Mechanisms of striated muscle dysfunction during acute exacerbations of COPD

During acute exacerbations of chronic obstructive pulmonary disease (COPD), limb and respiratory muscle dysfunction develops rapidly and functional recovery is partial and slow. The mechanisms leading to this muscle dysfunction are not yet fully established. However, recent evidence has shown that several pathways involved in muscle catabolism, apoptosis, and oxidative stress are activated in the vastus lateralis muscle of patients during acute exacerbations of COPD, while those implicated in mitochondrial function are downregulated. These pathways may be targeted in different ways by factors related to exacerbations. These factors include enhanced systemic inflammation, oxidative stress, impaired energy balance, hypoxia, hypercapnia and acidosis, corticosteroid treatment, and physical inactivity. Data on the respiratory muscles are limited, but these muscles are undoubtedly overloaded during exacerbations. While they are also subjected to the same systemic elements as the limb muscles (except for inactivity), they also face a specific mechanical disadvantage caused by changes in lung volume during exacerbation. The latter will affect the ability to generate force by the foreshortening of the muscle (especially for the diaphragm), but also by altering rib orientation and motion (especially for the parasternal intercostals and the external intercostals). Because acute exacerbations of COPD are associated with an increase in both prevalence and severity of generalized muscle dysfunction, and both remain present even during recovery, early interventions to minimize muscle dysfunction during exacerbation are warranted. Although rehabilitation may be promising, other therapeutic strategies such as counterbalancing the adverse effects of exacerbations on skeletal muscle pathways may also be used.

Daily physical activity in subjects with newly diagnosed COPD

RATIONALE

Information about daily physical activity levels (PAL) in subjects with undiagnosed chronic obstructive pulmonary disease (COPD) is scarce. This study aims to assess PA and to investigate the associations between PA and clinical characteristics in subjects with newly diagnosed COPD.

METHODS

Fifty-nine subjects with a new spirometry-based diagnosis of mild (n=38) and moderate (n=21) COPD (63±6 years, 68% male) were matched with 65 smoking controls (62±7 years, 75% male). PA (daily steps, time spent in moderate-to-vigorous intense physical activities (MVPA) and PAL) was measured by accelerometry. Dyspnoea, complete pulmonary function tests, peripheral muscle strength and exercise capacity served as clinical characteristics.

RESULTS

PA was significantly lower in COPD versus smoking controls (7986±2648 vs 9765±3078 steps, 64 (27-120) vs 110 (55-164) min of MVPA, 1.49±0.21 vs 1.62±0.24 PAL respectively, all p<0.05). Subjects with COPD with either mild symptoms of dyspnoea (mMRC 1), those with lower diffusion capacity (T(L),co), low 6 min walking distance (6MWD) or low maximal oxygen uptake (VO(2) peak) had significantly lower PA. Multiple regression analysis identified 6 MWD and T(L),co as independent predictors of PA in COPD.

CONCLUSIONS

The reduction in PA starts early in the disease, even when subjects are not yet diagnosed with COPD. Inactivity is more pronounced in subjects with mild symptoms of dyspnoea, lower levels of diffusion capacity and exercise capacity.

Impact of exacerbations of cystic fibrosis on muscle strength

Background

Adult patients with cystic fibrosis have peripheral muscle weakness, which is related to exercise intolerance and poor prognosis. The influence of acute exacerbations on muscle strength has been poorly studied. This study aimed to investigate whether quadriceps force (QF), as assessed with an involuntary technique, changes during intravenous antibiotics therapy (IVAT) for an exacerbation.

Methods

QF was measured in 20 patients using twitch stimulation of the femoral nerve at the day of hospitalization (day 1) and at termination (day 14) of the IVAT. Physical activity was monitored during IVAT using a SenseWear armband. Ten stable patients served as control subjects.

Results

QF did not change during exacerbation (potentiated twitch force at day 1: 140 ± 42 N, at day 14: 140 ± 47 N), but a decrease was observed in individual patients. Changes in twitch force during exacerbation were correlated with time spent in activities of at least moderate intensity (r = 0.61, p = 0.007).

