Can we identify patients with different illness schema following an acute exacerbation of COPD: a cluster analysis.

INTRODUCTION: Pulmonary Rehabilitation (PR) reduces hospital admissions following an acute exacerbation of Chronic Obstructive Pulmonary Disease (COPD) but adherence is known to be poor. Patients' illness perceptions may affect adherence to disease-management strategies but to date have not been explored following an exacerbation. The study aim is two-fold; firstly to prospectively explore acceptance and uptake of post-exacerbation PR and secondly to identify possible clusters of patients' illness perceptions following hospitalisation for an exacerbation of COPD. METHODS: Patients admitted to hospital with an exacerbation of COPD were recruited to a prospective observational study. Self-reported illness perceptions, mood, health status and self-efficacy were assessed. Acceptance and uptake of PR were recorded at six months. Cluster analysis of Illness Perceptions Questionnaire-Revised data was used to establish groups of patients holding distinct beliefs. RESULTS: 128 patients were recruited. Acceptance and uptake of PR following an acute exacerbation was poor with only 9% (n = 11) completing the programme. Cluster analysis revealed three distinct groups: Cluster 1 'in control' (n = 52), Cluster 2 'disengaged' (n = 36) and Cluster 3 'distressed' (n = 40). Significant between-cluster differences were observed in mood, health status and self-efficacy (p < 0.01). Acceptance and uptake of PR did not differ between clusters. CONCLUSIONS: Acceptance/uptake of post-exacerbation PR was found to be poor. Three distinct illness schema exist in patients following an acute exacerbation. This information may be useful in developing novel psychologically-informed interventions designed to reduce feelings of distress and perhaps facilitate a PR intervention for this vulnerable population.

Have we underestimated the efficacy of pulmonary rehabilitation in improving mood?

BACKGROUND: Patients with COPD have a high prevalence of anxiety and depression. The efficacy of pulmonary rehabilitation (PR) in treating more severe anxiety and depression is unknown. The study aimed to explore the effectiveness of PR in reducing symptoms of anxiety and depression across a spectrum of severities. METHODS: The study used principles of comparative effectiveness research. Data was analysed from 518 patients with COPD [57.5% male, mean (SD) age 69.2 years (± 8.8 years)]. Patients were categorised into 3 groups based on their hospital anxiety and depression scale (HADS) scores pre PR ('none' 0-7, 'probable' 8-10 and 'presence' 11-21). A responder was defined as achieving a change of ≥ 48 m on the incremental shuttle walk test (ISWT). Patients were categorised as 'completers' if they attended their discharge assessment for PR. RESULTS: Anxiety and depression did not reduce following PR in patients with no symptoms (p > 0.05). Patients with a 'probable' or 'presence' of symptoms had significant reductions (both p < 0.001). There was a difference between sub-groups in change for anxiety and depression with patients scoring highest on the HADS having the greatest reductions (p < 0.001). There was no correlation between anxiety or depression and completion of PR (p > 0.05). Responders and non-responders did not differ in their anxiety or depression levels (p > 0.05). CONCLUSION: PR is effective in reducing symptoms of anxiety and depression. Previous studies may have underestimated the effectiveness of the PR programme in improving mood.

Generic, symptom based, exercise rehabilitation; integrating patients with COPD and heart failure.

BACKGROUND: Patients with Chronic Heart Failure (CHF) develop similar symptoms of exertional breathlessness and fatigue as patients with COPD. Although pulmonary (exercise based) rehabilitation (PR) is an integral part of the management of COPD, the potential for exercise rehabilitation (ER) to assist patients with CHF may not be as readily appreciated. We investigated whether combined ER for patients with CHF and COPD was feasible and effective using the model of PR. METHODS: 57 patients with CHF were randomized 2:1 to 7 weeks ER (CHF-ER) or 7 weeks of usual care (CHF-UC). As a comparator 55 patients with COPD were simultaneously recruited to the same ER program (COPD-ER). The primary outcome measure was the Incremental Shuttle Walk Test (ISWT) and the secondary outcome measures were the Endurance Shuttle Walk Test (ESWT), isometric quadriceps strength and health status. RESULTS: 27 CHF and 44 COPD patients completed ER and 17 patients with CHF completed UC. The CHF-ER group made significant improvements, compared to CHF-UC, in the mean (95%CI) ISWT distance; 62(35-89)m vs -6(-11 to 33)m p < 0.001. The CHF-ER group also made statistically significant improvements in health status. The improvements in exercise performance and health status were similar between patients with CHF and COPD, treated with ER. CONCLUSION: Patients with CHF who undergo ER improve similarly in their exercise performance and health status to COPD. Combined training programs for COPD and CHF are effective and feasible, such that service provision could be targeted around common disability rather than the primary organ disease.

