A systematic review of the effects of bronchodilators on exercise capacity in patients with COPD

Enhancing COPD classification using combined quantitative computed tomography and texture-based radiomics: a CanCOLD cohort study

Background

Recent advances in texture-based computed tomography (CT) radiomics have demonstrated its potential for classifying COPD.

Methods

Participants from the Canadian Cohort Obstructive Lung Disease (CanCOLD) study were evaluated. A total of 108 features were included: eight quantitative CT (qCT), 95 texture-based radiomic and five demographic features. Machine-learning models included demographics along with texture-based radiomics and/or qCT. Combinations of five feature selection and five classification methods were evaluated; a training dataset was used for feature selection and to train the models, and a testing dataset was used for model evaluation. Models for classifying COPD status and severity were evaluated using the area under the receiver operating characteristic curve (AUC) with DeLong's test for comparison. SHapely Additive exPlanations (SHAP) analysis was used to investigate the features selected.

Results

A total of 1204 participants were evaluated (n=602 no COPD; n=602 COPD). There were no differences between the groups for sex (p=0.77) or body mass index (p=0.21). For classifying COPD status, the combination of demographics, texture-based radiomics and qCT performed better (AUC=0.87) than the combination of demographics and texture-based radiomics (AUC=0.81, p<0.05) or qCT alone (AUC=0.84, p<0.05). Similarly, for classifying COPD severity, the combination of demographics, texture-based radiomics and qCT performed better (AUC=0.81) than demographics and texture-based radiomics (AUC=0.72, p<0.05) or qCT alone (AUC=0.79, p<0.05). Texture-based radiomics and qCT features were among the top five features selected (15th percentile of the CT density histogram, CT total airway count, pack-years, CT grey-level distance zone matrix zone distance entropy, CT low-attenuation clusters) for classifying COPD status.

Conclusion

Texture-based radiomics and conventional qCT features in combination improve machine‑learning models for classification of COPD status and severity.

Pilot Study to Investigate the Benefits of the InnoSpire Go Mesh Nebulizer Compared to Jet Nebulizers in the Treatment of Stable COPD

Background: Nebulizers are widely used for the delivery of aerosols to patients with chronic obstructive pulmonary disease (COPD). The InnoSpire Go mesh nebulizer has been designed to improve upon the ease of use and convenience of existing nebulizers for the treatment of COPD. Methods: This was a pilot, single-center, randomized, open-label crossover study conducted over 2 months to investigate the use of the InnoSpire Go mesh nebulizer compared to the patient's own compressor driven jet nebulizer in ambulatory patients with stable COPD. Patient preference was assessed at the end of the study; quality of life, symptom scores, treatment time, and satisfaction were assessed at multiple points during the study. Results: Data for 17 patients were eligible for analysis, patients had a mean age of 64.6 years, and 64.7% were graded 3 on the modified Medical Research Council dyspnea scale. All patients preferred the InnoSpire Go mesh nebulizer over their own compressor driven jet nebulizer (p < 0.001). Nebulization of study drugs using the InnoSpire Go mesh nebulizer was associated with statistically significant increases in health-related quality of life over baseline (Dyspnea p = 0.003, Emotion p = 0.043, Mastery p = 0.011). A mixed model analysis of Borg dyspnea scores before and after exercise showed significantly (p = 0.043) lower scores for the InnoSpire Go mesh nebulizer compared with the compressor driven nebulizers. Patient satisfaction was statistically significantly higher for each of 10 questions covering ease of use, confidence, burden of use, satisfaction, and how well the device fit into their lifestyle. Treatment time was significantly shorter with the InnoSpire Go mesh nebulizer (p = 0.003). Conclusions: Patients preferred and were more satisfied with the InnoSpire Go mesh nebulizer. Nebulization of study drugs using the InnoSpire Go mesh nebulizer resulted in improved quality of life compared with baseline, and treatments were delivered in a shorter period than the compressor driven jet nebulizers. Clinical Trial Registration number: ClinicalTrials.gov: NCT03933462.

Evaluation of the effects of olodaterol on exercise endurance in patients with chronic obstructive pulmonary disease: results from two 6-week crossover studies

BACKGROUND

Two replicate, double-blind, placebo-controlled, 6-week crossover studies assessed the effect of the once-daily long-acting β2-agonist olodaterol 5 μg and 10 μg on constant work-rate cycle endurance in patients with moderate to very severe chronic obstructive pulmonary disease.

METHODS

Patients received placebo, olodaterol 5 μg once daily (QD) and olodaterol 10 μg QD in a randomised order for 6 weeks each, with a 2-week washout period in between. The primary end point was change in endurance time during constant work-rate cycle ergometry to symptom limitation at 75 % maximal work capacity after 6 weeks of treatment (2 h post-dose), based on log10-transformed data. Key secondary end points were inspiratory capacity at isotime and intensity of breathing discomfort at isotime.

RESULTS

151 and 157 patients were randomised and treated in Studies 1222.37 and 1222.38, respectively, with 147 and 154 being included in the full analysis sets. Mean endurance time at week 6 was increased compared to placebo by 14.0 % (Study 1222.37; p < 0.001) and 11.8 % (Study 1222.38; p < 0.01) with olodaterol 5 μg, and by 13.8 % (Study 1222.37; p < 0.001) and 10.5 % (Study 1222.38; p < 0.01) with olodaterol 10 μg. Inspiratory capacity at isotime increased with olodaterol 5 μg (Study 1222.37, 0.182 L, p < 0.0001; Study 1222.38, 0.084 L, p < 0.05) and 10 μg (Study 1222.37, 0.174 L; Study 1222.38, 0.166 L; both studies, p < 0.0001), and breathing discomfort was significantly reduced in Study 1222.37 (olodaterol 5 μg, 0.77 Borg units, p < 0.001; olodaterol 10 μg, 0.63 Borg units, p < 0.01) but not Study 1222.38.

CONCLUSIONS

These studies provide further characterisation of the efficacy of olodaterol, showing that improvements in airflow (forced expiratory volume in 1 s) are associated with increases in inspiratory capacity and improvements in exercise endurance time.

TRIAL REGISTRATIONS

NCT01040130 (1222.37) and NCT01040793 (1222.38).

Use of exercise testing in the evaluation of interventional efficacy: an official ERS statement

This document reviews 1) the measurement properties of commonly used exercise tests in patients with chronic respiratory diseases and 2) published studies on their utilty and/or evaluation obtained from MEDLINE and Cochrane Library searches between 1990 and March 2015.

Exercise tests are reliable and consistently responsive to rehabilitative and pharmacological interventions. Thresholds for clinically important changes in performance are available for several tests. In pulmonary arterial hypertension, the 6-min walk test (6MWT), peak oxygen uptake and ventilation/carbon dioxide output indices appear to be the variables most responsive to vasodilators. While bronchodilators do not always show clinically relevant effects in chronic obstructive pulmonary disease, high-intensity constant work-rate (endurance) tests (CWRET) are considerably more responsive than incremental exercise tests and 6MWTs. High-intensity CWRETs need to be standardised to reduce interindividual variability. Additional physiological information and responsiveness can be obtained from isotime measurements, particularly of inspiratory capacity and dyspnoea. Less evidence is available for the endurance shuttle walk test. Although the incremental shuttle walk test and 6MWT are reliable and less expensive than cardiopulmonary exercise testing, two repetitions are needed at baseline. All exercise tests are safe when recommended precautions are followed, with evidence suggesting that no test is safer than others.