Conclusions

QF does not systematically decrease during exacerbations of cystic fibrosis. Individual changes in QF are well correlated with daily time spent in activities of at least moderate intensity.

Perspectives using probe-based confocal laser endomicroscopy of the respiratory tract

QUESTIONS UNDER STUDY/PRINCIPLES

Although probe-based confocal laser endomicroscopy (pCLE) is on the edge of entering daily practice in gastroenterological endoscopy, findings in the field of respiratory medicine are only rarely reported, keeping pCLE during flexible bronchoscopy as a mere preclinical research tool. Since the endomicroscopic aspects of normal bronchial and alveolar tissue have recently been described, we want to take part in the development of a pCLE glossary, describing the pCLE features of pulmonary pathologies.

METHODS

We recruited among patients referred for diagnostic bronchoscopy for pCLE imaging. Images from the central airways were obtained in every patient and alveoloscopy was performed in at least five sub-segments per patient.

RESULTS

Using pCLE imaging, we were able to discriminate normal from abnormal endomicroscopical patterns in four respiratory conditions. These findings were matched with classical histopathology.

CONCLUSION

Reflecting on our own experience using pCLE imaging, we summarise the present state of knowledge, discuss five clinical cases and discuss current limitations and the future promise of this novel imaging tool.

Proprioceptive changes impair balance control in individuals with chronic obstructive pulmonary disease

Introduction

Balance deficits are identified as important risk factors for falling in individuals with chronic obstructive pulmonary disease (COPD). However, the specific use of proprioception, which is of primary importance during balance control, has not been studied in individuals with COPD. The objective was to determine the specific proprioceptive control strategy during postural balance in individuals with COPD and healthy controls, and to assess whether this was related to inspiratory muscle weakness.

Methods

Center of pressure displacement was determined in 20 individuals with COPD and 20 age/gender-matched controls during upright stance on an unstable support surface without vision. Ankle and back muscle vibration were applied to evaluate the relative contribution of different proprioceptive signals used in postural control.

Results

Individuals with COPD showed an increased anterior-posterior body sway during upright stance (p = 0.037). Compared to controls, individuals with COPD showed an increased posterior body sway during ankle muscle vibration (p = 0.047), decreased anterior body sway during back muscle vibration (p = 0.025), and increased posterior body sway during simultaneous ankle-muscle vibration (p = 0.002). Individuals with COPD with the weakest inspiratory muscles showed the greatest reliance on ankle muscle input when compared to the stronger individuals with COPD (p = 0.037).

Conclusions

Individuals with COPD, especially those with inspiratory muscle weakness, increased their reliance on ankle muscle proprioceptive signals and decreased their reliance on back muscle proprioceptive signals during balance control, resulting in a decreased postural stability compared to healthy controls. These proprioceptive changes may be due to an impaired postural contribution of the inspiratory muscles to trunk stability. Further research is required to determine whether interventions such as proprioceptive training and inspiratory muscle training improve postural balance and reduce the fall risk in individuals with COPD.

Measurement validity of an electronic inspiratory loading device during a loaded breathing task in patients with COPD

We studied the validity of a recently introduced, handheld, electronic loading device in providing automatically processed information on external inspiratory work, power and breathing pattern during loaded breathing tasks in patients with COPD. Thirty-five patients with moderate to severe COPD performed an endurance breathing task against a fixed resistive inspiratory load that corresponded to 55 ± 13% of their maximal inspiratory pressure. Flow and pressure signals during this task were sampled and processed at 500 Hz by the handheld loading device and at 100 Hz with an external, laboratory system that provided the "gold standard" reference data. Intra Class Correlations between methods were 0.97 for average mean inspiratory power, 0.98 for average mean pressure, 0.98 for average duty cycle, and 0.99 for total work (all p < 0.0001). We conclude that the handheld device provides automatically processed and valid estimates of physical units of energy during loaded breathing tasks. This enables health care providers to quantify the load on inspiratory muscles during these tests in daily clinical practice.

