The total-breath method yields higher values of DLCO and TLC than the conventional method

BACKGROUND

The 2017 ATS/ERS technical standard for measuring the single-breath diffusing capacity (DLCO) proposed the "rapid-gas-analyzer" (RGA) or, equivalently, "total-breath" (TB) method for the determination of total lung capacity (TLC). In this study, we compared DLCO and TLC values estimated using the TB and conventional method, and how estimated TLC using these two methods compared to that determined by body plethysmography.

METHOD

A total of 95 people with COPD (GOLD grades 1-4) and 23 healthy subjects were studied using the EasyOne Pro (ndd Medical Technologies, Switzerland) and Master Screen Body (Vyaire Medical, Höchberg, Germany).

RESULTS

On average the TB method resulted in higher values of DLCO (mean ± SD Δ = 0.469 ± 0.267; 95%CI: 0.420; 0.517 mmol*min-1*kPa-1) and TLC (Δ = 0.495 ± 0.371; 95%CI: 0.427; 0.562 L) compared with the conventional method. In healthy subjects the ratio between TB and conventional DLCO was close to one. TLC estimated using both methods was lower than that determined by plethysmography. The difference was smaller for the TB method (Δ = 1.064 ± 0.740; 95%CI: 0.929; 1.199 L) compared with the conventional method (Δ = 1.558 ± 0.940; 95%CI: 1.387; 1.739 L). TLC from body plethysmography could be estimated as a function of TB TLC and FEV1 Z-Score with an accuracy (normalized root mean square difference) of 9.1%.

CONCLUSION

The total-breath method yielded higher values of DLCO and TLC than the conventional analysis, especially in subjects with COPD. TLC from the total-breath method can also be used to estimate plethysmographic TLC with better accuracy than the conventional method. The study is registered under clinicaltrial.gov NCT04531293.

A new approach for the detection of obesity-related airway obstruction in lung-healthy individuals

BACKGROUND

Subjects with obesity show an increased prevalence of airway obstruction but it is not clear in each case whether this reflects genuine lung disease. Via intentional increase in end-expiratory lung volume we studied the detection of obesity-induced airway obstruction in lung-healthy obese subjects.

METHODS

The primary study population comprised 66 lung-healthy obese subjects and 23 normal weight subjects. Measurements were performed in a body plethysmograph allowing for recording and quantification of breathing loops in terms of specific airway resistance at both normal and intentionally elevated end-expiratory lung volume. The change in volume was documented by a shutter maneuver.

RESULTS

The voluntary increase of lung volume led to a significant reduction of expiratory airway resistance in 11 of the 66 obese subjects. This reduction could be quantified by a change of total expiratory resistance (sRtEX) of >1 kPa*s but was also clearly visible in the breathing loops. sRtEX showed the largest change among all resistance parameters. The loops of normal weight subjects remained virtually unaffected by the change in lung volume. Moreover, those of 5 obese patients with COPD who were measured for comparison partially showed a reduction of resistance but airway obstruction remained.

CONCLUSION

The proposed breathing maneuver was simple to perform and allowed for a quantitative and qualitative detection of obesity-induced airway obstruction. This might help in reducing the likelihood of misdiagnosis and overtreatment of obese patients.

Prediction of lung emphysema in COPD by spirometry and clinical symptoms: results from COSYCONET

Background

Lung emphysema is an important phenotype of chronic obstructive pulmonary disease (COPD), and CT scanning is strongly recommended to establish the diagnosis. This study aimed to identify criteria by which physicians with limited technical resources can improve the diagnosis of emphysema.

Methods

We studied 436 COPD patients with prospective CT scans from the COSYCONET cohort. All items of the COPD Assessment Test (CAT) and the St George’s Respiratory Questionnaire (SGRQ), the modified Medical Research Council (mMRC) scale, as well as data from spirometry and CO diffusing capacity, were used to construct binary decision trees. The importance of parameters was checked by the Random Forest and AdaBoost machine learning algorithms.

Results

When relying on questionnaires only, items CAT 1 & 7 and SGRQ 8 & 12 sub-item 3 were most important for the emphysema- versus airway-dominated phenotype, and among the spirometric measures FEV₁/FVC. The combination of CAT item 1 (≤ 2) with mMRC (> 1) and FEV₁/FVC, could raise the odds for emphysema by factor 7.7. About 50% of patients showed combinations of values that did not markedly alter the likelihood for the phenotypes, and these could be easily identified in the trees. Inclusion of CO diffusing capacity revealed the transfer coefficient as dominant measure. The results of machine learning were consistent with those of the single trees.

Conclusions

Selected items (cough, sleep, breathlessness, chest condition, slow walking) from comprehensive COPD questionnaires in combination with FEV₁/FVC could raise or lower the likelihood for lung emphysema in patients with COPD. The simple, parsimonious approach proposed by us might help if diagnostic resources regarding respiratory diseases are limited.

Trial registration ClinicalTrials.gov, Identifier: NCT01245933, registered 18 November 2010, https://clinicaltrials.gov/ct2/show/record/NCT01245933.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12931-021-01837-2.

The role of clinical signs and spirometry in the diagnosis of obstructive airway diseases: a systematic analysis adapted to general practice settings

Background

In general practice (GP), the diagnosis of obstructive airway diseases much relies on diagnostic questions, in view of the limited availability of lung function. We systematically assessed the relative importance of such questions for diagnosing asthma and chronic obstructive pulmonary disease (COPD), either without or with information from spirometry.