Changes in the endurance shuttle walk test in COPD patients with chronic respiratory failure after pulmonary rehabilitation: the minimal important difference obtained with anchor- and distribution-based method

Background

Although the endurance shuttle walk test (ESWT) has proven to be responsive to change in exercise capacity after pulmonary rehabilitation (PR) for COPD, the minimally important difference (MID) has not yet been established. We aimed to establish the MID of the ESWT in patients with severe COPD and chronic hypercapnic respiratory failure following PR.

Methods

Data were derived from a randomized controlled trial, investigating the value of noninvasive positive pressure ventilation added to PR. Fifty-five patients with stable COPD, GOLD stage IV, with chronic respiratory failure were included (mean (SD) FEV₁ 31.1 (12.0) % pred, age 62 (9) y). MID estimates of the ESWT in seconds, percentage and meters change were calculated with anchor based and distribution based methods. Six minute walking distance (6MWD), peak work rate on bicycle ergometry (Wpeak) and Chronic Respiratory Questionnaire (CRQ) were used as anchors and Cohen’s effect size was used as distribution based method.

Results

The estimated MID of the ESWT with the different anchors ranged from 186–199 s, 76–82% and 154–164 m. Using the distribution based method the MID was 144 s, 61% and 137 m.

Conclusions

Estimates of the MID for the ESWT after PR showed only small differences using different anchors in patients with COPD and chronic respiratory failure. Therefore we recommend using a range of 186–199 s, 76–82% or 154–164 m as MID of the ESWT in COPD patients with chronic respiratory failure. Further research in larger populations should elucidate whether this cut-off value is also valid in other COPD populations and with other interventions.

Trial registration

ClinicalTrials.Gov (ID NCT00135538).

Electronic supplementary material

The online version of this article (doi:10.1186/s12931-015-0182-x) contains supplementary material, which is available to authorized users.

The Study of Efficacy, Tolerability and Safety of Theophylline Given Along with Formoterol Plus Budesonide in COPD

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a common disease causing significant socioeconomic burden. COPD patients, commonly smokers develop resistance to inhaled steroids attributed to deficiency of histone deacetylase 2 (HDAC2). The study of relationship between systemic inflammation and functional performance demonstrated that increased CRP level is inversely related to six minute walk distance (SMWD) and Forced Expired Volume in one second (FEV1). Theophylline restores HDAC2 activity thereby unlocking steroid resistance and potentiating inhaled corticosteroids (ICS) action culminating in reduced airway inflammation and mortality.

AIM

To study the effects of addition of Theophylline to the combination of Formoterol plus Budesonide on various objective and subjective parameters in moderate to severe COPD patients and to assess the safety profile of the combination. Setting and Study design: A single blinded, prospective, randomized, placebo controlled study at a tertiary care hospital in Jaipur, India.

MATERIALS AND METHODS

Fifty eight patients diagnosed with moderate to severe COPD were randomized into two groups. Group A patients received Formoterol 24μg plus budesonide 800μg daily in divided doses along with Theophylline while group B patients received Formoterol 24μg plus budesonide 800μg daily in divided doses along with placebo tablets. Both groups were followed up on 15th, 30th &60th day. During every visit all patients were assessed subjectively (symptom scoring) and objectively (spirometry, CRP, SMWT) and adverse effects if any were recorded. The obtained data subject to statistical analysis using"Graph pad Instat3" software.

RESULTS

Statistically significant improvement with a decline in total symptom score (p < 0.0001) was found with respect to "Night symptoms"&"SOB on rising" in group A. Theophylline group showed significant improvement in SMWD and FEV1.Mean fall in CRP was greater in Group A (not statistically significant). No side effects requiring withdrawal of drug were noted with Theophylline.

CONCLUSION

Addition of Theophylline to Formoterol plus Budesonide reduces dyspnea, improves exercise performance and pulmonary functions in moderate to severe COPD. Further studies are required to explore if reduced dosage would have equal efficacy with better safety and tolerability profile.

A-kinase anchoring proteins: cAMP compartmentalization in neurodegenerative and obstructive pulmonary diseases

The universal second messenger cAMP is generated upon stimulation of Gs protein-coupled receptors, such as the β2 -adreneoceptor, and leads to the activation of PKA, the major cAMP effector protein. PKA oscillates between an on and off state and thereby regulates a plethora of distinct biological responses. The broad activation pattern of PKA and its contribution to several distinct cellular functions lead to the introduction of the concept of compartmentalization of cAMP. A-kinase anchoring proteins (AKAPs) are of central importance due to their unique ability to directly and/or indirectly interact with proteins that either determine the cellular content of cAMP, such as β2 -adrenoceptors, ACs and PDEs, or are regulated by cAMP such as the exchange protein directly activated by cAMP. We report on lessons learned from neurons indicating that maintenance of cAMP compartmentalization by AKAP5 is linked to neurotransmission, learning and memory. Disturbance of cAMP compartments seem to be linked to neurodegenerative disease including Alzheimer's disease. We translate this knowledge to compartmentalized cAMP signalling in the lung. Next to AKAP5, we focus here on AKAP12 and Ezrin (AKAP78). These topics will be highlighted in the context of the development of novel pharmacological interventions to tackle AKAP-dependent compartmentalization.

Effects of formoterol inhaled dry powder on exercise performance in chronic obstructive pulmonary disease: a single-center, randomized, double-blind, placebo-controlled, crossover study

BACKGROUND

Inhaled bronchodilators commonly are used to reduce the work of breathing in patients with chronic obstructive pulmonary disease (COPD). The effects of bronchodilators are assessed in terms of symptom relief and/or improvements in spirometric indices. However, disability in COPD patients also is related to determinants such as exercise tolerance, which cannot be predicted on the basis of respiratory function. The effect of bronchodilators, such as inhaled beta2-agonists, on exercise performance of COPD patients needs to be tested.

OBJECTIVE

This study investigated the effects of formoterol inhaled dry powder on exercise performance assessed using the shuttle walking test (SWT) in patients with mild to moderate COPD.

METHODS

Patients having COPD with mild to moderate airway obstruction performed a pulmonary function test and an SWT before and after inhalation, on 2 consecutive days, of formoterol 12 μg or placebo, given by dry powder inhaler, according to a double-blind, placebo-controlled, crossover study design. Breathlessness was measured using the Borg scale (BS) and a visual analog scale at baseline and after an SWT.

RESULTS

Twenty patients (15 men, 5 women; mean [SD] age, 65.95 [8.32] years) were included in the study. Forced expiratory volume in 1 second (FEV1) (P = 0.009), forced mid-expiratory flow (FEF25-75) (P = 0.011), and SWT (P = 0.005) improved significantly more with formoterol than placebo. Breathlessness decreased with formoterol, but the difference compared with placebo was statistically significant only when measured using the BS (P = 0.023). In the pooled placebo and formoterol tests, changes in the SWT were unrelated to changes in FEV1 (r = 0.18) and in FEF25-75 (r = 0.31).

