Extra-pulmonary features in COPD patients entering rehabilitation after stratification for MRC dyspnea grade

Investigation of Factors Affecting Shuttle Walking Performance at Increased Speed for Patients with Chronic Obstructive Pulmonary Disease

The aim of this study was to examine the factors affecting the shuttle walking test (SWT) in patients with chronic obstructive pulmonary disease (COPD). A total of 29 patients with COPD (the COPD group) and a healthy group (HG) of 34 women aged between 55 and 74 years were included in the study. After the pulmonary function profiles of the participants were assessed, and the SWT was performed. Walking distances, walking speeds, and SWT levels (SWT-L) were determined with the SWT. Before and after the SWT, the heart rate (HR), oxygen saturation level (SPO2), and Borg scale (perceived exertion (BSe) and dyspnea (BSd)) results were analyzed with a paired sample t-test. The dyspnea levels during activity of daily living were determined with the Medical Research Council (MRC) dyspnea scale, and the relationship between MRC dyspnea (MRCD) and walking distance, speed, and SWT-L was tested using multiple linear regression and Pearson correlation analysis. The walking distance, speed, and SWT-L were lower in the COPD group (p < 0.001) than in the HG. The HR values before and after the SWT changed significantly in the COPD group and the HG (p< 0.001), and the effect size was higher in the COPD group. Although the BSe and BSd results before and after the SWT in the COPD group increased significantly (p < 0.001), they did not change in the HG. There was a highly negative correlation between MRCD and walking distance, speed, and SWT-L in the COPD group (p = 0.002, p = 0.000, and p = 0.001, respectively), but no correlation was found in the HG. The results showed that the HR, perceived exertion, and dyspnea levels of women with COPD whose respiratory functions were lower than the HG were significantly affected on the SWT.

The correlation between quadriceps muscle strength and endurance and exercise performance in patients with COPD

To determine the association between quadriceps muscle strength (QMS) and endurance (QME) and exercise capacity in patients with COPD after stratification for sex and resting lung function (LF). Data were collected from 3,246 patients with COPD (60% men, 64 ± 9 yr), including measures of exercise capacity [peak aerobic capacity (peakV̇o₂), 6-min walk distance (6MWD)] and isokinetic QMS and QME. Patients were stratified for sex, forced expiratory volume in 1 s (>50/≤50% predicted), single breath carbon monoxide diffusing capacity (>50/≤50% predicted), and residual volume (>140/≤140% predicted). After stratification for resting LF, QMS and QME were significantly associated with peakV̇o₂ (r range: 0.47-0.61 and 0.49-0.65 for men and 0.53-0.66 and 0.48-0.67 for women, respectively) and 6MWD (r range: 0.29-0.42 and 0.44-0.55 for men and 0.25-0.54 and 0.34-0.55 for women, respectively) (P < 0.001). Regression models demonstrated that QMS and QME were significant determinants of peakV̇o₂ (explained variance R² range: 35.6%-48.8% for men and 36.8%-49.0% for women) and 6MWD (R² range: 24.3%-43.3% for men and 28.4%-40.3% for women), independent of age and fat-free mass. Quadriceps muscle function was significantly associated with peakV̇o₂ and 6MWD in male and female patients with COPD after stratification for resting LF, in which QME appear to be a more important determinant than QMS. This underlines the importance of systematically evaluating both quadriceps muscle strength and endurance in in all patients with COPD.NEW & NOTEWORTHY Our findings identified quadriceps muscle function as an important determinant of exercise capacity across a wide spectrum of lung function. Quadriceps muscle endurance appears to be a more important determinant than quadriceps muscle strength, underlining the importance of including both the measurement of quadriceps muscle strength and endurance in routine assessment for all patient with COPD.

Profiling of Patients with COPD for Adequate Referral to Exercise-Based Care: The Dutch Model

A loss of physical functioning (i.e., a low physical capacity and/or a low physical activity) is a common feature in patients with chronic obstructive pulmonary disease (COPD). To date, the primary care physiotherapy and specialized pulmonary rehabilitation are clearly underused, and limited to patients with a moderate to very severe degree of airflow limitation (GOLD stage 2 or higher). However, improved referral rates are a necessity to lower the burden for patients with COPD and for society. Therefore, a multidisciplinary group of healthcare professionals and scientists proposes a new model for referral of patients with COPD to the right type of exercise-based care, irrespective of the degree of airflow limitation. Indeed, disease instability (recent hospitalization, yes/no), the burden of disease (no/low, mild/moderate or high), physical capacity (low or preserved) and physical activity (low or preserved) need to be used to allocate patients to one of the six distinct patient profiles. Patients with profile 1 or 2 will not be referred for physiotherapy; patients with profiles 3-5 will be referred for primary care physiotherapy; and patients with profile 6 will be referred for screening for specialized pulmonary rehabilitation. The proposed Dutch model has the intention to get the right patient with COPD allocated to the right type of exercise-based care and at the right moment.

Effect of Sustained-Release Morphine for Refractory Breathlessness in Chronic Obstructive Pulmonary Disease on Health Status: A Randomized Clinical Trial

IMPORTANCE

Morphine is used as palliative treatment of chronic breathlessness in patients with advanced chronic obstructive pulmonary disease (COPD). Evidence on respiratory adverse effects and health status is scarce and conflicting.

OBJECTIVE

To assess the effects of regular, low-dose, oral sustained-release morphine on disease-specific health status (COPD Assessment Test; CAT), respiratory outcomes, and breathlessness in patients with COPD.

INTERVENTIONS

Participants were randomly assigned to 10 mg of regular, oral sustained-release morphine or placebo twice daily for 4 weeks, with the possibility to increase to 3 times daily after 1 or 2 weeks.

DESIGN, SETTING, AND PARTICIPANTS

The Morphine for Treatment of Dyspnea in Patients With COPD (MORDYC) study was a randomized, double-blind, and placebo-controlled study of a 4-week intervention. Patients were enrolled between November 1, 2016, and January 24, 2019. Participants were recruited in a pulmonary rehabilitation center and 2 general hospitals after completion of a pulmonary rehabilitation program. Outpatients with COPD and moderate to very severe chronic breathlessness (modified Medical Research Council [mMRC] breathlessness grades 2-4) despite optimal pharmacological and nonpharmacological treatment were included. A total of 1380 patients were screened, 916 were ineligible, and 340 declined to participate.

MAIN OUTCOMES AND MEASURES

Primary outcomes were CAT score (higher scores represent worse health status) and arterial partial pressure of carbon dioxide (Paco2). Secondary outcome was breathlessness in the previous 24 hours (numeric rating scale). Data were analyzed by intention to treat. Subgroup analyses in participants with mMRC grades 3 to 4 were performed.

RESULTS

A total of 111 of 124 included participants were analyzed (mean [SD] age, 65.4 [8.0] years; 60 men [54%]). Difference in CAT score was 2.18 points lower in the morphine group (95% CI, -4.14 to -0.22 points; P = .03). Difference in Paco2 was 1.19 mm Hg higher in the morphine group (95% CI, -2.70 to 5.07 mm Hg; P = .55). Breathlessness remained unchanged. Worst breathlessness improved in participants with mMRC grades 3 to 4 (1.33 points lower in the morphine group; 95% CI, -2.50 to -0.16 points; P = .03). Five participants of 54 in the morphine group (9%) and 1 participant of 57 in the placebo group (2%) withdrew because of adverse effects. No morphine-related hospital admissions or deaths occurred.

CONCLUSIONS AND RELEVANCE

In this randomized clinical trial, regular, low-dose, oral sustained-release morphine for 4 weeks improved disease-specific health status in patients with COPD without affecting Paco2 or causing serious adverse effects. The worst breathlessness improved in participants with mMRC grades 3 to 4. A larger randomized clinical trial with longer follow-up in patients with mMRC grades 3 to 4 is warranted.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02429050.