Chronic obstructive pulmonary disease and comorbidities

Results of epidemiological studies have shown that chronic obstructive pulmonary disease (COPD) is frequently associated with comorbidities, the most serious and prevalent being cardiovascular disease, lung cancer, osteoporosis, muscle weakness, and cachexia. Mechanistically, environmental risk factors such as smoking, unhealthy diet, exacerbations, and physical inactivity or inherent factors such as genetic background and ageing contribute to this association. No convincing evidence has been provided to suggest that treatment of COPD would reduce comorbidities, although some indirect indications are available. Clear evidence that treatment of comorbidities improves COPD is also lacking, although observational studies would suggest such an effect for statins, β blockers, and angiotensin-converting enzyme blockers and receptor antagonists. Large-scale prospective studies are needed. Reduction of common risk factors seems to be the most powerful approach to reduce comorbidities. Whether reduction of so-called spill-over of local inflammation from the lungs or systemic inflammation with inhaled or systemic anti-inflammatory drugs, respectively, would also reduce COPD-related comorbidities is doubtful.

Two distinct chronic obstructive pulmonary disease (COPD) phenotypes are associated with high risk of mortality

RATIONALE

In COPD patients, mortality risk is influenced by age, severity of respiratory disease, and comorbidities. With an unbiased statistical approach we sought to identify clusters of COPD patients and to examine their mortality risk.

METHODS

Stable COPD subjects (n = 527) were classified using hierarchical cluster analysis of clinical, functional and imaging data. The relevance of this classification was validated using prospective follow-up of mortality.

RESULTS

The most relevant patient classification was that based on three clusters (phenotypes). Phenotype 1 included subjects at very low risk of mortality, who had mild respiratory disease and low rates of comorbidities. Phenotype 2 and 3 were at high risk of mortality. Phenotype 2 included younger subjects with severe airflow limitation, emphysema and hyperinflation, low body mass index, and low rates of cardiovascular comorbidities. Phenotype 3 included older subjects with less severe respiratory disease, but higher rates of obesity and cardiovascular comorbidities. Mortality was associated with the severity of airflow limitation in Phenotype 2 but not in Phenotype 3 subjects, and subjects in Phenotype 2 died at younger age.

CONCLUSIONS

We identified three COPD phenotypes, including two phenotypes with high risk of mortality. Subjects within these phenotypes may require different therapeutic interventions to improve their outcome.

Effects of long-acting bronchodilators in COPD patients according to COPD severity and ICS use

BACKGROUND

Indacaterol is a once-daily, long-acting β(2)-agonist bronchodilator that improves dyspnoea and health status in patients with moderate-to-severe COPD. While its bronchodilator effects have been shown to be maintained in different patient subgroups, effects on clinical outcomes in certain subgroups are not yet defined.

METHODS

Post-hoc analysis of pooled clinical study data to investigate efficacy and safety of indacaterol compared with placebo and other long-acting bronchodilators (formoterol, salmeterol, open-label tiotropium) in patient subgroups defined by COPD severity (GOLD stage II or III; n = 4082) and ICS use at baseline (no/yes; n = 4088). Efficacy outcomes were trough (24-h post-dose) FEV(1), dyspnoea (transition dyspnoea index; TDI) and health status (St George's Respiratory Questionnaire; SGRQ) after 26 weeks.

RESULTS

All active treatments significantly improved trough FEV(1) and dyspnoea compared with placebo, and all apart from open-label tiotropium improved health status compared with placebo. Among active treatments, indacaterol 150 μg had the best overall efficacy profile in the GOLD II and no-ICS subgroups. In the GOLD III and ICS subgroups, indacaterol 300 μg had the best overall efficacy, including a marked effect on dyspnoea (1.4-point improvement in TDI total score vs. placebo; p < 0.001). Within subgroups, the incidence of adverse events was similar between treatments.

