Effect of bronchodilation on expiratory flow limitation and resting lung mechanics in COPD.

ABSTRACT: Bronchodilator drugs produce variable improvements in forced expiratory volume in 1 s (FEV1), but larger changes in end-expiratory lung volume (EELV) in chronic obstructive pulmonary disease (COPD), which were suggested to be related to the presence of expiratory flow limitation (EFL) at rest. We tested this concept in 42 COPD patients (FEV1 42.3¡13.8% predicted) during spontaneous breathing before and after 5 mg nebulised salbutamol. EFL was detected by within-breath changes in respiratory system reactance measured by a multifrequency forced oscillation method, while changes in EELV were assessed by inspiratory capacity (IC). Bronchodilation (BD) increased IC (from 1.8¡0.5 to 2.1¡0.6 L, p,0.001) and reduced inspiration resistance (R – insp) at 5 Hz (from 5.1¡1.6 to 4.2¡1.5 cmH2O?s?L-1, p,0.001). R – insp identified BD responders with a discriminative power of 80.1%. In total, 20 patients were flow-limited before BD. They showed worse spirometry and higher residual volume, but significant improvements in IC were seen in all patients irrespective of flow limitation. Changes inR – insp were confined to flow-limited patients, as were reactance changes. BD reduced the degree of heterogeneity in the respiratory system, a change best seen with inspiratory values. BD has complex effects on lung mechanics in COPD, and EFL affects both this and the response of some respiratory variables to treatment. However, changes in EELV are consistently seen, irrespective of the presence of flow limitation at rest

Respiratory system impedance with impulse oscillometry in healthy and COPD subjects: ECLIPSE baseline results

SummaryRationaleCurrent assessment of COPD relies extensively on the use of spirometry, an effort-dependent maneuver. Impulse oscillometry (IOS) is a non-volitional way to measure respiratory system mechanics, but its relationship to structural and functional measurements in large groups of patients with COPD is not clear.ObjectivesWe evaluated the ability of IOS to detect and stage COPD severity in the prospective ECLIPSE cohort of COPD patients defined spirometrically, and contrasted with smoking and non-smoking healthy subjects. Additionally, we assessed whether IOS relates to extent of CT-defined emphysema.MethodsWe measured lung impedance with IOS in healthy non-smokers (n = 233), healthy former smokers (n = 322) or patients with COPD (n = 2054) and related these parameters with spirometry and areas of low attenuation in lung CT.Measurements and main resultsIn healthy control subjects, IOS demonstrated good repeatability over 3 months. In the COPD group, respiratory system impedance was worse compared with controls as was frequency dependence of resistance, which related to GOLD stage. However, 29–86% of the COPD subjects had values that fell within the 90% confidence interval of several parameters of the healthy non-smokers. Although mean values for impedance parameters and CT indices worsened as GOLD severity increased, actual correlations between them were poor (r ≤ 0.16).ConclusionsIOS can be reliably used in large cohorts of subjects to assess respiratory system impedance. Cross-sectional data suggest that it may have limited usefulness in evaluating the degree of pathologic disease, whereas its role in assessing disease progression in COPD currently remains undefined

Beclomethasone/formoterol in the management of COPD: a randomised controlled trial.

To evaluate the effect of beclomethasone/formoterol versus budesonide/formoterol (non-inferiority) and versus formoterol (superiority) in patients with severe stable chronic obstructive pulmonary disease (COPD). METHODS: A double-blind, double-dummy, randomised, active-controlled, parallel-group study. After 4 weeks run-in with ipratropium/salbutamol (40/200 μg, three times daily) patients were randomised to receive beclomethasone/formoterol (200/12 μg pressurised metered dose inhaler), budesonide/formoterol (400/12 μg dry powder inhaler) or formoterol (12 μg dry powder inhaler) twice daily for 48 weeks. Co-primary efficacy variables were change from baseline to 48 weeks in pre-dose morning forced expiratory volume in 1 s (FEV(1)) and mean rate of COPD exacerbations. RESULTS: Of 718 patients randomised, 703 (232 beclomethasone/formoterol, 238 budesonide/formoterol, 233 formoterol) were in the ITT analysis. Improvement in pre-dose morning FEV(1) was 0.077 L, 0.080 L and 0.026 L for beclomethasone/formoterol, budesonide/formoterol and formoterol respectively (LS mean from the ANCOVA model). Beclomethasone/formoterol was not inferior to budesonide/formoterol (95% CI of the difference -0.052, 0.048) and superior to formoterol (p = 0.046). The overall rate of COPD exacerbations/patient/year was similar and not statistically significantly different among treatments (beclomethasone/formoterol 0.414, budesonide/formoterol 0.423 and formoterol 0.431). Quality of life and COPD symptoms improved in all groups and use of rescue medication decreased. Safety profiles were as expected and treatments well-tolerated. CONCLUSIONS: Beclomethasone/formoterol (400/24 μg) treatment for 48 weeks improved pulmonary function, reduced symptoms compared to formoterol, was safe and well-tolerated in patients with severe stable COPD. Neither of the long-acting β2-agonist/inhaled corticosteroid combinations affected the low exacerbation rate seen in this population