Methods

We used data obtained in a pulmonary practice to ensure the validity of diagnoses and assessments. Subjects with a diagnosis of COPD (n=260), or asthma (n=433), or other respiratory diseases (n=230), and subjects without respiratory diseases (n=364, controls) were included. The diagnostic questions comprised eight items, covering smoking history, self-attributed allergic rhinitis, dyspnea, cough, phlegm and wheeze. Optionally standard parameters of the flow-volume-curve were included. Decision trees for the diagnosis of COPD and asthma were constructed, moreover a probabilistic diagnostic network based on the results of path analyses describing the relationship between variables.

Results

In the decision trees, age, sex, current smoking, wheezing, dyspnea upon mild exertion, self-attributed allergic rhinitis, phlegm, forced expiratory volume in one second (FEV₁), and expiratory flow rates were relevant, depending on the diagnostic comparison, while cough, dyspnea upon strong exertion and ex-smoker status were not relevant. In contrast, the probabilistic network for the diagnosis of COPD and asthma versus controls incorporated all diagnostic questions, i.e., dyspnea upon mild or strong exertion, current smoking, ex-smoking, wheezing, cough and phlegm but from spirometry only FEV₁. Depending on the individual pattern, the probability for COPD could raise from 25% to 81%, while the diagnostic gain for asthma was lower.

Conclusions

The study developed simple diagnostic algorithms for asthma and COPD that take into account the relative importance of clinical signs and history, as well as spirometric data if available. The diagnostic accuracy was especially high for COPD. These algorithms may be helpful as a starting point in the standardisation of diagnostic strategies in GP practices.

Trial registration

The study is registered under DRKS00013935 at German Clinical Trials Register (DRKS, Date of registration 01/03/2018).

[Guideline for the Diagnosis and Treatment of Asthma - Addendum 2020 - Guideline of the German Respiratory Society and the German Atemwegsliga in Cooperation with the Paediatric Respiratory Society and the Austrian Society of Pneumology]

The present addendum of the guideline for the diagnosis and treatment of asthma (2017) complements new insights into the diagnosis and management of asthma as well as for the newly approved drugs for the treatment of asthma. Current, evidence-based recommendations on diagnostic and therapeutic approaches are presented for children and adolescents as well as for adults with asthma.

Withdrawal of inhaled corticosteroids versus continuation of triple therapy in patients with COPD in real life: observational comparative effectiveness study

BACKGROUND

Inhaled corticosteroids (ICS) are indicated for prevention of exacerbations in patients with COPD, but they are frequently overprescribed. ICS withdrawal has been recommended by international guidelines in order to prevent side effects in patients in whom ICS are not indicated.

METHOD

Observational comparative effectiveness study aimed to evaluate the effect of ICS withdrawal versus continuation of triple therapy (TT) in COPD patients in primary care. Data were obtained from the Optimum Patient Care Research Database (OPCRD) in the UK.

RESULTS

A total of 1046 patients who withdrew ICS were matched 1:4 by time on TT to 4184 patients who continued with TT. Up to 76.1% of the total population had 0 or 1 exacerbation the previous year. After controlling for confounders, patients who discontinued ICS did not have an increased risk of moderate or severe exacerbations (adjusted HR: 1.04, 95% confidence interval (CI) 0.94-1.15; p = 0.441). However, rates of exacerbations managed in primary care (incidence rate ratio (IRR) 1.33, 95% CI 1.10-1.60; p = 0.003) or in hospital (IRR 1.72, 95% CI 1.03-2.86; p = 0.036) were higher in the cessation group. Unsuccessful ICS withdrawal was significantly and independently associated with more frequent courses of oral corticosteroids the previous year and with a blood eosinophil count ≥ 300 cells/μL.

CONCLUSIONS

In this primary care population of patients with COPD, composed mostly of infrequent exacerbators, discontinuation of ICS from TT was not associated with an increased risk of exacerbation; however, the subgroup of patients with more frequent courses of oral corticosteroids and high blood eosinophil counts should not be withdrawn from ICS. Trial registration European Network of Centres for Pharmacoepidemiology and Pharmacovigilance (EUPAS30851).

Effect of Inhaled Corticosteroid Withdrawal on Chronic Obstructive Pulmonary Disease Exacerbations in Patients Taking Triple Therapy at Baseline

Purpose

In the Withdrawal of Inhaled Steroids during Optimized Bronchodilator Management (WISDOM) trial, inhaled corticosteroid (ICS) withdrawal in patients with chronic obstructive pulmonary disease receiving triple therapy (long-acting β₂-agonist+long-acting muscarinic antagonist+ICS) did not change moderate/severe exacerbation risk. However, many patients were not taking triple therapy before study participation. This analysis was conducted to eliminate the impact of non-ICS users on WISDOM results by re-analyzing the data using only the subset of patients who were taking triple therapy at screening.

Patients and Methods

The effect of ICS withdrawal on moderate/severe exacerbation risk in the subgroup of WISDOM patients taking triple therapy before enrolling in the study was evaluated in this post hoc analysis. Additionally, the effect of ICS withdrawal in patients with a history of ≥2 exacerbations in the previous year and various blood eosinophil counts was assessed.