CONCLUSION

Indacaterol maintained its efficacy regardless of disease severity or use of concurrent ICS. Indacaterol 150 μg had the best overall efficacy profile in the GOLD stage II patients while, in patients with more severe disease, indacaterol 300 μg provided useful improvements in dyspnoea.

The role of bronchodilator treatment in the prevention of exacerbations of COPD

Exacerbations of chronic obstructive pulmonary disease (COPD) are natural events in the progression of the disease, and are characterised by acute worsening of symptoms, especially dyspnoea. These heterogeneous events follow increased airway inflammation, often due to infection, and lead to decreased airflow and increased lung hyperinflation relative to stable COPD. Although exacerbation frequency generally increases as COPD progresses, some patients experience frequent exacerbations (≥ 2 per year) independently of disease severity. Exacerbations, especially frequent exacerbations, are associated with impaired health-related quality of life, reduced physical activity and poor disease prognosis. The cornerstone of pharmacotherapy for stable COPD is long-acting bronchodilators, including the long-acting β(2)-agonists (LABAs) and long-acting anti-muscarinic agents (LAMAs) alone or combined with inhaled corticosteroids (ICS). While ICS treatment can potentially reduce the risk of exacerbations, clinical studies have demonstrated the efficacy of LABAs and LAMAs in reducing COPD symptoms, primarily by reducing lung hyperinflation secondary to reduced airway resistance. Sustained reduction in lung hyperinflation may in turn lessen dyspnoea during an exacerbation. Indeed, recent studies suggest that bronchodilators may also reduce the incidence of, or prevent, exacerbations. Using data from recent studies, this review explores the evidence and possible mechanisms through which bronchodilators may prevent exacerbations.

Eight-step method to build the clinical content of an evidence-based care pathway: the case for COPD exacerbation

BACKGROUND

Optimization of the clinical care process by integration of evidence-based knowledge is one of the active components in care pathways. When studying the impact of a care pathway by using a cluster-randomized design, standardization of the care pathway intervention is crucial. This methodology paper describes the development of the clinical content of an evidence-based care pathway for in-hospital management of chronic obstructive pulmonary disease (COPD) exacerbation in the context of a cluster-randomized controlled trial (cRCT) on care pathway effectiveness.

METHODS

The clinical content of a care pathway for COPD exacerbation was developed based on recognized process design and guideline development methods. Subsequently, based on the COPD case study, a generalized eight-step method was designed to support the development of the clinical content of an evidence-based care pathway.

RESULTS

A set of 38 evidence-based key interventions and a set of 24 process and 15 outcome indicators were developed in eight different steps. Nine Belgian multidisciplinary teams piloted both the set of key interventions and indicators. The key intervention set was judged by the teams as being valid and clinically applicable. In addition, the pilot study showed that the indicators were feasible for the involved clinicians and patients.

CONCLUSIONS

The set of 38 key interventions and the set of process and outcome indicators were found to be appropriate for the development and standardization of the clinical content of the COPD care pathway in the context of a cRCT on pathway effectiveness. The developed eight-step method may facilitate multidisciplinary teams caring for other patient populations in designing the clinical content of their future care pathways.

Peak-end memory bias in laboratory-induced dyspnea: a comparison of patients with medically unexplained symptoms and healthy controls

OBJECTIVE

Memory for unpleasant experiences is dominated by intensity at the experience's peak and end, with a relative neglect for its duration. Therefore, unpleasant somatic experiences are expected be remembered as less aversive when they end gradually rather than abruptly, even when they last longer (i.e., the "peak-end effect"). We investigated the peak-end effect for dyspnea in healthy participants and in patients with medically unexplained dyspnea (MUD).

METHODS

Two aversive dyspnea-inducing tasks were administered to a clinical MUD sample (n = 29) and a matched healthy control group (n = 29) using a rebreathing paradigm (60-second room air, 150-second rebreathing). In a short trial, the breathing system (mouthpiece) was removed immediately after peak dyspnea. In a long trial, breathing was switched to room air after peak dyspnea and continued in the breathing system for 150 seconds (order was counterbalanced across participants). Respiratory parameters were continuously measured, and dyspnea was rated every 10 seconds. Relative unpleasantness of the dyspneic episode was assessed with forced choice questions.