Association between patient-reported outcomes and exercise test outcomes in patients with COPD before and after pulmonary rehabilitation

Background

Over the years, the scope of outcomes assessment in chronic obstructive pulmonary disease (COPD) has broadened, allowing for the evaluation of various patient-reported outcomes (PROs). As it still remains unclear whether and to what extent PROs mirror the exercise performance of patients with COPD, the current study aimed to assess the association between different exercise test outcomes and PROs, before and after pulmonary rehabilitation (PR).

Methods

Correlations between PROs used to describe health-related quality of life (HRQoL), mood status, level of care dependency and dyspnea in patients with COPD and commonly used laboratory- and field-based exercise test outcomes were evaluated in 518 individuals with COPD attending PR.

Results

Overall, correlations between PROs and exercise test outcomes at baseline were statistically significant. The correlation between modified Medical Research Council (mMRC) dyspnea score and 6-min walking distance (6MWD) was strongest (ρ:-0.65; p<0.001). HRQoL related PROs showed weak correlations with exercise outcomes at baseline. Moderate correlations were found between St George’s Respiratory Questionnaire total score and 6MWD (r:-0.53; p<0.001) and maximal workload achieved during cardiopulmonary exercise testing (ρ:-0.48; p<0.001); and between Clinical COPD Questionnaire (CCQ) total score and 6MWD (r:-0.48; p<0.001) and maximal workload (ρ:-0.43; p<0.001). When significant, correlations between changes in exercise test outcomes and changes in PROs after PR were generally very weak or weak. The highest correlation was found between changes in CCQ total score and changes in 6MWD (ρ: − 0.36; p<0.001).

Conclusions

PROs and exercise test outcomes, although significantly correlated with each other, assess different disease features in patients with COPD. Individual PROs need to be supported by additional functional measurements whenever possible, in order to get a more detailed insight in the effectiveness of a PR program.

Trial registration

Netherlands Trial Register (NL3263/NTR3416). Registered 2 May 2012.

Skin auto-fluorescence as a measure of advanced glycation end-products is associated with microvascular health in patients with COPD

BACKGROUND AND OBJECTIVES

Chronic obstructive pulmonary disease (COPD) is associated with systemic inflammation and oxidative stress. These physiological processes can lead to increased formation and accumulation of advanced glycation end-products (AGEs), that can play a role in vascular complications. In this cross-sectional study, we determined the association between skin AGEs and microvascular health in patients with COPD.

METHODS

Clinical characteristics and cardiovascular parameters, including pulmonary function, metabolic and inflammatory parameters, and blood pressure, were obtained in this observational study with patients with COPD. Skin concentrations of AGEs were assessed non-invasively by measuring skin autofluorescence (AF). Retinal vessel analysis was used as a marker of microvascular health.

RESULTS

62 patients with COPD (52% males; mean age: 64.4 ± 8.4 years; mean FEV₁: 45.0 ± 20.7%pred.) were analysed. Mean skin AF was 2.75 ± 0.64 arbitrary units. Skin AF in patients with COPD was negatively associated with retinal arteriolar diameter (β -0.021, 95% CI -0.040 to -0.002; p = 0.031) and arteriole-to-venular ratio (β -7.233, 95% CI -9.732 to -4.734; p < 0.001) and positively associated with retinal venular diameter (β 0.029, 95% CI 0.019 to 0.038; p < 0.001) after adjustment for sex, age, lung function, pack-years of smoking and conventional cardiovascular risk factors.

CONCLUSION

We document for the first time that skin AF in patients with COPD is independently associated with retinal arteriolar and venular vessel diameters, biological indicators for microvascular health. This adds to the evidence that AGEs are an accessible marker of microvascular health.

GPNMB contributes to a vicious circle for chronic obstructive pulmonary disease

Osteoporosis (OP) is significant and debilitating comorbidity of chronic obstructive pulmonary disease (COPD). We hypothesize that genetic variance identified with OP may also play roles in COPD. We have conducted a large-scale relation data analysis to explore the genes implicated with either OP or COPD, or both. Each gene linked to OP but not to COPD was further explored in a mega-analysis and partial mega-analysis of 15 independently collected COPD RNA expression datasets, followed by gene set enrichment analysis (GSEA) and literature-based pathway analysis to explore their functional linked to COPD. A multiple linear regression (MLR) model was built to study the possible influence of sample size, population region, and study date on the gene expression data in COPD. At the first step of the analysis, we have identified 918 genes associated with COPD, 581 with OP, and a significant overlap (P<2.30e-140; 210 overlapped genes). Partial mega-analysis showed that, one OP gene, GPNMB presented significantly increased expression in COPD patients (P-value = 0.0018; log fold change = 0.83). GPNMB was enriched in multiple COPD pathways and plays roles as a gene hub formulating multiple vicious COPD pathways included gene MMP9 and MYC. GPNMB could be a novel gene that plays roles in both COPD and OP. Partial mega-analysis is valuable in identify case-specific genes for COPD.

Structural analysis of retinal blood vessels in patients with COPD during a pulmonary rehabilitation program

Cardiovascular diseases are frequently present in chronic obstructive pulmonary disease (COPD). Population-based studies found associations between retinal vessel diameters and cardiovascular health, but it is unknown whether this also applies to COPD patients. Therefore, we measured retinal vessel diameters in COPD patients and aimed to determine the association with cardiovascular risk factors, lung function, and functional outcomes. In addition, we investigated whether an exercise-based pulmonary rehabilitation (PR) program would change retinal vessel diameters, as a proxy for improved microvascular health. Demographics and clinical characteristics, including pulmonary function, exercise capacity, blood pressure, blood measurements and level of systemic inflammation were obtained from 246 patients during routine assessment before and after PR. Retinal vessel diameters were measured from digital retinal images. Older age and higher systolic blood pressure were associated with narrower retinal arterioles (β: -0.224; p = 0.042 and β: -0.136; p < 0.001, respectively). Older age, higher systolic blood pressure and lower level of systemic inflammation were associated with narrower retinal venules (β: -0.654; -0.229; and -13.767, respectively; p < 0.05). No associations were found between retinal vessel diameters and lung function parameters or functional outcomes. After PR, no significant changes in retinal venular or arteriolar diameter were found. To conclude, retinal vessel diameters of COPD patients were significantly associated with systolic blood pressure and systemic inflammation, whilst there was no evidence for an association with lung function parameters, functional outcomes or other cardiovascular risk factors. Furthermore, an exercise-based PR program did not affect retinal vessel diameter.

Wearable Cardiopulmonary Function Evaluation System for Six-Minute Walking Test

As a submaximal exercise test, a 6-min walking test (6MWT) can be considered a suitable index for the exercise capacity of patients with a respiratory problem. Traditionally, medical staff manually collect cardiopulmonary information using different devices. However, no integrated monitoring system is currently available to simultaneously record the real-time breathing sound, heart rhythm, and precise walking information (i.e., walking distance, speed, and acceleration) during the 6MWT. In this study, a wearable and wireless multiparameter monitoring system is proposed to simultaneously monitor the breathing sound, oxygen saturation (SpO2), electrocardiograph (ECG) signals, and precise walking information during the 6MWT. Here, a wearable mechanical design was successfully used to reduce the effect of motion artifacts on the breathing sound and ECG signal. A multiparameter detection algorithm was designed to effectively estimate heart and breathing rates. Finally, the cardiopulmonary function of smokers was evaluated using the proposed system. The evaluation indicated that this system could reveal dynamic changes and differences in the breathing rate, heart rate, SpO2, walking speed, and acceleration during the 6MWT. The proposed system can serve as a more integrated approach to monitor cardiopulmonary parameters and obtain precise walking information simultaneously during the 6MWT.