Results

Overall, 39.0% (n=970: ICS continuation, 479; ICS withdrawal, 491) of the WISDOM trial population were taking triple therapy at screening. Baseline characteristics were generally similar between groups. Moderate/severe exacerbation risk between the ICS withdrawal and continuation groups (hazard ratio [HR], 1.05; 95% confidence interval [CI]: 0.89–1.25) was not increased in patients taking triple therapy at screening versus the overall trial population (HR [95% CI]: 1.06 [0.94–1.19]). However, in patients with a history of ≥2 exacerbations, exacerbation risk (HR [95% CI]) increased nominally with blood eosinophil count from 1.07 [0.81–1.41] (≥100 cells/μL) to 1.45 [0.58–3.60] (≥400 cells/μL).

Conclusion

Consistent with results from the overall WISDOM trial population, ICS withdrawal did not increase exacerbation risk in patients taking triple therapy at screening. Patients with a history of frequent exacerbations and higher blood eosinophil counts could benefit from continuation of ICS-based therapy.

Point your SmartPhone at the code above. If you have a QR code reader the video abstract will appear. Or use:

https://youtu.be/q_gF6ypMYJw

Blood eosinophils as a biomarker of future COPD exacerbation risk: pooled data from 11 clinical trials

Background

Chronic obstructive pulmonary disease (COPD) is characterised by progressive airflow limitation and chronic inflammation. Predicting exacerbations of COPD, which contribute to disease progression, is important to guide preventative treatment and improve outcomes. Blood eosinophils are a biomarker for patient responsiveness to inhaled corticosteroids (ICS); however, their effectiveness as a predictive biomarker for COPD exacerbations is unclear.

Methods

This post hoc analysis pooled data from 11 Boehringer Ingelheim-sponsored Phase III and IV randomised COPD studies with similar methodologies. Exacerbation data were collected from these studies, excluding patients from the ICS withdrawal arm of the WISDOM® study. Patients were grouped according to their baseline blood eosinophil count, baseline ICS use and number of exacerbations in the year prior to each study.

Results

Exacerbation rate data and baseline eosinophil count were available for 22,125 patients; 45.6% presented with a baseline blood eosinophil count of ≤ 150 cells/μL, 34.3% with 150–300 cells/μL and 20.1% with > 300 cells/μL. The lowest exacerbation rates were observed in patients with ≤ 150 cells/μL, with small increases in exacerbation rate observed with increasing eosinophil count. When stratified by exacerbation history, the annual rate of exacerbations for patients with 0 exacerbations in the previous year increased in line with increasing eosinophil counts (0.38 for ≤ 150 cells/μL, 0.39 for 150–300 cells/μL and 0.44 for > 300 cells/μL respectively). A similar trend was identified for patients with one exacerbation in the previous year, 0.62, 0.66 and 0.67 respectively. For patients with ≥ 2 exacerbations, exacerbation rates fluctuated between 1.02 (≤ 150 cells/μL) to 1.10 (150–300 cells/μL) and 1.07 (> 300 cells/μL). Higher exacerbation rates were noted in patients treated with ICS at baseline (range 0.75 to 0.82 with increasing eosinophil count) compared with patients not on ICS (range 0.45 to 0.49).

Conclusion

We found no clinically important relationship between baseline blood eosinophil count and exacerbation rate. Hence, the current analysis does not support the use of blood eosinophils to predict exacerbation risk; however, previous exacerbation history was found to be a more reliable predictor of future exacerbations.

Trial registration

ClinicalTrials.gov Identifiers: NCT00168844, NCT00168831, NCT00387088, NCT00782210, NCT00782509, NCT00793624, NCT00796653, NCT01431274, NCT01431287, NCT02296138 and NCT00975195.

Graphical abstract

Genuair®/Pressair® Inhaler in COPD: The Patient Perspective

This article reviews the latest data pertaining to the Genuair^®/Pressair^® device, a breath-actuated, multi-dose dry-powder inhaler with a two-step inhalation process, which is marketed for the delivery of aclidinium alone or in combination with formoterol for long-term maintenance bronchodilation treatment in chronic obstructive pulmonary disease. It contains multiple feedback mechanisms to guide effective use, and safety features to avoid double-dosing or attempted use when empty. In addition to describing the design of Genuair^®, the article will provide an update on inhaler operability and performance, focusing on recent patient preference and satisfaction studies. The evidence suggests that patients find Genuair^® easy to use, with patients requiring less training and making fewer inhalation errors than with other inhalers, and that patient satisfaction with the device is high.

[Therapy control of COPD by Eosinophilic Granulocytes?]

Symptomatic patients with COPD reporting about repeated exacerbations in their history (group D according to GOLD recommendations) are treated with dual bronchodilation (LAMA/LABA) with potential benefits from additional ICS. Eosinophils in peripheral blood are considered as potential biomarkers to predict exacerbations. > 300 cells/µL or 4 % of eosinophils in peripheral blood are recommended to treat the patients with additional ICS. In clinical practice, about 10 - 15 % of patients with COPD are classified as group D according to GOLD. < 20 % have increased eosinophils in peripheral blood. Thus, ICS therapy should be restricted to a minority of patients with COPD.

Spirometric changes during exacerbations of COPD: a post hoc analysis of the WISDOM trial

BACKGROUND

Exacerbations of chronic obstructive pulmonary disease (COPD) are associated with loss of lung function and poor outcomes for patients. However, there are limited data on the time course of changes in forced expiratory volume in 1 s (FEV₁) preceding the first reported symptom and after the start of an exacerbation.