CONCLUSIONS

The results of this study showed that formoterol inhaled dry powder significantly improved exercise performance in patients with COPD and that this effect was at least partially independent of achieved bronchodilation. A larger cohort of patients should be studied and a more comprehensive protocol performed to verify whether the increase in exercise tolerance after administration of formoterol is related to a decrease in expiratory flow limitation during exercise and/or to systemic effects of the drug. Another issue to be clarified is whether the improvement in exercise capacity can significantly decrease disability in patients with severe COPD.

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.

Responsiveness of Various Exercise-Testing Protocols to Therapeutic Interventions in COPD

Exercise intolerance is a key element in the pathophysiology and course of Chronic Obstructive Pulmonary Disease (COPD). As such, evaluating exercise tolerance has become an important part of the management of COPD. A wide variety of exercise-testing protocols is currently available, each protocol having its own strengths and weaknesses relative to their discriminative, methodological, and evaluative characteristics. This paper aims to review the responsiveness of several exercise-testing protocols used to evaluate the efficacy of pharmacological and nonpharmacological interventions to improve exercise tolerance in COPD. This will be done taking into account the minimally important difference, an important concept in the interpretation of the findings about responsiveness of exercise testing protocols. Among the currently available exercise-testing protocols (incremental, constant work rate, or self-paced), constant work rate exercise tests (cycle endurance test and endurance shuttle walking test) emerge as the most responsive ones for detecting and quantifying changes in exercise capacity after an intervention in COPD.

Effect of theophylline on exercise capacity in COPD patients treated with combination long-acting bronchodilator therapy: a pilot study

BACKGROUND

Many patients with chronic obstructive pulmonary disease continue to experience significant functional limitation despite the use of both long-acting anticholinergic and beta-agonist inhalers. Theophylline is a widely available medication which may further improve lung function and exercise performance. Previous studies evaluating the effects of theophylline on exercise capacity in chronic obstructive pulmonary disease (COPD) have demonstrated heterogeneous results.

METHODS

We performed a randomized placebo-controlled double-blind pilot study assessing the effects of theophylline on constant load exercise duration and lung function, involving 24 COPD patients already treated with long-acting inhaled beta-agonist and long-acting anti-cholinergic bronchodilator therapy.

RESULTS

Analyzable data was available in 10 of 12 subjects in the treatment arm and 11 of 12 subjects in the control arm. Theophylline was associated with a 26.1% (95% confidence interval [CI]: -17.3-69.5) improvement in exercise duration compared to placebo. Four of 10 treated patients demonstrated an improvement in exercise duration exceeding the minimum clinically important difference of 33%, compared to 1 of 11 controls (P = 0.15). Furthermore, peak ventilation was reduced by 11.1%, (95% CI: 0.77-21.5) which may suggest improvements in gas exchange. There were no significant observed differences in resting lung function nor measures of dyspnea between the two treatment groups.

CONCLUSIONS

Our study demonstrated a trend, but not a statistically significant improvement in exercise duration and a reduction in peak ventilation with theophylline. Based on the observed mean differences and standard deviations in this pilot study, a randomized controlled trial would require 45 subjects in each arm to detect a significant change in exercise duration.

Left atrial compression and the mechanism of exercise impairment in patients with a large hiatal hernia

OBJECTIVES

The purpose of this study was to determine the association between cardiac compression and exercise impairment in patients with a large hiatal hernia (HH).

BACKGROUND

Dyspnea and exercise impairment are common symptoms of a large HH with unknown pathophysiology. Studies evaluating the contribution of cardiac compression to the pathogenesis of these symptoms have not been performed.

METHODS

We collected clinical data from a consecutive series of 30 patients prospectively evaluated with resting and stress echocardiography, cardiac computed tomography, and respiratory function testing before and after laparoscopic HH repair. Left atrial (LA), inferior pulmonary vein, and coronary sinus compression was analyzed in relation to exercise capacity (metabolic equivalents [METs] achieved on Bruce treadmill protocol).

RESULTS

Exertional dyspnea was present in 25 of 30 patients (83%) despite normal mean baseline respiratory function. Moderate to severe LA compression was qualitatively present in 23 of 30 patients (77%) on computed tomography. Right and left inferior pulmonary vein and coronary sinus compression was present in 11 of 30 (37%), 12 of 30 (40%), and 26 of 30 (87%) patients, respectively. Post-operatively, New York Heart Association functional class and exercise capacity improved significantly (number of patients in New York Heart Association functional classes I, II, III, and IV: 6, 11, 11, and 2 vs. 26, 4, 0, and 0, respectively, p < 0.001; METs [percentage predicted]: 75 ± 24% vs. 112 ± 23%, p < 0.001) and resolution of cardiac compression was observed. Absolute change in LA diameter on the echocardiogram was the only independent cardiorespiratory predictor of exercise capacity improvement post-operatively (p = 0.006).

CONCLUSIONS

We demonstrate, for the first time, marked exercise impairment and cardiac compression in patients with a large HH and normal respiratory function. After HH repair, exercise capacity improves significantly and correlates with resolution of LA compression.

Determinants of polypharmacy and compliance with GOLD guidelines in patients with chronic obstructive pulmonary disease

Background

Polypharmacy of respiratory medications is commonly observed in patients with chronic obstructive pulmonary disease (COPD). The aims of this study were to investigate determinants of polypharmacy and to study the consistency of actual respiratory drug use with current Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines in pulmonary rehabilitation candidates with COPD.

Methods

Data were extracted from the records of all patients with a diagnosis of COPD referred for pulmonary rehabilitation to CIRO+ between 2005 and 2009. Use of respiratory medications, self-reported COPD exacerbations, lung function, blood gases, exercise capacity, Medical Research Council (MRC) dyspnea grade, and St George’s Respiratory Questionnaire (SGRQ) were recorded as part of assessment of health status.

Results

In total, 1859 COPD patients of mean age (± standard deviation) 64.3 ± 9.7 years and with a forced expiratory volume in one second (FEV₁) of 44.7% ± 18.2% were included. On average, patients used 3.5 ± 1.5 respiratory medications; this number increased with increasing GOLD stage, MRC score, and SGRQ scores. FEV₁ (% predicted), SGRQ, and number of recent exacerbations were independent determinants of polypharmacy. Use of long-acting bronchodilators and inhaled corticosteroids was substantial and comparable in all GOLD stages. Use of corticosteroids was not restricted to patients with frequent exacerbations.

Conclusion

Polypharmacy of respiratory medications is common in COPD patients with persistent symptoms. In addition to severity of disease, health status is an independent predictor of polypharmacy. Actual drug use in COPD patients referred for pulmonary rehabilitation is partially inconsistent with current GOLD guidelines.