Skeletal Muscle Dysfunction in Chronic Obstructive Pulmonary Disease. What We Know and Can Do for Our Patients

Skeletal muscle dysfunction occurs in patients with chronic obstructive pulmonary disease (COPD) and affects both ventilatory and nonventilatory muscle groups. It represents a very important comorbidity that is associated with poor quality of life and reduced survival. It results from a complex combination of functional, metabolic, and anatomical alterations leading to suboptimal muscle work. Muscle atrophy, altered fiber type and metabolism, and chest wall remodeling, in the case of the respiratory muscles, are relevant etiological contributors to this process. Muscle dysfunction worsens during COPD exacerbations, rendering patients progressively less able to perform activities of daily living, and it is also associated with poor outcomes. Muscle recovery measures consisting of a combination of pulmonary rehabilitation, optimized nutrition, and other strategies are associated with better prognosis when administered in stable patients as well as after exacerbations. A deeper understanding of this process' pathophysiology and clinical relevance will facilitate the use of measures to alleviate its effects and potentially improve patients' outcomes. In this review, a general overview of skeletal muscle dysfunction in COPD is offered to highlight its relevance and magnitude to expert practitioners and scientists as well as to the average clinician dealing with patients with chronic respiratory diseases.

Molecular Characteristics and Treatment of Endothelial Dysfunction in Patients with COPD: A Review Article

Patients with chronic obstructive pulmonary disease (COPD) show systemic consequences, such as chronic systemic inflammation leading to changes in the airway, airway penetrability, and endothelial function. Endothelial dysfunction is characterized by a list of alterations of endothelium towards reduced vasodilation, proinflammatory state, detachment and apoptosis of endothelial cells, and development of atherosclerosis. COPD-induced endothelial dysfunction is associated with elevated cardiovascular risk. The increment of physical activities such as pulmonary rehabilitation (PR) training have a significant effect on COPD, thus, PR can be an integrative part of COPD treatment. In this narrative review the focus is on the function of endothelial inflammatory mediators [cytokines, chemokines, and cellular proteases] and pulmonary endothelial cells and endothelial dysfunction in COPD as well as the effects of dysfunction of the endothelium may play in COPD-related pulmonary hypertension. The relationship between smoking and endothelial dysfunction is also discussed. The connection between different pulmonary rehabilitation programs, arterial stiffness and pulse wave velocity (PWV) is presented. Endothelial dysfunction is a significant prognostic factor of COPD, which can be characterized by PWV. We discuss future considerations, like training programs, as an important part of the treatment that has a favorable impact on the endothelial function.

Effectiveness of a 4-week rehabilitation program on endothelial function, blood vessel elasticity in patients with chronic obstructive pulmonary disease

Background

Chronic obstructive pulmonary disease (COPD) may have considerable cardiovascular risk. Physical activity has a paramount role in COPD treatment. Our aim was to evaluate the applicability of arteriograph in COPD and measure the effectiveness of pulmonary rehabilitation on endothelial function.

Methods

A total of 40 patients with COPD (FEV₁: 45.43±20.20%pred, BMI: 27.99±6.98 kg/m², male: female was 21:19, age: 65.47±7.39 years) participated in a 4-week rehabilitation program. We used a patented, invasively validated Arteriograph. Blood pressure, pulse, augmentation index (AIX), pulse wave velocity (PWV), diastolic area index (DAI) were registered with functional measurements in pulmonary rehabilitation.

Results

Pulmonary rehabilitation was effective in 6 minutes walking distance (6MWD: 335.32±110.43 vs. 398.32±126.21 m), maximal inspiratory pressure (MIP: 57.72±22.69 vs. 63.63±18.01 cmH₂O), chest wall expansion (CWE: 2.84±1.26 vs. 4.00±1.76 cm), breath holding time (BHT: 25.77±10.63 to 29.21±11.60 sec) and grip strength (GS: 24.87±11.88 vs. 27.03±11.43 kg) (P<0.05). Improvement in quality of life was monitored by COPD assessment test marker (CAT: 17.00±8.49 vs. 11.89±7.31, P<0.05). Systolic (133.38±22.15 vs. 126.48±20.22 mmHg) and diastolic blood pressure (76.95±14.37 vs. 75.4±12.7 mmHg) showed a reduction tendency. Pulse also decreased (76.95±14.37 vs. 72.53±13.65 bpm). AIX levels showed slight improvement (3.54±35.59% vs. 2.93±30.79%); 23 patients peripheral circulation progressed. The PWV data showed abnormal elasticity with minimal change (11.74±2.13 vs. 11.4±2.73 m/s); although 20 patients showed improvement. DAI detected slightly diminished coronary circulation with moderate improvement (43.32±6.81 vs. 47.1±7.01 m/s).

Conclusions

Elevated arterial stiffness, high PWV turned the COPD patients to the high/very high-risk cluster. Rehabilitation resulted significant improvement in MIP, CWE, BHT, 6MWD, CAT with mild, but favorable changes in blood pressure, pulse, AIX, PWV. As a consequence of the four weeks rehabilitation period overall quality of life improved and cardiovascular risk showed a reduction tendency in COPD.

Muscle strengthening activity associates with reduced all-cause mortality in COPD

Objective Emerging research suggests that aerobic-based physical activity may help to promote survival among chronic obstructive pulmonary disease patients. However, the extent to which engagement in resistance training on survival among chronic obstructive pulmonary disease patients is relatively unknown. Therefore, the purpose of this study was to examine the independent associations of muscle strengthening activities on all-cause mortality among a national sample of U.S. adults with chronic obstructive pulmonary disease. We hypothesize that muscle strengthening activities will be inversely associated with all-cause mortality. Methods Data from the 2003-2006 NHANES were employed, with follow-up through 2011. Aerobic-based physical activity was objectively measured via accelerometry, muscle strengthening activities engagement was assessed via self-report, and chronic obstructive pulmonary disease was assessed via physician-diagnosis. Results Analysis included 385 adults (20 + yrs) with chronic obstructive pulmonary disease, who represent 13.3 million chronic obstructive pulmonary disease patients in the USA. The median follow-up period was 78 months (IQR=64-90), with 82 chronic obstructive pulmonary disease patients dying during this period. For a two muscle strengthening activity sessions/week increase (consistent with national guidelines), chronic obstructive pulmonary disease patients had a 29% reduced risk of all-cause mortality (HR=0.71; 95% CI: 0.51-0.99; P = 0.04). Conclusion Participation in muscle strengthening activities, independent of aerobic-based physical activity and other potential confounders, is associated with greater survival among chronic obstructive pulmonary disease patients.

The Effect of Fatigue and Fatigue Intensity on Exercise Tolerance in Moderate COPD

INTRODUCTION

Fatigue is one of the most disabling symptoms in COPD, but little is known about the impact of fatigue on functional disability. We explored the impact of fatigue and fatigue intensity on exercise tolerance after adjusting for other factors using multivariate analysis and compared it to that of dyspnoea.

METHODS

A total of 119 patients with mainly moderate-severe stable COPD (38 % women, mean age 66 years) were enrolled. We used the Medical Research Council dyspnoea scores (MRC), Manchester COPD fatigue scale (MCFS) and its three dimensions, Borg scales for fatigue and dyspnoea, six-minute walk distance (6MWD), St George's Respiratory Questionnaire, the BODE index, and the Centre for Epidemiological Study on Depression scale (CES-D), and we measured spirometry, blood gases, systemic inflammatory markers and fat-free mass index (FFMI).

RESULTS

Fatigue measured using the MCFS was associated with 6MWD and explained 22 % of the variability in 6MWD (p < 0.001). Fatigue remained associated with 6MWD after adjusting for MRC dyspnoea, FFMI and FEV1, FVC, PaO2, PaCO2, CES-D, TNF-alpha, smoking status, age and gender. We found that 33, 50 and 23 % of patients reported an increase by 2 scores on Borg scales for fatigue, dyspnoea or both at the end of the 6MWT. Fatigue scores (both before and after the 6MWT) were negatively correlated with 6MWD after adjusting for FEV1, FFMI, CES-D score and age (p = 0.007 and 0.001, respectively).