METHODS

WISDOM was a multinational, randomized, double-blind, active-controlled, 52-week study in patients with severe-to-very severe COPD. Patients received triple therapy (long-acting muscarinic antagonist and long-acting β₂-agonist/inhaled corticosteroid [ICS]) for 6 weeks, and were randomized to continue triple therapy or stepwise withdrawal of the ICS (dual bronchodilator group). After suitable training, patients performed daily spirometry at home using a portable, battery-operated spirometer. In the present post hoc analysis, patients who continued to perform daily home spirometry and completed at least one measurement per week for a 56-day period before and after the start of a moderate or severe exacerbation were included. Missing values were imputed by linear interpolation (intermittent), backfilling (beginning) or carry forward (end). Exacerbation onset was the first day of a reported symptom of exacerbation.

RESULTS

Eight hundred and eighty-eight patients in the WISDOM study had a moderate/severe exacerbation after the complete ICS withdrawal visit; 360 of them contributed at least one FEV₁ measure per week for the 8 weeks before and after the event and are included in this analysis. Mean daily FEV₁ began to decline from approximately 2 weeks before the onset of symptoms of an exacerbation, dropping from 0.907 L (mean Days - 56 to - 36 before the exacerbation) to 0.860 L on the first day of the exacerbation. After the exacerbation, mean FEV₁ improved but did not return to pre-exacerbation levels (mean Days 36-56 after the exacerbation, 0.875 L). The pattern of FEV₁ changes around exacerbations was similar in the triple therapy and dual bronchodilator groups, and a similar pattern was seen in moderate and severe exacerbations when analysed separately.

CONCLUSIONS

Mean lung function starts to decline prior to the first reported symptoms of an exacerbation, and does not recover to pre-exacerbation levels 8 weeks after the event.

TRIAL REGISTRATION

WISDOM (ClinicalTrials.gov number, NCT00975195 ).

[Guideline for the Diagnosis and Treatment of Asthma - Guideline of the German Respiratory Society and the German Atemwegsliga in Cooperation with the Paediatric Respiratory Society and the Austrian Society of Pneumology]

The present guideline is a new version and an update of the guideline for the diagnosis and treatment of asthma, which replaces the previous version for german speaking countries from the year 2006. The wealth of new data on the pathophysiology and the phenotypes of asthma, and the expanded spectrum of diagnostic and therapeutic options necessitated a new version and an update. This guideline presents the current, evidence-based recommendations for the diagnosis and treatment of asthma, for children and adolescents as well as for adults with asthma.

Physical Activity and Fatigue in Patients with Sarcoidosis

BACKGROUND

Little is known about physical activity in daily life among patients with sarcoidosis. Fatigue is a frequent and disabling symptom that might negatively affect physical activity levels.

METHODS

In patients with sarcoidosis, we measured physical activity (steps per day) by accelerometry (SenseWear Armband) for 1 week. We assessed lung function (DLCO, FVC), exercise capacity (6-min walking distance [6MWD]), health-related quality of life (St George's Respiratory Questionnaire [SGRQ]), generic quality of life (12-Item Short-Form Health Survey [SF-12]), and fatigue (Multidimensional Fatigue Inventory [MFI-20]).

RESULTS

We investigated 57 patients with sarcoidosis (mean age 50 years, 56% male, mean DLCO 73% predicted, mean FVC 91% predicted, mean 6MWD 525 m, mean steps per day 7,490), of whom n = 14 (25%) had severe fatigue. The MFI-20 subscales "reduced activity" and "physical fatigue" were weakly associated with steps per day on a bivariate level (Spearman ρ = -0.274 and ρ = -0.277, respectively; p < 0.05), while the other subscales and the total score were not. 6MWD, SGRQ score, and SF-12 (physical health) score showed stronger associations with steps per day in bivariate analyses (Pearson r = 0.499, r = -0.386, and r = 0.467, respectively; p < 0.01), and were independent predictors of steps per day in multivariate linear regression analyses adjusting for confounders (p < 0.05). In ROC curve analyses, 6MWD, SGRQ score, and SF-12 (physical health) score properly identified sedentary patients (steps per day <5,000; AUROC 0.90, 0.81, and 0.80, respectively; p < 0.01). Fatigue was less predictive (MFI-20 subscale "general fatigue," AUROC 0.70; p = 0.03).

CONCLUSION

While exercise capacity and quality of life measurements were robust predictors of physical activity in patients with sarcoidosis, associations of objectively measured physical activity with fatigue were surprisingly weak. In sarcoidosis, fatigue might not preclude affected patients from being physically active, although this symptom is subjectively perceived as highly disabling.