An integrative review of systematic reviews related to the management of breathlessness in respiratory illnesses

BACKGROUND

Breathlessness is a debilitating and distressing symptom in a wide variety of diseases and still a difficult symptom to manage. An integrative review of systematic reviews of non-pharmacological and pharmacological interventions for breathlessness in non-malignant disease was undertaken to identify the current state of clinical understanding of the management of breathlessness and highlight promising interventions that merit further investigation.

METHODS

Systematic reviews were identified via electronic databases between July 2007 and September 2009. Reviews were included within the study if they reported research on adult participants using either a measure of breathlessness or some other measure of respiratory symptoms.

RESULTS

In total 219 systematic reviews were identified and 153 included within the final review, of these 59 addressed non-pharmacological interventions and 94 addressed pharmacological interventions. The reviews covered in excess of 2000 trials. The majority of systematic reviews were conducted on interventions for asthma and COPD, and mainly focussed upon a small number of pharmacological interventions such as corticosteroids and bronchodilators, including beta-agonists. In contrast, other conditions involving breathlessness have received little or no attention and studies continue to focus upon pharmacological approaches. Moreover, although there are a number of non-pharmacological studies that have shown some promise, particularly for COPD, their conclusions are limited by a lack of good quality evidence from RCTs, small sample sizes and limited replication.

CONCLUSIONS

More research should focus in the future on the management of breathlessness in respiratory diseases other than asthma and COPD. In addition, pharmacological treatments do not completely manage breathlessness and have an added burden of side effects. It is therefore important to focus more research on promising non-pharmacological interventions.

Acute administration of bronchodilators on exercise tolerance in treated COPD patients

Exercise intolerance is a major feature in patients with Chronic Obstructive Pulmonary Disease (COPD). Bronchodilators increase endurance time (ET) and reduce dynamic hyperinflation (DH). We evaluated whether a single-dose of salbutamol/ipratropium + flunisolide (BD+ICS), added on top of the regular treatment, may improve ET in COPD patients. In a single-blind randomized crossover pilot trial, nebulised BD+ICS or placebo (PL) was administered 30 min before a constant load cardiopulmonary test, in 22 moderate-to-severe COPD patients (FEV₁: 53.9% pred). ET was the primary outcome measured. BD+ICS did not improve ET or VO₂ peak with respect to PL. BD+ICS increased pre-test FEV₁ and pre-test Inspiratory Capacity but did not modify DH. In a retrospective analysis, patients were divided in Improvers (N=11) and Non-Improvers (N=11) according to the difference in ET between BD+ICS and PL (> 25 s). Improvers had a worst BODE index, a higher static hyperinflation and poorer Vd/Vt ratio at peak of exercise with respect to Non-Improvers. Improvers only had a significant increase from BD+ICS on pre-test FEV₁ and IC. In conclusion, although a single-dose BD+ICS did not improve ET in COPD patients under regular treatment, a subgroup of more severe patients may have some benefit from that.

Prescribing Practices of Anticholinergic Medications and Their Association With Cognition in an Extended Care Setting

The current study examined prescribing patterns of anticholinergic (AC) medications and their association with cognitive function in 450 nondemented and nondelirious older adults hospitalized in a postacute extended care center. Participants completed a brief neuropsychological battery that included measures of general mental status, memory, judgment, and executive functioning as part of standard clinical care. An AC burden score was calculated for each participant based on medications taken the day of the testing using the Anticholinergic Drug Scale. Although use of AC medications was common, the majority of participants were taking medications with only minimal AC properties. AC burden and total number of AC medications were negatively correlated with age. AC burden was not associated with lower performance on any of the cognitive measures. In sum, current prescribing practices of AC medications are not associated with negative cognitive effects in a sample of older adults hospitalized in an extended care center.

Impact of bronchodilator therapy on exercise tolerance in COPD

Exercise tolerance is an important parameter in patients with COPD and a primary goal of treatment is to reduce dyspnea to facilitate physical activities and improve health-related quality of life. This review examines the link between expiratory flow limitation and dyspnea to explain the rationale for the use of bronchodilators and review the characteristics of different types of exercise tests, with specific focus on which tests are likely to show a response to bronchodilators. An earlier literature search of studies published up to 1999 assessed the effects of bronchodilatort therapy on dypsnea and exercise tolerance among patients with COPD. This current review examines the clinical evidence published since 1999. Thirty-one randomized studies of exercise tolerance associated with short- and long-acting beta(2)-agonists and anticholinergics were identified. Evidence for the efficacy of bronchodilators in enhancing exercise capacity is often contradictory and possibly depends on the exercise test and study methodology. However, further studies should confirm the benefit of long-acting bronchodilators in improving spontaneous everyday physical activities.

[Dyspnea and handicap in chronic obstructive pulmonary disease: interaction of their mechanisms]

Today, dyspnea in chronic obstructive pulmonary disease (COPD) is attributed to thoracic distention secondary to bronchial obstruction and hyperventilation. It inevitably occurs during exercise, even in patients with little obstruction, when they are capable of the elevated and prolonged power output that necessitates substantial hyperventilation. Exercise intolerance is due mainly to dyspnea, but muscle fatigue is also involved, especially in COPD patients who are malnourished. Deterioration of muscle function follows a substantial reduction in daily physical activity. In malnourished and hypoxemic subjects, however, responsibility for this is attributed to diverse aggravating biological processes related to chronic low-grade inflammation and to accentuated oxidative stress. The drastic diminution of physical activity results from ventilatory and muscle impairment and from symptoms that make movement painful. Improvement of ventilatory and muscle function, however, does not lead to recovery that allows sufficient physical activity. The spiral of disengagement, a morbid, psychodynamic process, accompanies chronic diseases and has the strongest effect in patients who were not highly physically active before becoming ill. Improvement of this handicap therefore requires a comprehensive management of patients, not confined to the prescription of physical activity under medical supervision. The aim is to offer diverse treatment propositions that can produce sustainable behavioral change.

Hyperinflation and its management in COPD

Chronic obstructive pulmonary disease (COPD) is characterized by poorly reversible airflow limitation. The pathological hallmarks of COPD are inflammation of the peripheral airways and destruction of lung parenchyma or emphysema. The functional consequences of these abnormalities are expiratory airflow limitation and dynamic hyperinflation, which then increase the elastic load of the respiratory system and decrease the performance of the respiratory muscles. These pathophysiologic features contribute significantly to the development of dyspnea, exercise intolerance and ventilatory failure. Several treatments may palliate flow limitation, including interventions that modify the respiratory pattern (deeper, slower) such as pursed lip breathing, exercise training, oxygen, and some drugs. Other therapies are aimed at its amelioration, such as bronchodilators, lung volume reduction surgery or breathing mixtures of helium and oxygen. Finally some interventions, such as inspiratory pressure support, alleviate the threshold load associated to flow limitation. The degree of flow limitation can be assessed by certain spirometry indexes, such as vital capacity and inspiratory capacity, or by other more complexes indexes such as residual volume/total lung capacity or functional residual capacity/total lung capacity. Two of the best methods to measure flow limitation are to superimpose a flow–volume loop of a tidal breath within a maximum flow–volume curve, or to use negative expiratory pressure technique. Likely this method is more accurate and can be used during spontaneous breathing. A definitive definition of dynamic hyperinflation is lacking in the literature, but serial measurements of inspiratory capacity during exercise will document the trend of end-expiratory lung volume and allow establishing relationships with other measurements such as dyspnea, respiratory pattern, exercise tolerance, and gas exchange.