Pulmonary rehabilitation is successful for COPD irrespective of MRC dyspnoea grade.

BACKGROUND: It is not clear whether the benefits of pulmonary rehabilitation (PR) apply equally to patients with Chronic Obstructive Pulmonary Disease (COPD) with different levels of starting disability. We have therefore investigated the effect of pulmonary rehabilitation stratified by the MRC dyspnoea scale in patients with COPD. METHODS: This is a retrospective, observational study of data collected from 450 consecutive patients with COPD attending outpatient PR: 247 male, mean (SD) age 69.5 (8.9) yrs and FEV(1) 44.6 (19.7)% predicted. The Incremental Shuttle Walk Test (ISWT) was performed before and after the seven-week course RESULTS: 395 patients (88%) completed the programme. The mean (SD) baseline ISWT performance was 167 (113)m. The distribution of baseline MRC grades was 2 - 15.4%, 3 - 24.9%, 4 - 27.3% and 5 - 32.4%. The mean (95% CI) improvement in ISWT after PR for each MRC scale grade was highly significant (p<0.0005); 2 - 66 (50-83)m, 3 - 63 (50-75)m, 4 - 59 (49-70)m, and 5 - 54 (43-64)m. CONCLUSIONS: Patients with COPD, of all MRC dyspnoea grades, benefit comparably from pulmonary rehabilitation achieving both statistically and clinically meaningful improvements in exercise performance. MRC grade should therefore not be used to exclude patients from pulmonary rehabilitation.

Developing concepts in the pulmonary rehabilitation of COPD.

Randomised trials have demonstrated that pulmonary rehabilitation (PR) can improve dyspnoea, exercise tolerance and health related quality of life. Rehabilitation has traditionally been provided in secondary care to patients with moderate to severe disease. Current concepts are however recommending that it should be delivered in a primary and community care setting for patients with milder disease. There are several opportunities for spreading the word for PR in primary care. One of these is to improve access to PR for all those disabled by their disease by the increase of community schemes and one such scheme being utilised in Canada is reviewed. The essential components of PR include behavior change, patient self-management and prescriptive exercise. In the last decade new strategies have been developed to enhance the effects of exercise training. An overview of these new approaches being an adjunct to exercise training is reviewed. Although the role of exercise training is well established, we are only just beginning to appreciate the importance of behavior change and patient self-management in contributing to improved health and diminished healthcare resource utilisation.

Detecting oxygen desaturation in patients with COPD: incremental versus endurance shuttle walking.

BACKGROUND: There has been no direct comparison between an incremental and endurance walking test to detect the relative oxygen desaturation in patients with chronic obstructive pulmonary disease (COPD). This is of some importance as current guidelines have suggested that ambulatory oxygen should only be prescribed after a standard assessment and desaturation documented. No clear advice about the nature of the required exercise task is given. This study therefore compared the relative desaturation between the incremental shuttle walking test (ISWT) and the constant speed walking test (ESWT) and response to ambulatory oxygen. METHODS: Forty-one patients (29 male), mean (SD), age 71.18 (7.48) yrs, FEV(1) 0.85 (0.29) l with stable COPD were recruited after completion of a 7-week pulmonary rehabilitation programme. Patients completed a baseline (without carrying a cylinder) ISWT and ESWT and then, in random order in double blind fashion, completed the walk tests with a cylinder of air or a cylinder of oxygen. Measurements included distance walked, oxygen saturation, heart rate, perceived breathlessness and exertion (Borg scale). RESULTS: All patients desaturated (<4% below 90%). There was no significant difference in desaturation between the ISWT and the ESWT. There was a significant improvement in performance with supplementary oxygen compared to cylinder air (p<0.05) for both tests. However, compared to the baseline walk, supplementary oxygen did not enhance the distance walked for either test. There was a significant decrease in walking performance on both the ISWT and the ESWT when carrying an air cylinder compared with the control walk. When comparing the percentage difference between oxygen and air for responders (i.e. those that achieve a 10% or more increase), the ESWT showed a greater percentage change 42.1% compared to 26.1% for the ISWT. CONCLUSIONS: This study identifies that incremental and endurance walking provokes significant desaturation and that there is a short-term benefit of oxygen versus air in enhancing exercise performance. There was no significant difference in the level of desaturation between tests. Therefore the ISWT is a suitable exercise test that can be used to evaluate desaturation and is practically more realistic.

Minimum clinically important improvement for the incremental shuttle walking test.