Brain Activation during Perception and Anticipation of Dyspnea in Chronic Obstructive Pulmonary Disease

Background: Dyspnea is the impairing cardinal symptom in COPD, but the underlying brain mechanisms and their relationships to clinical patient characteristics are widely unknown. This study compared neural responses to the perception and anticipation of dyspnea between patients with stable moderate-to-severe COPD and healthy controls. Moreover, associations between COPD-specific brain activation and clinical patient characteristics were examined. Methods: During functional magnetic resonance imaging, dyspnea was induced in patients with stable moderate-to-severe COPD (n = 17) and healthy control subjects (n = 21) by resistive-loaded breathing. Blocks of severe and mild dyspnea were alternating, with each block being preceded by visually cued anticipation phases. Results: During the perception of increased dyspnea, both patients and controls showed comparable brain activation in common dyspnea-relevant sensorimotor and cortico-limbic brain regions. During the anticipation of increased dyspnea, patients showed higher activation in hippocampus and amygdala than controls which was significantly correlated with reduced exercise capacity, reduced health-related quality of life, and higher levels of dyspnea and anxiety. Conclusions: This study suggests that patients with stable moderate-to-severe COPD show higher activation in emotion-related brain areas than healthy controls during the anticipation, but not during the actual perception of experimentally induced dyspnea. These brain activations were related to important clinical characteristics and might contribute to an unfavorable course of the disease via maladaptive psychological and behavioral mechanisms.

Prognosis and longitudinal changes of physical activity in idiopathic pulmonary fibrosis

Background

Physical activity (PA) is associated with disease severity in idiopathic pulmonary fibrosis (IPF), but longitudinal studies evaluating its prognostic value and changes over time are lacking.

Methods

We measured PA (steps per day, SPD) in a cohort of 46 IPF-patients (mean age, 67 years; mean FVC, 76.1%pred.) by accelerometry at baseline, recorded survival status during 3 years follow-up and repeated measurements in survivors. We compared the prognostic value of PA to established mortality predictors including lung function (FVC, DLCO) and 6-min walking-distance (6MWD).

Results

During follow-up (median 34 months) 20 patients (43%) died. SPD and FVC best identified non-survivors (AUROC-curve 0.79, p < 0.01). After adjustment for confounders (sex, age, therapy), a standardized increase (i.e. one SD) in SPD, FVC%pred. or DLCO%pred. was associated with a more than halved risk of death (HR < 0.50; p < 0.01). Compared to baseline, SPD, FVC, and 6MWD annually declined in survivors by 973 SPD, 130 ml and 9 m, resulting in relative declines of 48.3% (p < 0.001), 13.3% (p < 0.001) and 7.8% (p = 0.055), respectively.

Conclusion

While PA predicts mortality of IPF patients similar to established functional measures, longitudinal decline of PA seems to be disproportionally large. Our data suggest that the clinical impact of disease progression could be underestimated by established functional measures.

Peripheral Artery Disease and Its Clinical Relevance in Patients with Chronic Obstructive Pulmonary Disease in the COPD and Systemic Consequences-Comorbidities Network Study

RATIONALE

Knowledge about the prevalence of objectively assessed peripheral artery disease (PAD) and its clinical relevance in patients with chronic obstructive pulmonary disease (COPD) is scarce.

OBJECTIVES

We aimed to: (1) assess the prevalence of PAD in COPD compared with distinct control groups; and (2) study the association between PAD and functional capacity as well as health status.

METHODS

The ankle-brachial index was used to diagnose PAD (ankle-brachial index ≤ 0.9). The 6-minute-walk distance, health status (St. George's Respiratory Questionnaire), COPD Assessment Test, and EuroQol-5-Dimensions were assessed in patients enrolled in the German COPD and Systemic Consequences-Comorbidities Network cohort study. Control groups were derived from the Study of Health in Pomerania.

MEASUREMENTS AND MAIN RESULTS

A total of 2,088 patients with COPD (61.1% male; mean [SD] age, 65.3 [8.2] years, GOLD (Global Initiative for Chronic Obstructive Lung Disease) stages I-IV: 9.4, 42.5, 37.5, and 10.5%, respectively) were included, of which 184 patients (8.8%; GOLD stage I-IV: 5.1, 7.4, 11.1, and 9.5%, respectively, vs. 5.9% in patients with GOLD stage 0 in the COPD and Systemic Consequences-Comorbidities Network) had PAD. In the Study of Health in Pomerania, PAD ranged from 1.8 to 4.2%. Patients with COPD with PAD had a significantly shorter 6-minute-walk distance (356 [108] vs. 422 [103] m, P < 0.001) and worse health status (St. George's Respiratory Questionnaire: 49.7 [20.1] vs. 42.7 [20.0] points, P < 0.001; COPD Assessment Test: 19.6 [7.4] vs. 17.9 [7.4] points, P = 0.004; EuroQol-5-Dimensions visual analog scale: 51.2 [19.0] vs. 57.2 [19.6], P < 0.001). Differences remained significant after correction for several confounders.

CONCLUSIONS

In a large cohort of patients with COPD, 8.8% were diagnosed with PAD, which is higher than the prevalence in control subjects without COPD. PAD was associated with a clinically relevant reduction in functional capacity and health status.

Plasminogen activator inhibitor-1 is elevated in patients with COPD independent of metabolic and cardiovascular function

INTRODUCTION

Plasminogen activator inhibitor-1 (PAI-1), a major inhibitor of fibrinolysis, is associated with thrombosis, obesity, insulin resistance, dyslipidemia, and premature aging, which all are coexisting conditions of chronic obstructive pulmonary disease (COPD). The role of PAI-1 in COPD with respect to metabolic and cardiovascular functions is unclear.