Effects of Short-Acting Bronchodilators Added to Maintenance Tiotropium Therapy

BACKGROUND

Combining bronchodilators has been shown to be beneficial in patients with COPD. The additive effects of short-acting bronchodilators added to maintenance tiotropium therapy, however, are unknown.

METHODS

Following 3 weeks of tiotropium pretreatment, 60 patients with COPD (FEV1 40% of predicted) participated in a randomized, placebo-controlled study to assess add-on bronchodilator effects of ipratropium bromide (40 microg) or fenoterol (200 microg). Short-acting bronchodilators were added as a single dose 2 h and 8 h after tiotropium dosing. Serial lung function tests were performed over 9 h.

RESULTS

The peak FEV1 add-on response within 6 h with fenoterol was significantly greater than with placebo (137 mL) or ipratropium (84 mL); the response with ipratropium was slightly but significantly larger than with placebo (52 mL). One hour after the second dose of the test drugs, a similar order of treatment responses was found. The peak FVC add-on response was significant for fenoterol (249 mL) but not for ipratropium (42 mL).

CONCLUSIONS

In conclusion, both short-acting bronchodilator classes were effective when added to maintenance treatment with tiotropium. The addition of the beta2-adrenergic fenoterol provided greater additional bronchodilatation than the short-acting anticholinergic ipratropium. This is consistent with the expected effects of combining bronchodilators with different pharmacologic mechanisms. This randomized controlled trial was registered at www.clinicaltrials.gov (NCT00274066).

The Effects of Helium-Hyperoxia on 6-min Walking Distance in COPD

BACKGROUND

We hypothesized that breathing helium-hyperoxia (HeO2) would significantly improve 6-min walking test (6MWT) distance in COPD subjects.

METHODS

This was a blinded, randomized crossover study. At visit 1, we assessed pulmonary function, exercise capacity, and 6MWT distance. Visits 2 and 3 consisted of four 6MWTs in which the following different inspired gases were used: room air (RA) by mask; 100% O2 by mask (mask O2); 100% O2 by nasal prongs (nasal O2); and 70% He/30% O2 by mask (HeO2). Walking distance, shortness of breath, leg fatigue, O2 saturation, and heart rate (HR) were assessed.

RESULTS

Sixteen COPD subjects participated (mean FEV(1)/FVC ratio [+/- SD], 48 +/- 8%; mean FEV1, 55 +/- 13% predicted). Subjects walked farther when breathing HeO2 (564 m) compared to RA (497 m; p < 0.001), mask O2 (520 m; p < 0.001), or nasal O2 (528 m; p < 0.001). Despite the increased distance walked while breathing HeO2, there was no increase in shortness of breath or leg fatigue. There was desaturation when breathing RA (8%; p < 0.001) and nasal O2 (5%; p < 0.001), which was reduced when breathing HeO2 (3%; difference not significant) and mask O(2) (0%; difference not significant). There were no significant differences in HR in the four 6MWTs.

CONCLUSIONS

The use of HeO2 increased 6MWT distance in COPD subjects more than either mask O2 or nasal O2 compared to RA. The increased walking distance was not associated with increased shortness of breath or leg fatigue. The results suggest that clinical benefit would be obtained by administering HeO2 during exercise, which may have significant clinical implications for the management of COPD patients.

Oxygen therapy during exercise training in chronic obstructive pulmonary disease

BACKGROUND

Exercise training within the context of pulmonary rehabilitation improves outcomes of exercise capacity, dyspnea and health-related quality of life in individuals with chronic obstructive pulmonary disease (COPD). Supplemental oxygen in comparison to placebo increases exercise capacity in patients performing single-assessment exercise tests. The addition of supplemental oxygen during exercise training may enable individuals with COPD to tolerate higher levels of activity with less exertional symptoms, ultimately improving quality of life.

OBJECTIVES

To determine how supplemental oxygen in comparison to control (compressed air or room air) during the exercise-training component of a pulmonary rehabilitation program affects exercise capacity, dyspnea and health-related quality of life in individuals with COPD.

SEARCH STRATEGY

All records in the Cochrane Airways Group Specialized Register of trials coded as 'COPD' were searched using the following terms: (oxygen* or O2*) AND (exercis* or train* or rehabilitat* or fitness* or physical* or activ* or endur* or exert* or walk* or cycle*). Searching the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library), MEDLINE, EMBASE and CINAHL databases identified studies. The last search was carried out in June 2006.

SELECTION CRITERIA

Only randomized controlled trials (RCTs) comparing oxygen-supplemented exercise training to non-supplemented exercise training (control group) were considered for inclusion. Participants were 18 years or older, diagnosed with COPD and did not meet criteria for long-term oxygen therapy. No studies with mixed populations (pulmonary fibrosis, cystic fibrosis, etc) were included. Exercise training was greater than or equal to three weeks in duration and included a minimum of two sessions a week.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials for inclusion in the review and extracted data. Weighted mean differences (WMD) with 95% confidence intervals (CI) were calculated using a random-effects model. Missing data were requested from authors of primary studies.

MAIN RESULTS

Five RCTs met the inclusion criteria. The maximum number of studies compared in the meta-analysis was three (31 on oxygen versus 32 control participants), because all included studies did not measure the same outcomes. When two studies were pooled, statistically significant improvements of oxygen-supplemented exercise training were found in constant power exercise time, WMD 2.68 minutes (95% CI 0.07 to 5.28 minutes). Supplemental oxygen increased the average exercise time from 6 to 14 minutes; the control intervention increased average exercise time from 6 to 12 minutes. Constant power exercise end-of-test Borg score (on a scale from 1 to 10) also showed statistically significant improvements with oxygen-supplemented exercise training, WMD -1.22 units (95% CI -2.39 to -0.06). One study showed a significant improvement in the change of Borg score after the shuttle walk test, by -1.46 units (95% CI -2.72 to -0.19). There were no significant differences in maximal exercise outcomes, functional exercise outcomes (six-minute walk test), shuttle walk distance, health-related quality of life or oxygenation status. According to the GRADE system most outcomes were rated as low quality because they were limited by study quality.

AUTHORS' CONCLUSIONS

This review provides little support for oxygen supplementation during exercise training for individuals with COPD, but the evidence is very limited. Studies with larger number of participants and strong design are required to permit strong conclusions, especially for functional outcomes such as symptom alleviation, health-related quality of life and ambulation.

Effect of Albuterol on Maximal Exercise Capacity in Cystic Fibrosis

BACKGROUND

Inhaled, short-acting beta-adrenergic agonists (SAbetaAs) are widely prescribed in cystic fibrosis (CF) subjects, despite a lack of convincing data for efficacy and the potential for these agents to result in airway instability. We tested the hypothesis that inhaled albuterol would improve maximal exercise performance in CF subjects with airflow obstruction, as a result of acute bronchodilation.