CONCLUSION

In moderate stable COPD, fatigue may be a central driver of functional disability, to the same extent as dyspnoea.

Differences in change in coping styles between good responders, moderate responders and non-responders to pulmonary rehabilitation

INTRODUCTION

Pulmonary rehabilitation (PR) improves exercise tolerance and health status in patients with chronic obstructive pulmonary disease (COPD). Data on the effects of PR on coping styles are limited. Aim of the present study was to compare changes in coping styles between patients who had a good, moderate and no improvement in either exercise tolerance or health status after PR.

METHODS

Coping styles of 439 COPD patients undergoing PR were assessed by the Utrecht Coping List (UCL) at baseline and after PR. Patients' pulmonary function, six-minute walking distance (6MWD), St. George's Respiratory Questionnaire (SGRQ) and Hospital Anxiety and Depression Scale (HADS-A and HADS-D) were recorded. Good, moderate and non-responders were defined on the basis of minimally clinically important difference (MCID) for SGRQ total score and/or 6MWD.

RESULTS

Overall, 54.0% of the patients fulfilled the criteria for good responders, while 22.1% were moderate responders. Change in passive reaction pattern coping style differed significantly between good responders and non-responders following PR (p < 0.001). Moreover, within the groups, changes in coping styles after PR occurred among the good responders, whereas the majority of moderate responders' and non-responders' coping styles were not significantly influenced by PR.

CONCLUSION

Good responders decreased their passive reaction pattern coping style in contrast to non-responders after PR. In general, PR did not change the coping among moderate and non-responders. Further research is warranted to determine whether including interventions targeting coping styles may modify coping behaviour of COPD patients, as well as improvement in exercise tolerance or health status after PR.

Differential response to pulmonary rehabilitation in COPD: multidimensional profiling

The aim of the present study was to profile a multidimensional response to pulmonary rehabilitation in patients with chronic obstructive pulmonary disease (COPD).Dyspnoea, exercise performance, health status, mood status and problematic activities of daily life were assessed before and after a 40-session pulmonary rehabilitation programme in 2068 patients with COPD (mean forced expiratory volume in 1 s of 49% predicted). Patients were ordered by their overall similarity concerning their multidimensional response profile, which comprises the overall response on MRC dyspnoea grade, 6MWD, cycle endurance time, Canadian Occupational Performance Measure performance and satisfaction scores, Hospital Anxiety and Depression Scale anxiety and depression, and St George's Respiratory Questionnaire total score, using a novel non-parametric regression technique.Patients were clustered into four groups with distinct multidimensional response profiles: n=378 (18.3%; "very good responder"), n=742 (35.9%; "good responder"), n=731 (35.4%; "moderate responder"), and n=217 (10.5%; "poor responder"). Patients in the "very good responder" cluster had higher symptoms of dyspnoea, number of hospitalisations <12 months, worse exercise performance, worse performance and satisfaction scores for problematic activities of daily life, more symptoms of anxiety and depression, worse health status, and a higher proportion of patients following an inpatient PR programme compared to the other three clusters.A multidimensional response outcome needs to be considered to study the efficacy of pulmonary rehabilitation services in patients with COPD, as responses to regular outcomes are differential within patients with COPD.

One-year change in health status and subsequent outcomes in COPD

BACKGROUND

Poor health status has been associated with morbidity and mortality in patients with COPD. To date, the impact of changes in health status on these outcomes remains unknown.

AIMS

To explore the relationship of clinically relevant changes in health status with exacerbation, hospitalisation or death in patients with COPD.

METHODS

Characteristics and health status (St George's Respiratory Questionnaire, SGRQ) were assessed over a period of 3 years in 2138 patients with COPD enrolled in the Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints (ECLIPSE) study: a longitudinal, prospective, observational study. Associations between change in health status (=4 units in SGRQ score) during year 1 and time to first exacerbation, hospitalisation and death during 2-year follow-up were assessed using Kaplan-Meier plots and log-rank test.

RESULTS

1832 (85.7%) patients (age 63.4±7.0 years, 65.4% male, FEV1 48.7±15.6% predicted) underwent assessment at baseline and 1 year. Compared with those who deteriorated, patients with improved or stable health status in year 1 have a lower likelihood of exacerbation (HR 0.78 (95% CI 0.67 to 0.89), p<0.001 and 0.84 (0.73 to 0.97), p=0.016, respectively), hospitalisation (0.72 (0.58 to 0.90), p=0.004 and 0.77 (0.62 to 0.96), p=0.023, respectively) or dying (0.61 (0.39 to 0.95), p=0.027 and 0.58 (0.37 to 0.92), p=0.019, respectively) during 2-year follow-up. This effect persisted after stratification for age and the number of exacerbations and hospitalisations during the first year of the study.

CONCLUSIONS

Patients with stable or improved health status during year 1 of ECLIPSE had a lower likelihood of exacerbation, hospitalisation or dying during 2-year follow-up. Interventions that stabilise and improve health status may also improve outcomes in patients with COPD.

TRIAL REGISTRATION NUMBER

NCT00292552, registered at ClinicalTrials.gov.

Noninvasive tests for the diagnostic evaluation of dyspnea among outpatients: the Multi-Ethnic Study of Atherosclerosis lung study

BACKGROUND

Dyspnea on exertion is a common and debilitating symptom, yet evidence for the relative value of cardiac and pulmonary tests for the evaluation of chronic dyspnea among adults without known cardiac or pulmonary disease is limited.

METHODS

The Multi-Ethnic Study of Atherosclerosis (MESA) enrolled participants aged 45 to 84 years who were free of clinical cardiovascular disease from 6 communities; participants with clinical pulmonary disease were excluded from this report. Dyspnea on exertion was assessed via structured interview. Tests included electrocardiograms, cardiac computed tomography (CT) for coronary artery calcium, cardiac magnetic resonance imaging, spirometry, percent emphysema (percent of lung regions <-950 HU) on CT, inflammatory biomarkers, and N-terminal pro-brain natriuretic peptide (NT-proBNP). Logistic regression was used to identify independent correlates of dyspnea after adjustment for age, sex, body mass index, physical activity, anxiety, and leg pain.

RESULTS

Among 1969 participants without known cardiopulmonary disease, 9% had dyspnea. The forced expiratory volume in 1 second (FEV1) (P < .001), NT-proBNP (P = .004), and percent emphysema on CT (P = .004) provided independent information on the probability of self-reported dyspnea. Associations with the FEV1 were stronger among smokers and participants with other recent respiratory symptoms or seasonal allergies; associations with NT-proBNP were present only among participants with coexisting symptoms of lower-extremity edema. Only the FEV1 provided a significant improvement in the receiver operating curve.

CONCLUSIONS

Among adults without known cardiac or pulmonary disease reporting dyspnea on exertion, spirometry, NT-proBNP, and CT imaging for pulmonary parenchymal disease were the most informative tests.

The 2014 Updated GOLD Strategy: A Comparison of the Various Scenarios

Background: The 2014 updated Global initiative for chronic Obstructive Lung Disease (GOLD) strategy added the St. George's Respiratory Questionnaire (SGRQ) as the fourth possible symptoms measure. The impact of the suggested tools for symptoms of COPD and the different definitions of future risk on the frequency distribution and clinical characteristics of the GOLD groups remain unknown. Methods: Demographic and clinical characteristics were assessed in 542 patients with COPD (57.7% male, age 64.6 [9.0] years, FEV₁ 54.7 [22.3]% predicted). Health status was assessed by the COPD-specific SGRQ and symptoms of anxiety and depression by the Hospital Anxiety and Depression Scale, anxiety (HADS-A) and depression (HADS-D) subscale. Cohen's Kappa was used to assess agreement between groups. Results: Level of agreement in frequency distribution using the modified Medical Research Council dyspnea (mMRC) scale ≥2, COPD Assessment Test (CAT) ≥10, Clinical COPD Questionnaire (CCQ) ≥1 and SGRQ ≥25 was moderate to very good. Best agreement was reached between CCQ and SGRQ (К = 0.838 or 0.851, p<0.001). Patients classified in mMRC GOLD A reported higher SGRQ scores, higher HADS-A and HADS-D scores compared to patients classified in CAT GOLD A or SGRQ GOLD A. Outcomes were comparable between the risk assessment groups. Conclusions: Choice of the symptom measure impacts GOLD groups more than choice of the exacerbation risk assessment. Health care professionals should be aware that patients are heterogeneous in terms of health status and symptoms of anxiety and depression based on the symptom measure used.