RESULTS

More than 70% of the healthy group found the short episode worse than the long one despite equal maximal dyspnea (p = .02). Patients with MUD did not show this peak-end effect (p = .58). The latter had deficient recovery of dyspnea compared with the controls (42.08 [21.86] versus 17.51 [11.18], p < .001), which could not be explained by differences in respiratory physiology.

CONCLUSIONS

The peak-end effect in dyspnea has important implications for dyspnea measurement. Its absence in patients with MUD suggests a critical role of distorted perceptual-cognitive processing of aversive somatic sensations in patients with medically unexplained symptoms.

Bronchodilation of umeclidinium, a new long-acting muscarinic antagonist, in COPD patients

BACKGROUND

This study evaluated the dose-response of the new long-acting muscarinic antagonist umeclidinium (GSK573719) in patients with COPD.

METHODS

This randomized, double-blind, placebo-controlled, parallel-group study evaluated three once-daily doses of umeclidinium (125, 250 and 500 μg) for 28 days in 285 patients with COPD having FEV(1) of 35-70% predicted (mean (SD) age=61.4 (8.41); mean (SD) post-bronchodilator FEV(1)=1.577 (0.450)). The primary endpoint was morning trough FEV(1) at Day 29. Secondary endpoints included 0-6h weighted mean FEV(1) and serial FEV(1) measured over 6h post-dose and at trough. Safety and pharmacokinetics were also assessed.

RESULTS

All doses of umeclidinium significantly increased trough FEV(1) over placebo from 150 to 168 mL (p<0.001), 0-6h weighted mean FEV(1) from 113 to 211 mL (p<0.001), and serial FEV(1) at each point in time over 24h. Reductions in salbutamol use and improvements in FVC were noted for all doses. Umeclidinium was well tolerated with no apparent treatment-related changes in vital signs.

CONCLUSION

Once-daily umeclidinium provides clinically significant, sustained improvement in lung function and is well tolerated.

Vitamin D supplementation during rehabilitation in COPD: a secondary analysis of a randomized trial

RATIONALE

Pulmonary rehabilitation is an important treatment for patients with Chronic Obstructive Pulmonary Disease, who are often vitamin D deficient. As vitamin D status is linked to skeletal muscle function, we aimed to explore if high dose vitamin D supplementation can improve the outcomes of rehabilitation in Chronic Obstructive Pulmonary Disease.

MATERIAL AND METHODS

This study is a post-hoc subgroup analysis of a larger randomized trial comparing a monthly dose of 100.000 IU of vitamin D with placebo to reduce exacerbations. 50 Subjects who followed a rehabilitation program during the trial are included in this analysis. We report changes from baseline in muscle strength and exercise performance between both study arms after 3 months of rehabilitation.

RESULTS

Vitamin D intervention resulted in significantly higher median vitamin D levels compared to placebo (51 [44-62] ng/ml vs 15 [13-30] ng/ml; p < 0.001). Patients receiving vitamin D had significantly larger improvements in inspiratory muscle strength (-11±12 cmH2O vs 0±14 cmH2O; p = 0.004) and maximal oxygen uptake (110±211 ml/min vs -20±187 ml/min; p = 0.029). Improvements in quadriceps strength (15±16 Nm) or six minutes walking distance (40±55 meter) were not significantly different from the effects in the placebo group (7±19 Nm and 11±74 meter; p>0.050).

CONCLUSION

High dose vitamin D supplementation during rehabilitation may have mild additional benefits to training.

Exacerbation frequency and course of COPD

Background

Exacerbations affect morbidity in chronic obstructive pulmonary disease (COPD). We sought to evaluate the association between exacerbation frequency and spirometric and health status changes over time using data from a large, long-term trial.