METHODS

Randomized, double-blind, placebo-controlled crossover study of the effect of inhaled albuterol on maximal exercise performance in 20 stable adult CF patients (mean +/- SD age, 23.3 +/- 6.1 years; FEV(1), 57.65 +/- 17.13% of predicted).

RESULTS

Ventilatory limitation to exercise was demonstrated in 16 subjects (80%). Significant bronchodilation occurred with exercise alone (end-exercise FEV(1), 2.24 +/- 0.8 L; vs preexercise FEV(1), 2.09 +/- 0.77 L; p < 0.0001), but albuterol resulted in significantly greater exercise-induced bronchodilation than placebo (change in FEV(1), 0.3 +/- 0.15 L vs 0.15 +/- 0.11 L; 95% confidence interval [CI], + 0.07 to + 0.23; p < 0.001). However, there was no difference in maximal workload achieved (albuterol, 158 +/- 46 W; vs placebo, 158 +/- 45 W; 95% CI, - 4.41 to + 4.71; p = 0.95), nor any other measure of exercise performance including maximal oxygen uptake.

CONCLUSIONS

Despite causing significant acute bronchodilation, inhaled albuterol did not improve maximal exercise performance in ventilatory-limited CF adults, adding to the body of literature that fails to show any clinical benefit of SAbetaAs in CF subjects. The current results provide further evidence to question the widespread use of these agents, although the potential for adrenergic beta-agonists to instead improve submaximal exercise performance merits further investigation.

Advances in the management of chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD), the fourth leading cause of death, seems to be increasing in worldwide prevalence, and carries with it a significant health and economic burden. Smoking cessation is the only available intervention proven to halt disease progression. The authors discuss the role of the newly approved agent, varenicline, in promotion of smoking cessation. The remainder of presently available therapies treat the symptoms of COPD, but do not impact progression of disease. As the understanding of the pathogenesis of COPD improves, new targets for therapies are emerging. Given the large number of potential targets and the results of recent studies, it seems unlikely that a single new agent will result in a cure. Rather, management of COPD should involve a multi-pronged approach including smoking cessation, bronchodilators, treatment of infection, and eventual targeting of inflammatory pathways and genetic predispositions. In this article, the authors discuss presently available therapies as well as agents under development.

Single Dose of Tiotropium Improves the 6-Minute Walk Distance in Chronic Obstructive Pulmonary Disease

The aim of this study was to evaluate the effect of a single dose of tiotropium on the exercise capacity of stable chronic obstructive pulmonary disease (COPD) patients. The study was a randomized, placebo-controlled, double-blind, cross-over study. Forty-four stable COPD patients with moderate to severe airway obstruction were selected according to the GOLD criteria. The regular anticholinergic therapies of the patients were interrupted one week before the test. In the morning hours of the first day, half the group was given one capsule (18 mcg) of tiotropium and the other half was given placebo as inhalation using the HandiHaler device. Before and 120 min after the medication, the 6-min walk test was performed. Oxygen saturation, modified Borg dyspnea ratings, blood pressure, and heart rate were recorded before and after the test. The same procedure was repeated at the same time on the third day but this time the patients were given placebo if they used tiotropium on the first day and vice versa. Before using tiotropium or placebo there was no difference between 6-min walk distances. The 6-min walk distance after the use of tiotropium (429.3 +/- 70.6 m) was significantly longer than that after the use of placebo (414.7 +/- 74.6 m). The changes in Borg dyspnea ratings and arterial oxygen saturation values with tiotropium and placebo use were not significant. We conclude that exercise capacity might be improved by using a single-dose tiotropium inhalation in moderate to severe COPD patients.

Improvements in symptom-limited exercise performance over 8 h with once-daily tiotropium in patients with COPD

STUDY OBJECTIVES

We have previously shown that tiotropium at 18 mug reduces lung hyperinflation and dyspnea during exercise and improves exercise tolerance in patients with COPD. The present study was designed to gain further insight into the duration of improvements.

DESIGN, PATIENTS, AND INTERVENTIONS

A randomized, double-blind, placebo-controlled, parallel-group study was conducted in 261 COPD patients (mean age, 62.5 +/- 7.4 years [+/- SD]; 189 men and 72 women; mean FEV1, 1.2 +/- 0.4 L [43 +/- 12.7% predicted]). On day 0 (first dose), day 21, and day 42 of treatment, pulmonary function tests were performed before and 1 h 20 min after dosing, followed by a constant work rate cycle ergometry test (75% maximum work capacity) to symptom limitation at 2.25 h after dosing. On day 42, an additional constant work rate cycle ergometry test was performed at 8 h after dosing.

RESULTS

Adjusted mean (+/- SE) endurance time (ET) on day 42 was 803 +/- 40 s (tiotropium), vs 568 +/- 42 s (placebo) at 2.25 h after dosing (primary end point; treatment difference, 236 +/- 58 s; p = 0.0001) and 665 +/- 40 s (tiotropium) vs 494 +/- 42 s (placebo) at 8 h after dosing (treatment difference, 171 +/- 58 s; p = 0.0035). Adjusted mean dyspnea intensity at isotime on day 42 was 4.60 +/- 0.16 Borg units (tiotropium), vs 5.65 +/- 0.16 Borg units (placebo) at 2.25 h after dosing (p < 0.001), and 5.54 +/- 0.17 Borg units (tiotropium) vs 6.51 +/- 0.18 Borg units (placebo) at 8 h after dosing (p < 0.001). Adjusted mean pre-exercise inspiratory capacity (IC) on day 42 was 2.41 +/- 0.03 L (tiotropium) vs 2.19 +/- 0.03 L (placebo) at 2.25 h after dosing (p < 0.001), and 2.31 +/- 0.03 L (tiotropium) vs 2.16 +/- 0.03 L (placebo) at 8 h after dosing (p < 0.001). The significant increase in IC with tiotropium compared with placebo was maintained throughout exercise.

CONCLUSIONS

The present study confirms that tiotropium reduces lung hyperinflation at rest and during exercise, reduces exertional dyspnea, and improves symptom-limited exercise tolerance in COPD patients. Furthermore, this study shows that this improvement is present at 2.25 h and at 8 h after dosing after 6 weeks of treatment.

Alternative strategies for exercise critical power estimation in patients with COPD

Exercise critical power (CP) has been shown to represent the highest sustainable work rate (WR) in patients with chronic obstructive pulmonary disease (COPD). Parameter estimation, however, depends on 4 high-intensity tests performed, on different days, to the limit of tolerance (T(lim)). In order to establish a milder protocol that would be more suitable for disabled patients, we contrasted CP derived from 4, 3 and 2 tests (CP4, CP3 and CP2) in 8 males with moderate COPD. In addition, CP was calculated from 2 single-day tests performed on an inverse sequence (CP(2AB) and CP(2BA)): CP values within 5 W from CP4 were assumed as "clinically-acceptable" estimates. We found that [CP4-CP3] and [CP4-CP2] differences were within 5 W in 8 and 6 patients, respectively (95% confidence interval of the differences = -1.3 to 3.5 W and -11.5 to 6.5 W). There was a systematic decline on T(lim) when an exercise bout was performed after a previous test on the same day (P<0.05). Consequently, substantial differences were found between CP4 and any of the CP estimates obtained from single-day tests. In conclusion, clinically-acceptable estimates of CP can be obtained by using 3 or, in most circumstances, 2 constant WR tests in patients with moderate COPD--provided that they are not performed on the same day.