Metabolic load during strength training or NMES in individuals with COPD: results from the DICES trial

Background

Strength training and neuromuscular electrical stimulation (NMES) are effective training modalities for improving muscle function, exercise performance and health status in individuals with COPD. The aim of the present study was to analyze the metabolic load of these training modalities at baseline, half-way, and at the end of an eight-week interdisciplinary pulmonary rehabilitation program in a subgroup of individuals with COPD of the DICES trial.

Methods

Of 24 individuals with COPD (FEV₁: 34 ± 2% predicted, men: 58%, age: 66 (61–68) years), peak oxygen uptake (VO₂), peak minute ventilation (V_E), heart rate, oxygen saturation and symptom scores were assessed during HF-NMES (75 Hz), LF-NMES (15 Hz) and strength training at three moments during their pulmonary rehabilitation program.

Results

Intervention-related peak VO₂ did not change over time during HF-NMES, LF-NMES or strength training. Intervention-related peak V_E did not change over time during strength training or LF-NMES and increased slightly, but significantly over time during HF-NMES. Peak VO₂ and V_E were significantly higher during strength training compared to HF-NMES or LF-NMES. Oxygen saturation significantly decreased after the first measurements during HF-NMES and strength training group to baseline, while no significant changes in oxygen saturation were observed during the other measurements. Heart rate significantly increased compared to baseline in all groups at all moments and was significantly higher after strength training compared to HF-NMES or LF-NMES. Median end scores (points) for dyspnea, fatigue and muscle pain ranged from 1 to 3, from 0.5 to 2 and from 0 to 6 after HF-NMES, from 2 to 3, from 2 to 5 and from 0 to 9 after LF-NMES and from 2 to 5, from 1.5 to 4 and from 0 to 28 after strength training respectively.

Conclusions

To conclude, the metabolic load and symptom scores remain acceptable low over time with increasing training loads during HF-NMES, LF-NMES or strength training.

Trial registration

Trial registration:NTR2322

Determinants of 1-year changes in disease-specific health status in patients with advanced chronic obstructive pulmonary disease: A 1-year observational study

We aimed to identify baseline and longitudinal determinants of change in disease-specific health status in patients with advanced chronic obstructive pulmonary disease (COPD). Demographic and clinical characteristics as well as disease-specific health status (St George's Respiratory Questionnaire, SGRQ) were assessed in 105 outpatients with advanced COPD at baseline and at 4, 8 and 12 months. Eighty-five patients (81.0%) had complete SGRQ data at baseline and 12 months and were included in analyses. Stepwise multiple regression analysis revealed that lower SGRQ total score, higher depression scores and longer time needed to complete the Timed Up and Go (TUG) test at baseline, as well as increase in time needed to complete the TUG test and increase in dyspnoea during the 1-year follow-up period, were predictors of deterioration in disease-specific health status. The current study reinforces the stimulation of physical mobility and the targeting of dyspnoea as components for treatment programs to optimize disease-specific health status in patients with advanced COPD.

The COgnitive-Pulmonary Disease (COgnitive-PD) study: protocol of a longitudinal observational comparative study on neuropsychological functioning of patients with COPD

INTRODUCTION

Intact cognitive functioning is necessary for patients with chronic obstructive pulmonary disease (COPD) to understand the value of healthy lifestyle guidelines, to make informed decisions and subsequently act on it. Nevertheless, brain abnormalities and cognitive impairment have been found in patients with COPD. To date, it remains unknown which cognitive domains are affected and what the possible consequences are of cognitive impairment. Therefore, objectives of the study described are to determine neuropsychological functioning in patients with COPD, and its influence on health status, daily functioning and pulmonary rehabilitation outcome. Furthermore, structural and functional brain abnormalities and the relationship with cognitive and daily functioning will be explored.

METHODS AND ANALYSIS

A longitudinal observational comparative study will be performed in 183 patients with COPD referred for pulmonary rehabilitation and in 90 healthy control participants. Demographic and clinical characteristics, activities of daily living and knowledge about COPD will be assessed. Baseline cognitive functioning will be compared between patients and controls using a detailed neuropsychological testing battery. An MRI substudy will be performed to compare brain abnormalities between 35 patients with COPD with cognitive impairment and 35 patients with COPD without cognitive impairment. Patients will be recruited between November 2013 and November 2015.

ETHICS AND DISSEMINATION

The study has been approved by the Medical Ethics Committee of the University Hospital Maastricht and Maastricht University (NL45127.068.13/METC 13-3-035) and is registered in the Dutch trial register. All participants will provide written informed consent and can withdraw from the study at any point in time. Assessment and home visit data material will be managed anonymously. The results obtained can be used to optimise patient-oriented treatment for cognitively impaired patients with COPD. The findings will be disseminated in international peer-reviewed journals and through research conferences.

The relationship between coping styles and clinical outcomes in patients with COPD entering pulmonary rehabilitation

BACKGROUND

Symptoms of anxiety, depression and exercise intolerance contribute to an impaired health status in patients with Chronic Obstructive Pulmonary Disease (COPD). Coping styles may also be related to symptoms and health status. Objectives of this study were to assess the distribution of coping styles in patients entering pulmonary rehabilitation (PR) with and without anxiety and/or depression; and to assess whether coping styles contribute to exercise intolerance and reduced health status.

METHODS

Coping styles were studied in 698 patients using the Utrecht Coping List (UCL). Disease-specific health status (St. George's Respiratory Questionnaire, SGRQ), anxiety and depression (Hospital Anxiety and Depression Scale, HADS), exercise tolerance (6-minute walking distance, 6MWD) and clinical characteristics were assessed.

RESULTS

High levels (16.5%) of active confronting coping style were rarely reported. A minority of patients used low levels (17.5%) of passive reaction pattern coping style. Differences in coping profiles were present between patients with and without anxiety and/or depression. A higher level of active confronting coping style was associated with a higher 6MWD (Beta 0.092, p < 0.01), while a higher level of avoidance coping style was associated with a lower 6MWD (Beta -0.074, p = 0.017). The UCL subscales were not related to SGRQ total score (p > 0.05).

CONCLUSIONS

In COPD patients entering PR, coping styles were associated with symptoms of anxiety, depression and exercise intolerance, but not associated with disease-specific health status. Future studies should examine whether interventions aiming at optimizing coping styles during PR can improve outcomes for patients with COPD.

Evaluation of activity limitation in patients with idiopathic pulmonary fibrosis grouped according to Medical Research Council dyspnea grade

OBJECTIVE

To investigate the relations between Medical Research Council (MRC) dyspnea grade and peripheral muscle force, activities of daily living (ADL) performance, health status, lung function, and exercise capacity in subjects with idiopathic pulmonary fibrosis (IPF).

DESIGN

Prospective cross-sectional observational study.

SETTING

University hospital.

PARTICIPANTS

Subjects with IPF (N=65, 46 men) in a stable clinical state with a mean age of 68±7 years.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Right ventricular systolic pressure (RVSP) via transthoracic echocardiography, pulmonary function, isometric quadriceps force (QF) and handgrip force (HF), 6-minute walk distance (6MWD), ADL score, and health status (Medical Outcomes Study 36-Item Short-Form Health Survey [SF-36]) were assessed and compared between subjects grouped according to MRC grade.