Methods

This retrospective analysis of data from the 4-year UPLIFT^® (Understanding Potential Long-term Impacts on Function with Tiotropium) trial compared tiotropium with placebo. Annualized rates of decline and estimated mean differences at each time point were analyzed using a mixed-effects model according to subgroups based on exacerbation frequency (events per patient-year: 0, >0–1, >1–2, and >2). Spirometry and the St George’s Respiratory Questionnaire (SGRQ) were performed at baseline and every 6 months (also at one month for spirometry).

Results

In total, 5992 patients (mean age 65 years, 75% male) were randomized. Higher exacerbation frequency was associated with lower baseline postbronchodilator forced expiratory volume in one second (FEV₁) (1.40, 1.36, 1.26, and 1.14 L) and worsening SGRQ scores (43.7, 44.1, 47.8, and 52.4 units). Corresponding rates of decline in postbronchodilator FEV₁ (mL/year) were 40, 41, 43, and 48 (control), and 34, 38, 48, and 49 (tiotropium). Values for postbronchodilator forced vital capacity decline (mL/year) were 45, 56, 74, and 83 (control), and 43, 57, 83, and 95 (tiotropium). The rates of worsening in total SGRQ score (units/year) were 0.72, 1.16, 1.44, and 1.99 (control), and 0.38, 1.29, 1.68, and 2.86 (tiotropium). The proportion of patients who died (intention-to-treat analysis until four years [1440 days]) for the entire cohort increased with increasing frequency of hospitalized exacerbations.

Conclusion

Increasing frequency of exacerbations worsens the rate of decline in lung function and health-related quality of life in patients with COPD. Increasing rates of hospitalized exacerbations are associated with increasing risk of death.

Longitudinal inspiratory capacity changes in chronic obstructive pulmonary disease

Background

The changes in inspiratory capacity (IC) over time in chronic obstructive pulmonary disease (COPD) patients are unknown. The Understanding Potential Long-term Impacts on Function with Tiotropium (UPLIFT®) trial included IC measurements.

Methods

IC analysis from UPLIFT® (N = 5992) was performed at 1 and 6 months, and every 6 months through 4 years. Annualized rate of decline in pre- and post-bronchodilator IC and mean differences at each time point were analyzed by mixed-effects models. The relationships between baseline IC and exacerbation rate and mortality were explored using Cox regression analysis.

Results

Baseline characteristics: age, 65 years; 75% men; post-bronchodilator forced expiratory volume in 1 second, 1.32 L (48% predicted); pre- and post-bronchodilator IC, 2.03 and 2.33 L. Mean IC rate of decline (mL/year) was 34 ± 2 (1.7% of baseline) and 50 ± 3 (2.1% of baseline) pre- and post-bronchodilator, respectively, without significant between-group differences. Morning pre-bronchodilator (trough) IC improved with tiotropium versus placebo: 124 mL (1 month), 103 mL (1 year), 107 mL (2 years), 98 mL (3 years), and 97 mL (4 years) (all p < 0.001). Post-bronchodilator improvements were similar between treatment groups. Lower baseline IC values were associated with reduced time to first exacerbation. For the lowest quartile (n = 1413) the values in months were 14.3 (11.7–17.0) for tiotropium and 10.3 (8.8–11.7) for controls (p < 0.01).

Conclusion

IC declines from approximately 34 to 50 mL/year in patients with stage II to IV COPD. Tiotropium treatment does not change the IC decline rate but provides 24-hour improvements in IC sustained over the long term. Trough IC differences suggest that tiotropium provides sustained decrease in end-expiratory lung volume.