Effect of salbutamol on lung function and chest wall volumes at rest and during exercise in COPD

BACKGROUND

Inhaled bronchodilators can increase exercise capacity in chronic obstructive pulmonary disease (COPD) by reducing dynamic hyperinflation, but treatment is not always effective. This may reflect the degree to which the abdomen allows dynamic hyperinflation to occur.

METHOD

A double blind, randomised, crossover trial of the effect of 5 mg nebulised salbutamol or saline on endurance exercise time was conducted in 18 patients with COPD of mean (SD) age 67.1 (6.3) years and mean (SD) forced expiratory volume in 1 second (FEV1) of 40.6 (15.0)% predicted. Breathing pattern, metabolic variables, dyspnoea intensity, and total and regional chest wall volumes were measured non-invasively by optoelectronic plethysmography (OEP) at rest and during exercise.

RESULTS

Salbutamol increased FEV1, forced vital capacity (FVC) and inspiratory capacity and reduced functional residual capacity (FRC) and residual volume significantly. OEP showed the change in resting FRC to be mainly in the abdominal compartment. Although the mean (SE) end expiratory chest wall volume was 541 (118) ml lower (p<0.001) at the end of exercise, the endurance time was unchanged by the bronchodilator. Changes in resting lung volumes were smaller when exercise duration did not improve, but FEV1 still rose significantly after active drug. After the bronchodilator these patients tried to reduce the end expiratory lung volume when exercising, while those exercising longer continued to allow end expiratory abdominal wall volume to rise. The change to a more euvolumic breathing pattern was associated with a lower oxygen pulse and a significant fall in endurance time with higher isotime levels of dyspnoea.

CONCLUSIONS

Nebulised salbutamol improved forced expiratory flow in most patients with COPD, but less hyper-nflated patients tried to reduce the abdominal compartmental volume after active treatment and this reduced their exercise capacity. Identifying these patients has important therapeutic implications, as does an understanding of the mechanisms that control chest wall muscle recruitment.

Improvement in Exercise Tolerance With the Combination of Tiotropium and Pulmonary Rehabilitation in Patients With COPD

STUDY OBJECTIVES

Pulmonary rehabilitation (PR) improves exercise tolerance in COPD patients. Tiotropium is a once-daily, inhaled anticholinergic bronchodilator that provides sustained 24-h improvements in airflow and lung hyperinflation reduction. We hypothesized that ventilatory mechanics improvements from tiotropium would permit enhanced ability to train muscles of ambulation and therefore augment exercise tolerance benefits of PR.

DESIGN

In a randomized, double-blind, placebo-controlled trial (tiotropium, n = 47; placebo, n = 44), tiotropium (18 microg qd) was administered to COPD patients participating in 8 weeks of PR (treadmill training three times a week; >/= 30 min per session) at 17 sites. Study drug was administered 5 weeks prior to, 8 weeks during, and 12 weeks following PR. The primary end point was treadmill walking (0% incline) endurance time at 80% of maximum speed attained in an initial incremental test. The transition dyspnea index (TDI), St. George's respiratory questionnaire (SGRQ), and rescue albuterol use were secondary end points.

PARTICIPANTS

Mean age of the 93 participants was 67 years, 57% were men, and mean FEV(1) was 0.88 L (34% predicted).

RESULTS

Mean endurance time differences (tiotropium minus placebo) prior to PR, at the end of PR, and 12 weeks after PR were 1.65 min (p = 0.183), 5.35 min (p = 0.025), and 6.60 min (p = 0.018), respectively. Mean TDI focal scores at the end of PR were 1.75 for tiotropium and 0.91 for placebo (p > 0.05). At 12 weeks after PR, TDI focal scores were 1.75 for tiotropium and 0.08 for placebo (p < 0.05). Relative to placebo, tiotropium improved SGRQ total scores by 3.86 at the end of PR and 4.44 at 12 weeks after PR (p > 0.05). Mean albuterol use declined following PR plus tiotropium, compared to PR alone (p </= 0.05 for 17 of 25 weeks).

CONCLUSIONS

Tiotropium in combination with PR improved endurance of a constant work rate treadmill task and produced clinically meaningful improvements in dyspnea and health status compared to PR alone. Improvements with tiotropium were sustained for 3 months following PR completion.

Physiological effects of meals in difficult-to-wean tracheostomised patients with chronic obstructive pulmonary disease

OBJECTIVES

To evaluate effects of meals in difficult-to-wean tracheostomised patients with chronic obstructive pulmonary diseases during spontaneous breathing or Inspiratory Pressure Support.

DESIGN

Prospective, crossover, randomised, and physiological study.

SETTING

Weaning centre.

PATIENTS

Sixteen COPD undergoing either decreasing levels of pressure support or increasing periods of spontaneous breathing.

MEASUREMENTS

Each patient underwent monitoring during a 30-min procedure, during and after meals either under pressure support or spontaneous breathing on two consecutive days. Inductance plethysmography was used to monitor respiratory rate and tidal volume. Tidal volume by a flow transducer, arterial oxygen saturation, pulse rate, end-tidal CO2(,) and dyspnoea by a visual analogue scale were also assessed.

RESULTS

ANOVA analysis showed a significant increase under spontaneous breathing for respiratory rate (P<0.001) and for end tidal CO(2) (P<0.03) induced by the meals. Inspiratory pressure support was associated to significantly greater tidal volume (P<0.001), lower respiratory rate (P<0.032), lower respiratory rate/tidal volume (P<0.001), and lower pulse rate (P<0.047) than spontaneous breathing. Under spontaneous breathing but not under pressure support a statistically worsening in meal-induced dispnoea (P<0.001) was found.

CONCLUSIONS

In tracheostomised difficult-to-wean COPD patients: 1) under unassisted breathing, meals may induce an increase in respiratory rate, end-tidal CO(2), and dyspnoea; 2) inspiratory pressure support ventilation prevents dyspnoea from worsening during meals.

Chronic obstructive pulmonary disease: is there a case for early intervention?

Chronic obstructive pulmonary disease (COPD) is a highly prevalent condition that represents a significant economic burden to society. Early diagnosis of COPD offers the best opportunity to slow the progression of the disease through smoking cessation. Aggressive medical management of COPD for patients diagnosed at a moderate or severe stage is likely to be attractive from an economic standpoint, although prospective studies are needed to validate current evidence. Poor adherence to smoking cessation and pharmacologic therapy suggests that patient education is critical to successful intervention at all stages of illness. The economic value of aggressive pharmacotherapy for early-stage COPD is less certain, but the burden of illness and potential pharmacoeconomic benefits in such patients is a strong rationale for combined clinical and economic trials.