RESULTS

Of the participants, 16 were in MRC grade 2, 17 were in MRC grade 3, 17 were in MRC grade 4, and 15 were in MRC grade 5. RVSP, pulmonary function, QF, HF, 6MWD, ADL, and SF-36 scores decreased with increasing MRC grade (all P<.001). All measures were lower (P<.05) in subjects with grades 4 and 5 than subjects with grades 2 and 3. Strong associations were found between MRC grade and 6MWD (ρ=-.89, P=.001) and ADL score (ρ=-.82, P=.001). MRC grade was also associated with RVSP, pulmonary function, QF, and HF (all ρ≥.56, P=.001).

CONCLUSIONS

The MRC dyspnea scale provides a simple and useful method of categorizing individuals with IPF with respect to their activity limitation and may assist in understanding the impact of IPF on an individual.

Efficacy of lower-limb muscle training modalities in severely dyspnoeic individuals with COPD and quadriceps muscle weakness: results from the DICES trial

RATIONALE

Strength training and neuromuscular electrical stimulation (NMES) improve lower-limb muscle function in dyspnoeic individuals with chronic obstructive pulmonary disease (COPD). However, high-frequency NMES (HF-NMES) and strength training have never been compared head-to-head; and effects of low-frequency NMES (LF-NMES) have never been studied in COPD. Therefore, the optimal training modality to improve lower-limb muscle function, exercise performance and other patient-related outcomes in individuals with severe COPD remains unknown.

OBJECTIVES

To study prospectively the efficacy of HF-NMES (75 Hz), LF-NMES (15 Hz) or strength training in severely dyspnoeic individuals with COPD with quadriceps muscle weakness at baseline.

METHODS

120 individuals with COPD (FEV1: 33±1% predicted, men: 52%, age: 64.8±0.8 years) were randomised to HF-NMES, LF-NMES or strength training as part of a comprehensive inpatient pulmonary rehabilitation programme. No treadmill walking or stationary cycling was provided.

MEASUREMENTS AND MAIN RESULTS

Groups were comparable at baseline. Quadriceps muscle strength increased after HF-NMES (+10.8 Newton-metre (Nm)) or strength training (+6.1 Nm; both p<0.01), but not after LF-NMES (+1.4 Nm; p=0.43). Quadriceps muscle endurance, exercise performance, lower-limb fat-free mass, exercise-induced symptoms of dyspnoea and fatigue improved significantly compared with baseline after HF-NMES, LF-NMES or strength training. The increase in quadriceps muscle strength and muscle endurance was greater after HF-NMES than after LF-NMES.

CONCLUSIONS

HF-NMES is equally effective as strength training in severely dyspnoeic individuals with COPD and muscle weakness in strengthening the quadriceps muscles and thus may be a good alternative in this particular group of patients. HF-NMES, LF-NMES and strength training were effective in improving exercise performance in severely dyspnoeic individuals with COPD and quadriceps weakness.

TRIAL REGISTRATION

NTR2322.

An official American Thoracic Society/European Respiratory Society statement: key concepts and advances in pulmonary rehabilitation

BACKGROUND

Pulmonary rehabilitation is recognized as a core component of the management of individuals with chronic respiratory disease. Since the 2006 American Thoracic Society (ATS)/European Respiratory Society (ERS) Statement on Pulmonary Rehabilitation, there has been considerable growth in our knowledge of its efficacy and scope.

PURPOSE

The purpose of this Statement is to update the 2006 document, including a new definition of pulmonary rehabilitation and highlighting key concepts and major advances in the field.

METHODS

A multidisciplinary committee of experts representing the ATS Pulmonary Rehabilitation Assembly and the ERS Scientific Group 01.02, "Rehabilitation and Chronic Care," determined the overall scope of this update through group consensus. Focused literature reviews in key topic areas were conducted by committee members with relevant clinical and scientific expertise. The final content of this Statement was agreed on by all members.

RESULTS

An updated definition of pulmonary rehabilitation is proposed. New data are presented on the science and application of pulmonary rehabilitation, including its effectiveness in acutely ill individuals with chronic obstructive pulmonary disease, and in individuals with other chronic respiratory diseases. The important role of pulmonary rehabilitation in chronic disease management is highlighted. In addition, the role of health behavior change in optimizing and maintaining benefits is discussed.

CONCLUSIONS

The considerable growth in the science and application of pulmonary rehabilitation since 2006 adds further support for its efficacy in a wide range of individuals with chronic respiratory disease.

Heterogeneity in clinical characteristics and co-morbidities in dyspneic individuals with COPD GOLD D: findings of the DICES trial

INTRODUCTION

Chronic obstructive pulmonary disease (COPD) is a complex and heterogeneous respiratory disease with important extra-pulmonary features and comorbidities. The aim of this study was to assess clinical heterogeneity in a well-defined subgroup of individuals with COPD GOLD D, including possible gender differences.

METHODS

Pulmonary function, arterial blood gases, exercise performance, quadriceps muscle function, problematic activities of daily life, dyspnea, health status and comorbidities have been assessed in 117 individuals with a MRC dyspnea grade 4/5 and COPD GOLD D entering pulmonary rehabilitation.

RESULTS

A broad range of values were found for diffusion capacity, exercise capacity, quadriceps muscle function and health status. Indeed, the high coefficients of variation were found for these outcomes. Problematic activities of daily life as well as objectified comorbidities also varied to a great extent. Moreover, significant gender differences were found for exercise performance, lower-limb muscle function and various comorbidities.

CONCLUSION

The current findings emphasize that COPD is a heterogeneous disease whose clinical presentation varies significantly, even in individuals with very severe COPD with the same degree of dyspnea and all classified as GOLD D.

TRIAL REGISTRATION

NTR2322.

Coping styles in patients with COPD before and after pulmonary rehabilitation

INTRODUCTION

Pulmonary rehabilitation (PR) improves physical and psychological symptoms in COPD patients. Patients' coping with daily symptoms and limitations may have more influence on important patient-centred outcomes than the impaired lung function. To date, it remains unknown whether and to what extent coping styles change following PR, and whether coping styles are associated with the outcomes of a comprehensive PR.

METHODS

Coping styles were assessed in 303 COPD patients before and after a PR programme using the Utrecht Coping List (UCL). Additionally, lung function, St. George's Respiratory Questionnaire (SGRQ), Hospital Anxiety and Depression Scale, anxiety (HADS-A) and depression (HADS-D) subscales and six-minute walking distance (6MWD) were recorded.

RESULTS

The level of active confronting coping style increased (p < 0.05), whereas the levels of avoidance (p < 0.05), passive reaction pattern and reassuring thoughts coping styles decreased following PR (both p < 0.001). More than 50% of the patients changed their level of active confronting, passive reaction pattern or expressing emotions coping style. Coping styles and/or changes in coping styles after PR were related to changes in exercise tolerance, anxiety and depression, but were not related to changes in health status. Following PR, SGRQ total score, HADS-A and HADS-D scores decreased (all p < 0.001), while 6MWD increased (p < 0.05).

CONCLUSION

Comprehensive PR results in change in coping styles of COPD patients. Coping styles are related to improvements in exercise tolerance, anxiety and depression, but they are not related with changes in health status after PR. Further studies are needed to evaluate the outcome of interventions actively targeting coping styles.

Correlations between disease-specific and generic health status questionnaires in patients with advanced COPD: a one-year observational study

Background

Longitudinal studies analyzing the correlations between disease-specific and generic health status questionnaires at different time points in patients with advanced COPD are lacking. The aim of this study was to determine whether and to what extent a disease-specific health status questionnaire (Saint George’s Respiratory Questionnaire, SGRQ) correlates with generic health status questionnaires (EuroQol-5-Dimensions, EQ-5D; Assessment of Quality of Life instrument, AQoL; Medical Outcomes Study 36-Item Short-Form Health Survey, SF-36) at four different time points in patients with advanced COPD; and to determine the correlation between the changes in these questionnaires during one-year follow-up.