Randomised controlled trial for emphysema with a selective agonist of the γ-type retinoic acid receptor

Palovarotene is an oral γ-selective retinoid agonist. In animal emphysema models, palovarotene reduced inflammation, promoted structural repair and functional improvement. REPAIR (Retinoid treatment of Emphysema in Patients on the α(1)-antitrypsin International Registry), was an investigator-initiated, double-blind, placebo-controlled randomised study to assess the safety and efficacy of 5 mg·day(-1) palovarotene given for 1 year to 262 patients with severe α(1)-antitrypsin deficiency and emphysema confirmed by computed tomography. Change in volume-adjusted 15th percentile point lung density from baseline in 1 year was the primary end-point; functional end-points were also regularly assessed. We randomly assigned 133 and 129 patients to placebo or palovarotene, respectively. Both groups were well matched for all baseline characteristics, including respiratory medications. 88% and 85% of patients completed 1 year of treatment with placebo and palovarotene, respectively. Palovarotene was generally well tolerated. In the study completers population, the placebo-corrected difference of lung density was -0.45 HU at week 28 (p=0.64) and -0.25 HU at week 52 (p=0.94). A nonsignificant treatment difference in most functional parameters of the lung in favour of the drug was observed over time suggesting potential pharmacological effects of palovarotene. Palovarotene 5 mg·day(-1) over 1 yr failed to show a significant benefit on lung density in moderate-to-severe emphysema secondary to severe α(1)-antitrypsin deficiency.

Quality indicators for in-hospital management of exacerbation of chronic obstructive pulmonary disease: results of an international Delphi study

AIM

To report a Delphi study that was conducted to select process and outcome indicators that are relevant to study quality of care and impact of care pathways for patients hospitalized with exacerbation of chronic obstructive pulmonary disease.

BACKGROUND

Management of patients hospitalized with exacerbation of chronic obstructive pulmonary disease is suboptimal and outcomes are poor. To evaluate the impact of care pathways properly, relevant indicators need to be selected.

DESIGN

Delphi study.

METHODS

The study was conducted over 4 months in 2008, with 35 experts out of 15 countries, including 19 medical doctors, 8 nurses and 8 physiotherapists. Participants were asked to rate, for 72 process and 21 outcome indicators, the relevance for follow-up in care pathways for in-hospital management of exacerbation of chronic obstructive pulmonary disease. Consensus (agreement by at least 75% of the participants) that an indicator is relevant for follow-up was sought in two rounds.

RESULTS

Consensus was reached for 26 of 72 process indicators (36·1%) and 10 of 21 outcome indicators (47·6%). Highest consensus levels were found for the process indicators regarding oxygen therapy (100%), pulmonary rehabilitation (100%) and patient education (94·5-88·6%) and for the outcome indicators concerning understanding of therapy (91·4-85·7%) and self-management (88·6-88·2%).

CONCLUSION

The selected indicators appear to be sensitive for improvement. Therefore, researchers and clinicians that want to study and improve the care for patients hospitalized with exacerbation of chronic obstructive pulmonary disease should primarily focus on these indicators.

Exercise training after lung transplantation improves participation in daily activity: a randomized controlled trial

The effects of exercise training after lung transplantation have not been studied in a randomized controlled trial so far. We investigated whether 3 months of supervised training, initiated immediately after hospital discharge, improve functional recovery and cardiovascular morbidity of patients up to 1 year after lung transplantation. Patients older than 40 years, who experienced an uncomplicated postoperative period, were eligible for this single blind, parallel group study. Sealed envelopes were used to randomly allocate patients to 3 months of exercise training (n = 21) or a control intervention (n = 19). Minutes of daily walking time (primary outcome), physical fitness, quality of life and cardiovascular morbidity were compared between groups adjusting for baseline assessments in a mixed models analysis. After 1 year daily walking time in the treated patients (n = 18) was 85 ± 27 min and in the control group (n = 16) 54 ± 30 min (adjusted difference 26 min [95%CI 8-45 min, p = 0.006]). Quadriceps force (p = 0.001), 6-minute walking distance (p = 0.002) and self-reported physical functioning (p = 0.039) were significantly higher in the intervention group. Average 24 h ambulatory blood pressures were significantly lower in the treated patients (p ≤ 0.01). Based on these results patients should be strongly encouraged to participate in an exercise training intervention after lung transplantation.