METHODS

In this study, which was nested within a prospective cohort study, the serum levels of PAI-1 were cross-sectionally measured in 74 stable COPD patients (Global Initiative for Chronic Obstructive Lung Disease [GOLD] Stages I-IV) and 18 controls without lung disease. In addition, triglycerides, high-density lipoprotein cholesterol, fasting plasma glucose, waist circumference, blood pressure, smoking status, high-sensitive C-reactive protein (hs-CRP), adiponectin, ankle-brachial index, N-terminal pro-B-type natriuretic peptide, and history of comorbidities were also determined.

RESULTS

The serum levels of PAI-1 were significantly higher in COPD patients than in controls, independent of a broad spectrum of possible confounders including metabolic and cardiovascular dysfunction. A multivariate regression analysis revealed triglyceride and hs-CRP levels to be the best predictors of PAI-1 within COPD. GOLD Stages II and III remained independently associated with higher PAI-1 levels in a final regression analysis.

CONCLUSION

The data from the present study showed that the serum levels of PAI-1 are higher in patients with COPD and that moderate-to-severe airflow limitation, hypertriglyceridemia, and systemic inflammation are independent predictors of an elevated PAI-1 level. PAI-1 may be a potential biomarker candidate for COPD-specific and extra-pulmonary manifestations.

Physical activity patterns and clusters in 1001 patients with COPD

We described physical activity measures and hourly patterns in patients with chronic obstructive pulmonary disease (COPD) after stratification for generic and COPD-specific characteristics and, based on multiple physical activity measures, we identified clusters of patients. In total, 1001 patients with COPD (65% men; age, 67 years; forced expiratory volume in the first second [FEV₁], 49% predicted) were studied cross-sectionally. Demographics, anthropometrics, lung function and clinical data were assessed. Daily physical activity measures and hourly patterns were analysed based on data from a multisensor armband. Principal component analysis (PCA) and cluster analysis were applied to physical activity measures to identify clusters. Age, body mass index (BMI), dyspnoea grade and ADO index (including age, dyspnoea and airflow obstruction) were associated with physical activity measures and hourly patterns. Five clusters were identified based on three PCA components, which accounted for 60% of variance of the data. Importantly, couch potatoes (i.e. the most inactive cluster) were characterised by higher BMI, lower FEV₁, worse dyspnoea and higher ADO index compared to other clusters (p < 0.05 for all). Daily physical activity measures and hourly patterns are heterogeneous in COPD. Clusters of patients were identified solely based on physical activity data. These findings may be useful to develop interventions aiming to promote physical activity in COPD.

Analysis of nocturnal actigraphic sleep measures in patients with COPD and their association with daytime physical activity

BACKGROUND

Sleep disturbances are common in patients with chronic obstructive pulmonary disease (COPD) with a considerable negative impact on their quality of life. However, factors associated with measures of sleep in daily life have not been investigated before nor has the association between sleep and the ability to engage in physical activity on a day-to-day basis been studied.

AIMS

To provide insight into the relationship between actigraphic sleep measures and disease severity, exertional dyspnoea, gender and parts of the week; and to investigate the association between sleep measures and next day physical activity.

METHODS

Data were analysed from 932 patients with COPD (66% male, 66.4±8.3 years, FEV₁% predicted=50.8±20.5). Participants had sleep and physical activity continuously monitored using a multisensor activity monitor for a median of 6 days. Linear mixed effects models were applied to investigate the factors associated with sleep impairment and the association between nocturnal sleep and patients' subsequent daytime physical activity.

RESULTS

Actigraphic estimates of sleep impairment were greater in patients with worse airflow limitation and worse exertional dyspnoea. Patients with better sleep measures (ie, non-fragmented sleep, sleeping bouts ≥225 min, sleep efficiency ≥91% and time spent awake after sleep onset <57 min) spent significantly more time in light (p<0.01) and moderate-to-vigorous physical activity (p<0.01).

CONCLUSIONS

There is a relationship between measures of sleep in patients with COPD and the amount of activity they undertake during the waking day. Identifying groups with specific sleep characteristics may be useful information when designing physical activity-enhancing interventions.

Angiopoietin-like protein 4 and cardiovascular function in COPD

Introduction

The coexistence of chronic obstructive pulmonary disease (COPD) and cardiovascular disease (CVD) is frequent and might be inter-related through inflammation-related processes reflected by specific markers. Here, we studied angiopoietin-like protein 4 (ANGPTL4), an upcoming cardiovascular marker, in stable COPD, and its relationship to cardiovascular function with respect to well-known CVD risk factors.

Methods

In a prospective COPD cohort study, we investigated serum ANGPTL4 levels, vascular status (ankle–brachial index (ABI)) and cardiac function (N-terminal pro-B-type natriuretic peptide (NT-proBNP)) as well as airflow limitation, objectively measured physical activity, the metabolic syndrome, high-sensitive C reactive protein (hs-CRP) and other CVD risk factors at 2 time points. We initially studied 74 stable COPD patients and 18 controls. For internal validation, we additionally studied 160 COPD patients of a former visit.

Results

ANGPTL4 was significantly elevated in COPD patients compared with controls (p=0.026). After correction for traditional CVD risk factors, including hs-CRP, higher levels of ANGPTL4 were independently associated with lower ABI (p=0.023) and higher NT-proBNP (p<0.001). These findings were confirmed in the internal validation analysis, which included echocardiographic assessments.

Conclusions

Serum ANGPTL4 is independently associated with cardiovascular function in COPD and might qualify as a biomarker reflecting a pathogenic link between COPD and CVD.