Clinically meaningful outcomes in patients with chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is characterized by chronic airflow limitation, gas exchange abnormalities, hyperinflation, and other pathophysiologic events. However, patients are usually unaware of these physical changes and only seek medical attention when distressing symptoms, such as dyspnea and exercise limitation, begin to appear. Therefore, it is reasonable to directly assess these clinical areas of importance to the patient, both as determinants of the impact of the disease process and as outcomes following intervention. Although many of the physiologic abnormalities of COPD are only partially or poorly reversible with treatment, dyspnea, exercise performance, and health status often show impressive gains with therapy. Incorporating clinically relevant outcome assessments complements traditional physiologic measurements and provides the clinician with a yardstick to determine whether a particular intervention is causing a meaningful improvement in the patient. This article discusses these clinical assessments and provides specific examples of their applicability and usefulness in treating patients with COPD.

Long-term pharmacologic management of patients with chronic obstructive pulmonary disease

Various pharmacologic agents are available for the long-term maintenance management of chronic obstructive pulmonary disease (COPD). The efficacy of these agents is based on their ability to decrease COPD symptoms, improve pulmonary function and quality of life, and reduce the frequency of acute exacerbations. Bronchodilators form the foundation of COPD therapy. Anticholinergic bronchodilators, such as ipratropium bromide and especially tiotropium, are first-line anticholinergic agents that can be used alone or in combination with long-acting or short-acting beta2-agonists to achieve these primary goals of COPD treatment. Methylxanthines are useful primarily for their nonbronchodilatory (ie, positive) effects on pulmonary arterial pressure, pulmonary vascular resistance, renal blood flow, and glomerular filtration rate. Inhaled corticosteroids are reserved only for the few patients with severe disease who experience symptoms and acute exacerbations despite optimized multiple bronchodilator therapy. This article reviews agents that are currently available and those that are in development for the long-term management of COPD, with special emphasis on the anticholinergic bronchodilators.

New therapies for chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is the most common lung disease, carrying a significant mortality and morbidity. None of the therapeutic interventions currently available alter the progression of the disease. As our understanding of the basic mechanisms of alveolar destruction and airflow limitation improves, new targets are identified that may eventually result in treatment options which will affect the progression of this disease. In this review, we discuss some of the novel therapeutic options recently developed that may have an impact on the management of COPD. Future directions in research and development of pharmacological agents based on improved understanding of COPD are also discussed.

Therapy for chronic obstructive pulmonary disease in the 21st century

Chronic obstructive pulmonary disease (COPD) is a common, smoking-related, severe respiratory condition characterised by progressive, irreversible airflow limitation. Current treatment of COPD is symptomatic, with no drugs capable of halting the relentless progression of airflow obstruction. Better understanding of the airway inflammation, oxidative stress and alveolar destruction that characterise COPD has delineated new disease targets, with consequent identification of novel compounds with therapeutic potential. These new drugs include aids to smoking cessation (e.g. bupropion) and improvements to existing therapies, for example long-acting rather than short-acting bronchodilators, as well as combination therapy. New antiproteases include acyl-enzyme and transition state inhibitors of neutrophil elastase (e.g. sivelestat and ONO-6818), matrix metalloprotease inhibitors (e.g. batimastat), cathepsin inhibitors and peptide protease inhibitors (e.g. DX-890 [EPI-HNE-4] and trappin-2). New antioxidants include superoxide dismutase mimetics (e.g. AEOL-10113) and spin trap compounds (e.g. N-tert-butyl-alpha-phenylnitrone). New anti-inflammatory interventions include phosphodiesterase-4 inhibitors (e.g. cilomilast), inhibitors of tumour necrosis factor-alpha (e.g. humanised monoclonal antibodies), adenosine A(2a) receptor agonists (e.g. CGS-21680), adhesion molecule inhibitors (e.g. bimosiamose [TBC1269]), inhibitors of nuclear factor-kappaB (e.g. the naturally occurring compounds hypoestoxide and (-)-epigallocatechin-3-gallate) and activators of histone deacetylase (e.g. theophylline). There are also selective inhibitors of specific extracellular mediators such as chemokines (e.g. CXCR2 and CCR2 antagonists) and leukotriene B(4) (e.g. SB201146), and of intracellular signal transduction molecules such as p38 mitogen activated protein kinase (e.g. RWJ67657) and phosphoinositide 3-kinase. Retinoids may be one of the few potential treatments capable of reversing alveolar destruction in COPD, and a number of compounds are in clinical trial (e.g. all-trans-retinoic acid). Talniflumate (MSI-1995), an inhibitor of human calcium-activated chloride channels, has been developed to treat mucous hypersecretion. In addition, the purinoceptor P2Y(2) receptor agonist diquafosol (INS365) is undergoing clinical trials to increase mucus clearance. The challenge to transferral of these new compounds from preclinical research to disease management is the design of effective clinical trials. The current scarcity of well characterised surrogate markers predicts that long-term studies in large numbers of patients will be needed to monitor changes in disease progression.

Effects of inhaled furosemide on exertional dyspnea in chronic obstructive pulmonary disease

The aim of this study is to investigate the effects of inhaled furosemide on the sensation of dyspnea produced during exercise in patients with stable chronic obstructive pulmonary disease (COPD). In a double-blind, randomized, crossover study we compared the effect of inhaled furosemide on dyspneic sensation during exercise testing with that of placebo. Spirometry and incremental and constant-load exercise testing were performed after inhalation of placebo or furosemide on 2 separate days in 19 patients with moderate or severe COPD. Subjects were asked to rate their sensation of respiratory discomfort using a 100-mm visual analog scale. There was significant improvement in mean FEV1 and FVC after inhalation of furosemide (p = 0.038 and 0.005, respectively) but not after placebo. At standardized exercise time during constant-load exercise testing but not during incremental exercise, the mean dyspneic visual analog scale score was lower after inhalation of furosemide compared with placebo (33.7 +/- 25.2 vs. 42.4 +/- 24.0 mm, respectively, p = 0.014). We conclude that inhalation of furosemide alleviates the sensation of dyspnea induced by constant-load exercise testing in patients with COPD and that there is significant bronchodilation after inhalation of furosemide compared with placebo in these patients.

[Bronchodilators in COPD: latest recommendations, recent data and perspectives]

DEMONSTRATED EFFICACY: Inhaled bronchodilators improve the quality of life of COPD patients by reducing dyspnea and exacerbation frequency. There is no data supporting the superiority of one of the families of inhaled bronchodilators (i.e. beta 2 agonists and anticholinergic agents) over the other. Thus, the choice has to be based on the individual symptomatic response. These agents can be combined. OTHER POSSIBILITIES: Long-acting beta 2 agonists are already available and long-acting anticholinergics should be marketed soon. Theophylline has a lower efficacy/tolerance ratio than inhaled bronchodilators but can provide additional benefits when associated with the latter in some patients. Phosphodiesterase inhibitors with both bronchodilating and anti-inflammatory effect are being developed. THE BENEFITS OF CORTICOSTEROIDS: Finally, in symptomatic patients with FEV1<50% predicted and repeated exacerbations despite bronchodilators, inhaled corticosteroids can be added.