this may account for the increase in the Doctors dimension of the MHLC-C and in this particular situation, it may actually refer to a positive HLOC outcome when considered alongside the significant increase in Internal HLOC scores. However, detailed investigation of HLOC as a concept is clearly a complex and multifactorial issue beyond the scope of this paper.

4.1 Limitations of study

A significant acknowledged limitation of this study is the sample size of only 20 participants. This has implications for the generalisability of the results to the wider COPD population, given its limited geographical coverage in an area with atypically high COPD population [1]. Additionally, although certain demographics such as age and gender appear similar to reported worldwide COPD averages, only having 5% of participants at Mild (Stage 1) COPD classification is likely well-below that typically reported in the literature [36] and therefore most likely under-representative of the overall population.

Additionally, although attrition rates for pulmonary rehabilitation are typically reported as high in the UK [37] the loss of 61 out of 96 patients referred (63.5%) for varying reasons (Fig. 1) is well above that described in the literature, and limits the study’s generalisability to the UK COPD population. However, it must be stated that this figure includes all referred patients eligible for the study and not just those who consented to attend but subsequently dropped out. When those consenting to start the programme and to consent in the study only are included (n = 46) and those remaining in the group but not reaching the minimum qualifying sessions at the study close date (n = 4) are excluded, the figure of eligible participants completing the programme rises to 47.6%, though it is still acknowledged this is well below accepted national averages [37, 38].

5 Conclusion

Despite the significant limitations imposed by its exploratory nature, this study has identified for the first time that HLOC does appear to be altered by a course of group-based pulmonary rehabilitation, with both Internal and Doctors dimensions of the MHLC-C form being significantly increased as a result of the intervention. These exploratory results may help to provide a platform for further examining the impact of pulmonary rehabilitation on HLOC and specifically how education and self-management strategies are utilised within pulmonary rehabilitation, with potential for developing strategies for teaching both patients and practitioners, with a view to increasing long-term maintenance of its proven and well-documented benefits. However, further studies are required before this can be genuinely considered within a clinical context, with higher-powered trials, RCTs and larger samples needed to confirm and further these initially intriguing findings.

Conflict of interest

Neither author has any conflict of interests with any external agencies and no external funding was sought.

Footnotes

Acknowledgments

This study was carried out for the award of a Masters in Clinical Research at The University of Manchester which was awarded in December 2014.

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