Daily home-based spirometry during withdrawal of inhaled corticosteroid in severe to very severe chronic obstructive pulmonary disease

The WISDOM study (NCT00975195) reported a change in lung function following withdrawal of fluticasone propionate in patients with severe to very severe COPD treated with tiotropium and salmeterol. However, little is known about the validity of home-based spirometry measurements of lung function in COPD. Therefore, as part of this study, following suitable training, patients recorded daily home-based spirometry measurements in addition to undergoing periodic in-clinic spirometric testing throughout the study duration. We subsequently determined the validity of home-based spirometry for detecting changes in lung function by comparing in-clinic and home-based forced expiratory volume in 1 second in patients who underwent stepwise fluticasone propionate withdrawal over 12 weeks versus patients remaining on fluticasone propionate for 52 weeks. Bland–Altman analysis of these data confirmed good agreement between in-clinic and home-based measurements, both across all visits and at the individual visits at study weeks 6, 12, 18, and 52. There was a measurable difference between the forced expiratory volume in 1 second values recorded at home and in the clinic (mean difference of −0.05 L), which may be due to suboptimal patient effort in performing unsupervised recordings. However, this difference remained consistent over time. Overall, these data demonstrate that home-based and in-clinic spirometric measurements were equally valid and reliable for assessing lung function in patients with COPD, and suggest that home-based spirometry may be a useful tool to facilitate analysis of changes in lung function on a day-to-day basis.

Blood eosinophil count and exacerbations in severe chronic obstructive pulmonary disease after withdrawal of inhaled corticosteroids: a post-hoc analysis of the WISDOM trial

BACKGROUND

Blood eosinophil counts might predict response to inhaled corticosteroids (ICS) in patients with chronic obstructive pulmonary disease (COPD) and a history of exacerbations. We used data from the WISDOM trial to assess whether patients with COPD with higher blood eosinophil counts would be more likely to have exacerbations if ICS treatment was withdrawn.

METHODS

WISDOM was a 12-month, randomised, parallel-group trial in which patients received 18 μg tiotropium, 100 μg salmeterol, and 1000 μg fluticasone propionate daily for 6 weeks and were then randomly assigned (1:1) electronically to receive either continued or reduced ICS over 12 weeks. We did a post-hoc analysis after complete ICS withdrawal (months 3-12) to compare rate of exacerbations and time to exacerbation outcomes on the basis of blood eosinophil subgroups of increasing cutoff levels. The WISDOM trial is registered at ClinicalTrials.gov, number NCT00975195.

FINDINGS

In the 2296 patients receiving treatment after ICS withdrawal, moderate or severe exacerbation rate was higher in the ICS-withdrawal group versus the ICS-continuation group in patients with eosinophil counts (out of total white blood cell count) of 2% or greater (rate ratio 1·22 [95% CI 1·02-1·48]), 4% or greater (1·63 [1·19-2·24]), and 5% or greater (1·82 [1·20-2·76]). The increase in exacerbation rate became more pronounced as the eosinophil cutoff level rose, with significant treatment-by-subgroup interaction reached for 4% and 5% only. Similar results were seen with eosinophil cutoffs of 300 cells per μL and 400 cells per μL, and mutually exclusive subgroups.

INTERPRETATION

Blood eosinophil counts at screening were related to the exacerbation rate after complete ICS withdrawal in patients with severe to very severe COPD and a history of exacerbations. Our data suggest that counts of 4% or greater or 300 cells per μL or more might identify a deleterious effect of ICS withdrawal, an effect not seen in most patients with eosinophil counts below these thresholds.

FUNDING

Boehringer Ingelheim.

Current thinking and new paradigm for COPD

During the 2015 European Respiratory Society Congress, a symposium was held on 'Current thinking and new paradigm for COPD'. Through a combination of plenary lectures and interactive panel discussions, experts discussed the recent evidence for chronic obstructive pulmonary disease (COPD) treatment and how this evidence can be applied in clinical practice.

Structural Brain Changes in Patients With COPD

BACKGROUND

Patients with COPD suffer from chronic dyspnea, which is commonly perceived as highly aversive and threatening. Moreover, COPD is often accompanied by disease-specific fears and avoidance of physical activity. However, little is known about structural brain changes in patients with COPD and respective relations with disease duration and disease-specific fears.

METHODS

This study investigated structural brain changes in patients with COPD and their relation with disease duration, fear of dyspnea, and fear of physical activity. We used voxel-based morphometric analysis of MRI images to measure differences in generalized cortical degeneration and regional gray matter between 30 patients with moderate to severe COPD and 30 matched healthy control subjects. Disease-specific fears were assessed by the COPD anxiety questionnaire.

RESULTS

Patients with COPD showed no generalized cortical degeneration, but decreased gray matter in posterior cingulate cortex (whole-brain analysis) as well as in anterior and midcingulate cortex, hippocampus, and amygdala (regions-of-interest analyses). Patients' reductions in gray matter in anterior cingulate cortex were negatively correlated with disease duration, fear of dyspnea, and fear of physical activity. Mediation analysis revealed that the relation between disease duration and reduced gray matter of the anterior cingulate was mediated by fear of physical activity.

CONCLUSIONS

Patients with COPD demonstrated gray matter decreases in brain areas relevant for the processing of dyspnea, fear, and antinociception. These structural brain changes were partly related to longer disease duration and greater disease-specific fears, which might contribute to a less favorable course of the disease.