Methods

Demographic and clinical characteristics were assessed in 105 outpatients with advanced COPD at baseline. Disease-specific health status (SGRQ) and generic health status (EQ-5D, AQoL, SF-36) were assessed at baseline, four, eight, and 12 months. Correlations were determined between SGRQ and EQ-5D, AQoL, and SF-36 scores and changes in these scores. Agreement in direction of change was assessed.

Results

Eighty-four patients (80%) completed one-year follow-up and were included for analysis. SGRQ total score and EQ-5D index score, AQoL total score and SF-36 Physical Component Summary measure (SF-36 PCS) score were moderately to strongly correlated. The correlation of the changes between the SGRQ total score and EQ-5D index score, AQoL total score, SF-36 PCS, and SF-36 Mental Component Summary measure (SF-36 MCS) score were weak or absent. The direction of changes in SGRQ total scores agreed slightly with the direction of changes in EQ-5D index score, AQoL total score, and SF-36 PCS score.

Conclusions

At four, eight and 12 months after baseline, SGRQ total scores and EQ-5D index scores, AQoL total scores and SF-36 PCS scores were moderately to strongly correlated, while SGRQ total scores were weakly correlated with SF-36 MCS scores. The correlations between changes over time were weak or even absent. Disease-specific health status questionnaires and generic health status questionnaires should be used together to gain complete insight in health status and changes in health status over time in patients with advanced COPD.

Effects of body mass index on task-related oxygen uptake and dyspnea during activities of daily life in COPD

BACKGROUND

Patients with COPD use a higher proportion of their peak aerobic capacity during the performance of domestic activities of daily life (ADLs) compared to healthy peers, accompanied by a higher degree of task-related symptoms. To date, the influence of body mass index (BMI) on the task-related metabolic demands remains unknown in patients with COPD. Therefore, the aim of our study was to determine the effects of BMI on metabolic load during the performance of 5 consecutive domestic ADLs in patients with COPD.

METHODOLOGY

Ninety-four COPD patients and 20 healhty peers performed 5 consecutive, self-paced domestic ADLs putting on socks, shoes and vest; folding 8 towels; putting away groceries; washing up 4 dishes, cups and saucers; and sweeping the floor for 4 min. Task-related oxygen uptake and ventilation were assessed using a mobile oxycon, while Borg scores were used to assess task-related dyspnea and fatigue.

PRINCIPAL FINDINGS

1. Relative task-related oxygen uptake after the performance of domestic ADLs was increased in patients with COPD compared to healthy elderly, whereas absolute oxygen uptake is similar between groups; 2. Relative oxygen uptake and oxygen uptake per kilogram fat-free mass were comparable between BMI groups; and 3. Borg symptom scores for dyspnea en fatigue were comparable between BMI groups.

CONCLUSION

Patients with COPD in different BMI groups perform self-paced domestic ADLs at the same relative metabolic load, accompanied by comparable Borg symptom scores for dyspnea and fatigue.

Differences in walking pattern during 6-min walk test between patients with COPD and healthy subjects

Background

To date, detailed analyses of walking patterns using accelerometers during the 6-min walk test (6MWT) have not been performed in patients with chronic obstructive pulmonary disease (COPD). Therefore, it remains unclear whether and to what extent COPD patients have an altered walking pattern during the 6MWT compared to healthy elderly subjects.

Methodology/Principal Findings

79 COPD patients and 24 healthy elderly subjects performed the 6MWT wearing an accelerometer attached to the trunk. The accelerometer features (walking intensity, cadence, and walking variability) and subject characteristics were assessed and compared between groups. Moreover, associations were sought with 6-min walk distance (6MWD) using multiple ordinary least squares (OLS) regression models. COPD patients walked with a significantly lower walking intensity, lower cadence and increased walking variability compared to healthy subjects. Walking intensity and height were the only two significant determinants of 6MWD in healthy subjects, explaining 85% of the variance in 6MWD. In COPD patients also age, cadence, walking variability measures and their interactions were included were significant determinants of 6MWD (total variance in 6MWD explained: 88%).

Conclusions/Significance

COPD patients have an altered walking pattern during 6MWT compared to healthy subjects. These differences in walking pattern partially explain the lower 6MWD in patients with COPD.

Progression of osteoporosis in patients with COPD: a 3-year follow up study

Currently, our knowledge on the progression of osteoporosis and its determinants is limited in patients with chronic obstructive pulmonary disease (COPD). Bone mineral density generally remains stable in patients with COPD over a period of 3 years. Nevertheless, the progression of vertebral fractures was not assessed, while an increase of vertebral fractures over time may be reasonable. Aims of the current study were to determine the percentage of newly diagnosed osteoporotic patients after a follow up of 3 years and to identify baseline risk factors for the progression of osteoporosis in COPD. Clinically stable COPD outpatients were included. Lung function parameters, body composition measures, six minute walk distance, DXA-scan and X-spine were assessed at baseline and repeated after 3 years. Prevalence of osteoporosis in COPD patients increased from 47% to 61% in 3 years mostly due to an increase of vertebral fractures. Lower baseline T-score at the trochanter independently increased the risk for the development of osteoporosis. Additionally, baseline vitamin D deficiency increased this risk 7.5-fold. In conclusion, the prevalence of osteoporosis increased over a 3-year period in patients with COPD. Baseline risk factors for the development of osteoporosis are osteopenia at the trochanter and vitamin D deficiency.

Frequency and relevance of ischemic electrocardiographic findings in patients with chronic obstructive pulmonary disease

Cardiovascular disease is common in patients with chronic obstructive pulmonary disease (COPD) but often remains unrecognized. Ischemic electrocardiographic (ECG) changes are associated with a higher risk of dying from coronary heart disease but have never been systematically evaluated in COPD. Also, their relation to clinical outcome has not been studied. We aimed to determine the frequency of ischemic ECG changes and its relevance in relation to clinical outcome and predictors of impaired survival in patients with COPD. Clinical characteristics, pulmonary function, and co-morbidities were assessed in 536 patients with COPD during baseline assessment of a comprehensive pulmonary rehabilitation program. Moreover, electrocardiograms at rest were obtained in all patients. All electrocardiograms were scored independently by 2 cardiologists using the Minnesota scoring system. Major or minor Q or QS pattern, ST junction and segment depression, T-wave items, or left bundle branch block were considered ischemic ECG changes. One hundred thirteen patients (21%) had ischemic ECG changes. Moreover, 42 of 293 patients (14%) without self-reported cardiovascular co-morbidities had ischemic ECG changes. In addition, patients with ischemic ECG changes had higher dyspnea grades (Modified Medical Research Council (mMRC) 2.9 ± 1.1 vs 2.6 ± 1.1, p = 0.032), worse exercise performance (6-minute walking distance 387 ± 126 vs 425 ± 126 m, p = 0.004), more systemic inflammation (high-sensitivity C-reactive protein 11.2 ± 16.2 vs 7.9 ± 10.7 mmol/l, p = 0.01), higher scores on the Charlson Co-morbidity Index (1.8 ± 0.9 vs 1.5 ± 0.8 points), and higher scores BODE (5.3 ± 3.7 vs 4.5 ± 3.4 points, p = 0.033) and on ADO indexes (5.2 ± 1.7 vs 4.8 ± 1.7 points, p = 0.029) compared to patients without ischemic ECG changes, whereas forced expiratory volume in the first second was similar (40.8 ± 15.2% vs 42.6% ± 15.9%, p = 0.30). In conclusion, ischemic ECG changes are common in patients with COPD and associated with poor clinical outcome irrespective of forced expiratory volume in the first second. These results suggest an important role for cardiovascular disease in impaired survival in these patients.