BACKGROUND: The incremental shuttle walking test (ISWT) is used to assess exercise capacity in patients with chronic obstructive pulmonary disease (COPD) and is employed as an outcome measure for pulmonary rehabilitation. This study was designed to establish the minimum clinically important difference for the ISWT. METHODS: 372 patients (205 men) performed an ISWT before and after a 7-week outpatient pulmonary rehabilitation programme. After completing the course, subjects were asked to identify, from a 5-point Likert scale, the perceived change in their exercise performance immediately upon completion of the ISWT. The scale ranged from "better" to "worse". RESULTS: The mean (SD) age was 69.4 (8.4) years, forced expiratory volume in 1 s (FEV(1)) 1.06 (0.53) l and FEV(1)/forced vital capacity (FVC) ratio 50.8 (18.1)%. The baseline shuttle walking test distance was 168.5 (114.6) m which increased to 234.7 (125.3) m after rehabilitation (mean difference 65.9 m (95% CI 58.9 to 72.9)). In subjects who felt their exercise tolerance was "slightly better" the mean improvement was 47.5 m (95% CI 38.6 to 56.5) compared with 78.7 m (95% CI 70.5 to 86.9) in those who reported that their exercise tolerance was "better" and 18.0 m (95% CI 4.5 to 31.5) in those who felt their exercise tolerance was "about the same". CONCLUSION: Two levels of improvement were identified. The minimum clinically important improvement for the ISWT is 47.5 m. In addition, patients were able to distinguish an additional benefit at 78.7 m.

How long should outpatient pulmonary rehabilitation be? A randomised controlled trial of 4 weeks versus 7 weeks.

BACKGROUND: The evidence of benefit for pulmonary rehabilitation (PR) programmes is established. However, the optimal duration of a PR programme is not known. A randomised controlled trial was undertaken in patients with chronic obstructive pulmonary disease (COPD) to assess whether a 4 week PR programme was equivalent to our conventional 7 week PR programme at equivalent time points of 7 weeks and 6 months. METHODS: One hundred patients (56 men) with stable COPD of mean (SD) age 70 (8) years and forced expiratory volume in 1 second (FEV1) 1.13 (0.50) litres were randomised to either a 7 week (n = 50) or 4 week (n = 50) supervised PR programme. Patients were assessed at baseline, at completion of the supervised PR programme, and 6 months later. Patients randomised to the 4 week group were also assessed at the 7 week time point. Outcome measures were the Incremental Shuttle Walk Test, Endurance Shuttle Walk Test (ESWT), Chronic Respiratory Questionnaire-Self Reported, and the Breathing Problems Questionnaire. RESULTS: Forty one patients in each group completed the PR programme. Patients made significant within group improvements after supervised rehabilitation. There were no statistically significant differences between the groups for any other measure at the 7 week or 6 month time points, except that patients in the 4 week group attained higher ESWT times (mean difference 124 seconds (95% CI 17.00 to 232.16), p = 0.024) at the 7 week time point. CONCLUSIONS: A shortened 4 week supervised PR programme is equivalent to a 7 week supervised PR programme at the comparable time points of 7 weeks and 6 months.

Adenine nucleotide loss in the skeletal muscles during exercise in chronic obstructive pulmonary disease.

BACKGROUND: Skeletal muscle adenine nucleotide loss has been associated with fatigue during high intensity exercise in healthy subjects but has not been studied in patients with chronic obstructive pulmonary disease (COPD). Changes in adenine nucleotides and other metabolites in the skeletal muscles were measured in patients with COPD and age matched healthy volunteers by obtaining biopsy samples from the quadriceps muscle at rest and following a standardised exercise challenge. METHODS: Eighteen patients with COPD (mean (SD) forced expiratory volume in 1 second 38.1 (16.8)%) and eight age matched healthy controls were studied. Biopsy samples were taken from the vastus lateralis muscle at rest and immediately after a 5 minute constant workload cycle test performed at 80% peak work achieved during a maximal incremental cycle test performed previously. RESULTS: The absolute workload at which exercise was performed was substantially lower in the COPD group than in the controls (56.7 (15.9) W v 143.2 (26.3) W, p<0.01). Despite this, there was a significant loss of adenosine triphosphate (mean change 4.3 (95% CI -7.0 to -1.6), p<0.01) and accumulation of inosine monophosphate (2.03 (95% CI 0.64 to 3.42), p<0.01) during exercise in the COPD group that was similar to the control group (-4.8 (95% CI -9.7 to 0.08), p = 0.053 and 1.6 (95% CI 0.42 to 2.79), p<0.01, respectively). CONCLUSIONS: These findings indicate that the ATP demands of exercise were not met by resynthesis from oxidative and non-oxidative sources. This suggests that significant metabolic stress occurs in the skeletal muscles of COPD patients during whole body exercise at low absolute workloads similar to those required for activities of daily living.

A profile of daily activity in chronic obstructive pulmonary disease.