Disease Progression and Changes in Physical Activity in Patients with Chronic Obstructive Pulmonary Disease

RATIONALE

Little is known about the role of physical activity in the course of chronic obstructive pulmonary disease (COPD).

OBJECTIVES

To assess changes in physical activity in COPD in relation to severity stages and changes in other disease components, and to evaluate the longitudinal association between sustained physical inactivity and disease progression.

METHODS

In this prospective cohort study, we measured physical activity (multisensory armband), airflow obstruction (FEV1), health status (St. George's Respiratory Questionnaire), exercise capacity (6-min-walk distance [6MWD]), muscle mass (fat-free mass [FFM]), and systemic inflammation (fibrinogen and high-sensitivity C-reactive protein) over a 3-year period in 137 patients with COPD and 26 with chronic bronchitis (normal spirometry).

MEASUREMENTS AND MAIN RESULTS

Independent of baseline disease severity, steps per day, total daily energy expenditure, and (daily) physical activity level (PAL) decreased by 393, 76 kcal, and 0.04 per year, respectively. The decline in PAL was significantly associated with a decline in FEV1 and an increase in St. George's Respiratory Questionnaire total score. Changes in 6MWD, FFM, and inflammatory markers were not associated with changes in PAL. Independent of FEV1, sustained physical inactivity (i.e., PAL(T0andT1)  < 1.40) was related to a greater decline in 6MWD and FFM compared with that in patients with some level of activity (i.e., PAL(T0and/orT1) ≥ 1.40; difference, 17 m/yr and 0.87 kg/yr, respectively).

CONCLUSIONS

Over time, physical activity substantially decreases across all severity stages of COPD, and this decline is paralleled by a worsening of lung function and health status. Sustained physical inactivity is associated with a progression of exercise intolerance and muscle depletion.

CXCR2 Antagonist MK-7123. A Phase 2 Proof-of-Concept Trial for Chronic Obstructive Pulmonary Disease

RATIONALE

An antagonist (MK-7123) of the cytokine receptor CXCR2 reduces neutrophil chemotaxis and thus may alleviate airway inflammation in chronic obstructive pulmonary disease (COPD).

OBJECTIVES

To assess the efficacy, safety, and tolerability of three dose levels of MK-7123, compared with placebo, in patients with moderate to severe COPD.

METHODS

This 6-month, double-blind study randomized patients with moderate to severe COPD (already on standard therapy) to daily MK-7123 at 10, 30, or 50 mg or placebo. The primary endpoint was change from baseline in post-bronchodilator FEV1.

MEASUREMENTS AND MAIN RESULTS

A total of 616 patients (71% male; mean age, 63 yr; 45% current smokers; baseline FEV1 [SD], 1.43 L [0.45]; mean FEV1 percent predicted, 43.9%) were randomized. Only MK-7123 50 mg led to significant improvement in FEV1 over placebo (mean difference [SE], 67 ml [32]). Reduced sputum neutrophil count was observed among the 122 patients examined; P = 0.003 (3 mo) and P = 0.092 (6 mo) (MK-7123 50 mg vs. placebo). The stratum of current smokers, but not that of nonsmokers, showed significant improvement versus placebo in FEV1 (168 ml) and time-to-first exacerbation, and showed numerical improvement in St. George's Respiratory Questionnaire for COPD score. MK-7123 caused a dose-dependent decrease in absolute neutrophil count (ANC) and reduced inflammatory biomarkers matrix metallopeptidase-9 and myeloperoxidase in plasma and sputum; ANC lower than 1.5 × 10(9)/L led to discontinuations with higher doses of MK-7123 (18% in the MK-7123 50-mg group vs. 1% in placebo). Plasma C-reactive protein and fibrinogen increased with MK-7123 treatment. Rates of infections at 6 months were similar in all groups.

CONCLUSIONS

Treatment with MK-7123 50 mg versus placebo led to significant improvement in FEV1 in patients with COPD, suggesting clinically important antiinflammatory effects with CXCR2 antagonism, although dose-related discontinuations were observed because of ANC decreases with MK-7123. Greater response was observed in smokers versus ex-smokers. Clinical trial registered with www.clinicaltrials.gov (NCT 01006616).

[Standardization of spirometry: 2015 update. Published by German Atemwegsliga, German Respiratory Society and German Society of Occupational and Environmental Medicine]

Spirometry is a simple test and considered the gold standard in lung function. An obstructive ventilatory defect is a disproportionate reduction of maximal airflow from the lung in relation to the maximal volume that can be displaced from the lung. It implies airway narrowing and is defined by a reduced FEV1/FVC ratio below the 5th percentile of the predicted value (lower limit of normal, LLN). A restrictive disorder may be suspected when vital capacity (FVC) is reduced and FEV1/FVC is normal. It is definitely proven, however, only by a decrease in TLC below the 5th percentile of predicted value (LLN). The measurement of TLC by body plethysmography is necessary to confirm or exclude a restrictive defect or hyperinflation of the lung when FVC is below the LLN. 2012 a task force of the ERS published new reference values based on 74,187 records from healthy non-smoking males and females from 26 countries. The new reference equations for the 3-95 age range are now available that include appropriate age-dependent mean values and lower limits of normal (LLN). This presentation aims at providing the reader with recommendations dealing with standardization and interpretation of spirometry.