Impaired health status and care dependency in patients with advanced COPD or chronic heart failure

PURPOSE

Aims of this cross-sectional study were to assess health status and care dependency in patients with advanced chronic obstructive pulmonary disease (COPD) or chronic heart failure (CHF) and to identify correlates of an impaired health status.

METHODS

The following outcomes were assessed in outpatients with advanced COPD (n = 105) or CHF (n = 80): clinical characteristics; general health status (EuroQol-5 Dimensions (EQ-5D); Assessment of Quality of Life instrument (AQoL); Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36)); disease-specific health status (St. Georges Respiratory Questionnaire (SGRQ), Minnesota Living with Heart Failure Questionnaire (MLHFQ)); physical mobility (timed 'Up and Go' test); and care dependency (Care Dependency Scale).

RESULTS

Patients with advanced COPD or CHF have an impaired health status and may be confronted with care dependency. Multiple regression analyses have shown that physical and psychological symptoms, care dependency and number of drugs were correlated with impaired health status in advanced COPD or CHF, while demographic and clinical characteristics like age, gender, disease severity and co-morbidities were not correlated.

CONCLUSIONS

Clinical care should regularly assess symptom burden and care dependency to identify patients with advanced COPD or CHF at risk for an impaired health status.

Responsiveness of three instruments to assess self-reported functional status in patients with COPD

The study aimed to compare the responsiveness of three instruments to assess self-reported changes in functional status after exercise training in patients with COPD: Pulmonary Functional Status and Dyspnea Questionnaire -modified version (PFSDQ-M), London Chest Activity of Daily Living (LCADL) and Medical Research Council scale (MRC). Twenty-two patients (11 female, 66[62-71] years, FEV1 42[33-61]%predicted) participated in a 3-month high-intensity exercise program. The three instruments were applied pre- and post-program, as well as assessment of lung function, muscle strength, exercise capacity (6-minute walking test, 6MWT) and quality of life (St. George's Respiratory Questionnaire, SGRQ). SGRQ, 6MWT and quadriceps femoris, biceps and triceps brachialis strength improved significantly after the program (p < 0.05 for all). Training also yielded significant improvement in the LCADL total score and self-care, domestic and leisure domains and in the PFSDQ-M 'change in activities' domain, with no improvement in the MRC (p = 0.11). Calculation of effects sizes also indicated higher responsiveness in the LCADL than the other instruments. There were no significant correlations between changes in the three instruments and changes in lung function, SGRQ or 6MWT. In conclusion, PFSDQ-M's 'change in activity' domain and specially the LCADL (to a higher extent) showed responsiveness to detect changes in functional status after three months of high-intensity exercise training in patients with COPD, whereas the MRC scale did not. In this population, the improvement in functional status was not related with improvement in exercise capacity, lung function or quality of life.

Task-related oxygen uptake and symptoms during activities of daily life in CHF patients and healthy subjects

Patients with chronic heart failure (CHF) have a significantly lower peak aerobic capacity compared to healthy subjects, and, may therefore experience more inconvenience during the performance of domestic activities of daily life (ADLs). To date, the extent to which task-related oxygen uptake, heart rate, ventilation and symptoms during the performance of ADLs in CHF patients is different than in healthy subjects remains uncertain. General demographics, pulmonary function, body composition and peak aerobic capacity were assessed in 23 CHF outpatients and 20 healthy peers. In addition, the metabolic requirement of five simple self-paced domestic ADLs was assessed using a mobile oxycon. Task-related oxygen uptake (ml/min) was similar or lower in CHF patients compared to healthy subjects. In contrast, patients with CHF performing ADLs consumed oxygen at a higher proportion of their peak aerobic capacity than healthy subjects (p < 0.05). For example, getting dressed resulted in a mean task-related oxygen uptake of 49% of peak aerobic capacity, while sweeping the floor resulted in a mean task-related oxygen uptake of 52% of peak aerobic capacity, accompanied by significantly higher Borg symptom scores for dyspnea and fatigue (p < 0.05). Patients with CHF experience use a higher proportion of their peak aerobic capacity, peak ventilation and peak heart rate during the performance of simple self-paced domestic ADL than their healthy peers. These findings represent a necessary step in improving our understanding of improving what troubles patients the most—not being able to do the things that they could when they were healthy.

Symptoms of anxiety and depression in COPD patients entering pulmonary rehabilitation

Chronic obstructive pulmonary disease (COPD) patients may suffer from symptoms of anxiety and depression. Whether and to what extent symptoms of anxiety and depression may be present in COPD patients entering pulmonary rehabilitation and which patient characteristics are associated with psychological distress remains currently unknown. The objective of the present study is to determine the prevalence and the determinants of clinically relevant symptoms of anxiety and depression in COPD patients entering pulmonary rehabilitation. Symptoms of anxiety and depression have been assessed in 701 COPD patients entering pulmonary rehabilitation using the Hospital Anxiety and Depression Scale. Additionally, disease-specific health status, pulmonary function, body composition, exercise capacity, co-existing morbidities, smoking status, symptoms, long-term oxygen therapy and the use of antidepressant and anxiolytic drugs have been recorded. Patients had mean anxiety scores of 7.6 points and mean depression scores of 7.2 points. Anxiety scores >or=10 points were present in 225 patients (32%) and depression scores >or=10 points were present in 192 patients (27%). Patients at risk of having symptoms of anxiety were female or used antidepressant or anxiolytic drugs. Patients at risk of having symptoms of depression experienced dyspnea, had a body mass index (BMI) <21 kg/m(2) or used antidepressant or anxiolytic drugs. A considerable proportion of the COPD patients entering pulmonary rehabilitation report symptoms of anxiety and/or depression, which may significantly impair disease-specific health status. Patients at risk of having symptoms of anxiety and/or depression are female, experience dyspnea, have a low BMI or use antidepressant and/or anxiolytic drugs.

Oxygen uptake, ventilation, and symptoms during low-frequency versus high-frequency NMES in COPD: a pilot study

Transcutaneous neuromuscular electrical stimulation (NMES) involves the application of an electrical current through electrodes placed on the skin over the targeted muscles. During high-frequency NMES (HF-NMES), oxygen uptake, minute ventilation, and the degree of symptom perception (dyspnea and fatigue) have been shown to be acceptable in chronic obstructive pulmonary disease (COPD). Currently, oxygen uptake and ventilation load have never been assessed during low-frequency NMES (LF-NMES) of the lower-limb muscles. The purpose of this study was to compare prospectively oxygen uptake, ventilation, and symptom perception during a single session of LF-NMES versus a single session of HF-NMES of quadriceps muscles in patients with COPD. In 17 COPD patients (mean FEV(1) = 45% predicted, mean body mass index = 26.2 kg/m(2)), peak exercise capacity, functional exercise capacity, and the Medical Research Council dyspnea grade were evaluated. In addition, oxygen uptake, minute ventilation, heart rate, and Borg symptom scores were assessed during one session of LF-NMES (15 Hz) and one session of HF-NMES (75 Hz) and compared with peak values. Mean oxygen uptake (LF-NMES: 327 ml/min vs. HF-NMES: 315 ml/min), minute ventilation (LF-NMES: 14 L vs. HF-NMES: 15 L), and heart rate (LF-NMES: 86 BPM vs. HF-NMES: 83 BPM) were similar during both NMES frequencies. Patients used a relatively low proportion of their peak aerobic capacity during both NMES sessions (LF-NMES: 34% vs. HF-NMES: 33%; P = 0.397). In addition, symptom Borg scores for dyspnea and leg fatigue were also comparable. Oxygen uptake, ventilation, and symptoms of dyspnea and fatigue were comparable and tolerable during LF-NMES and HF-NMES in patients with COPD. Therefore, LF-NMES and HF-NMES may both be suitable rehabilitative modalities to be used in severely dyspneic patients with lower-limb muscle dysfunction.