BACKGROUND: Little information exists about the pattern of daily activity in patients with chronic obstructive pulmonary disease (COPD), especially in those who are on long-term oxygen therapy (LTOT). The aim of this study was to explore the regular level of domestic physical activity in patients with COPD and to explore differences in activity in those on LTOT. METHODS: Daily activity was recorded using an activity monitor for 7 consecutive days in 4 groups. Group 1 had severe COPD (FEV1 0.66 [0.42] L) receiving LTOT (n = 9). Group 2 had severe COPD (FEV1 1.07 [0.43] L) and had full knowledge of the activity monitor and the purpose of the study (n = 10). Group 3 had severe COPD (FEV1 1.16 [0.27] L) but were unaware of the precise nature of the study (n = 10). Group 4 (n = 10) were the healthy control group. Participants also completed health status questionnaires. RESULTS: There were statistically significant differences in the level of daily activity between all groups (P < .001) except between groups 2 and 3. There were no significant differences between days within groups. The activity counts compared to the healthy groups were reduced by 49% in groups 2 and 3 and by 79% in those on LTOT. CONCLUSION: Patients with COPD demonstrate reduced levels of spontaneous physical activity compared with healthy controls. Furthermore, patients receiving LTOT have an even lower level of domestic activity compared with that of those not on LTOT but with COPD of similar severity.

Postoperative pain detracts from early health status improvement seen after video-assisted thoracoscopic lung volume reduction surgery.

OBJECTIVES: To assess the impact of lung volume reduction surgery (LVRS) on postoperative pain. METHODS: Fifty-two patients, 34 male/18 female, median age 59 (46-70) years, underwent unilateral video-assisted thoracoscopic (VAT) LVRS. FEV(1), TLC, RV and RV/TLC ratio were assessed preoperatively and at 3, 6, 12 and 24 months post surgery. At the same time interval health status was assessed by Euroquol and SF 36 questionnaires. RESULTS: Significant improvements in health status, as assessed by SF 36, persisted from 3 months to 1 year. However, in the pain domain there was a worsening of the mean score from 74 preoperatively to 64 at 3 months, 68 at 6 months, 73 at 12 months and 65 at 24 months. The improvements in Euroquol score were not statistically significant. However, they became significant for at least 2 years postoperatively, when those patients who had a worsening pain score postoperatively were excluded. While the percentage of patients with a worsening of pain scores measured with SF 36 remained between 40 and 45% even 2 years after LVRS, when using Euroquol this percentage did decrease from 30% at 3 months to 14% at 2 years. There was no significant correlation between the change of scores and length of operation, hospital stay or air leak. It was also not statistically significant whether these patients had an extra procedure (redo thoracotomy or insertion of extra drain postoperatively). There were some significant correlations between changes in hyperinflation and changes in pain scores but this was not consistent for Euroquol and SF 36. CONCLUSION: Postoperative pain detracts from global improvement in health status after LVRS even after unilateral VATS. There may be an influence of alterations in chest mechanics after surgery on the development of pain.

Nutritional enhancement of exercise performance in chronic obstructive pulmonary disease: a randomised controlled trial.

BACKGROUND: Pulmonary rehabilitation is effective in improving exercise performance and health status in chronic obstructive pulmonary disease (COPD). However, the role of nutritional support in the enhancement of the benefits of exercise training has not been explored. A double blind, randomised, controlled trial of carbohydrate supplementation was undertaken in patients attending outpatient pulmonary rehabilitation. METHODS: 85 patients with COPD were randomised to receive a 570 kcal carbohydrate rich supplement or a non-nutritive placebo daily for the duration of a 7 week outpatient pulmonary rehabilitation programme. Primary outcome measures were peak and submaximal exercise performance using the shuttle walk tests. Changes in health status, body composition, muscle strength, and dietary macronutrient intake were also measured. RESULTS: Patients in both the supplement and placebo groups increased shuttle walking performance and health status significantly. There was no statistically significant difference between treatment groups in these outcomes. Patients receiving placebo lost weight whereas supplemented patients gained weight. In well nourished patients (BMI >19 kg/m(2)) improvement in incremental shuttle performance was significantly greater in the supplemented group (mean difference between groups: 27 (95% CI 1 to 53) m, p<0.05). Increases in incremental shuttle performance correlated with increases in total carbohydrate intake. CONCLUSIONS: When universally prescribed, carbohydrate supplementation does not enhance the rehabilitation of patients with COPD. This study suggests that exercise training results in negative energy balance that can be overcome by supplementation and that, in selected patients, this may improve the outcome of training. The finding of benefit in well nourished patients may suggest a role for nutritional supplementation beyond the treatment of weight loss in COPD.