Physical activity monitoring in COPD: Compliance and associations with clinical characteristics in a multicenter study

SummaryBackgroundLittle is known about COPD patients’ compliance with physical activity monitoring and how activity relates to disease characteristics in a multi-center setting.MethodsIn a prospective study at three Northern European sites physical activity and clinical disease characteristics were measured in 134 COPD patients (GOLD-stage II–IV; BODE index 0–9) and 46 controls. Wearing time, steps per day, and the physical activity level (PAL) were measured by a multisensory armband over a period of 6 consecutive days (in total, 144h). A valid measurement period was defined as ≥22 h wearing time a day on at least 5 days.ResultsThe median wearing time was 142 h:17 min (99%), 141 h:1min (98%), and 142 h:24 min (99%), respectively in the three centres. A valid measurement period was reached in 94%, 97%, and 94% of the patients and did not differ across sites (P = 0.53). The amount of physical activity did not differ across sites (mean steps per day, 4725 ± 3212, P = 0.58; mean PAL, 1.45 ± 0.20, P = 0.48). Multivariate linear regression analyses revealed significant associations of FEV1, 6-min walk distance, quadriceps strength, fibrinogen, health status, and dyspnoea with both steps per day and PAL. Previously unrecognized correlates of activity were grade of fatigue, degree of emphysema, and exacerbation rate.ConclusionsThe excellent compliance with wearing a physical activity monitor irrespective of study site and consistent associations with relevant disease characteristics support the use of activity monitoring as a valid outcome in multi-center studies

Changes in body composition in patients with chronic obstructive pulmonary disease: do they influence patient-related outcomes?

Aims: The follow-up of the ECLIPSE study, a prospective longitudinal study to identify and define parameters that predict disease progression over 3 years in chronic obstructive pulmonary disease (COPD), allows the examination of the effect of body composition changes on COPD-related outcomes. Methods: Body composition and health status were established in 2,115 COPD patients, 327 smoking and 239 nonsmoking controls at baseline and 3 years, while mortality was recorded in year 2 and 3 in the COPD patients. Associations between fat free mass index (FFMI) and fat mass index (FMI) changes to deterioration in health status and mortality were determined. Results: Change in FFMI and FMI over 3 years was small and comparable between the groups. Underweight and obese patients had the worst health status. Worsening health status was associated with FFMI decrease in underweight patients and FMI increase in overweight/obese patients. While overweight patients had the lowest mortality, FFMI or FMI decrease was associated with a higher mortality. Conclusion: Changes in body composition over 3 years were small and comparable in COPD patients and control subjects. Nevertheless, muscle mass decline in underweight and fat mass increase in overweight/obese patients is associated with worsening health status. Overweight is associated with decreased mortality, but muscle mass and fat mass decline are detrimental for mortality. (c) 2013 S. Karger AG, Basel

Chronic Obstructive Pulmonary Disease Phenotypes: The Future of COPD.

Significant heterogeneity of clinical presentation and disease progression exists within COPD. While FEV1 inadequately describes this heterogeneity, a clear alternative has not emerged. The goal of phenotyping is to identify patient groups with unique prognostic or therapeutic characteristics, but significant variation and confusion surrounds use of the term "phenotype" in COPD. "Phenotype" classically refers to any observable characteristic of an organism, and up until now, multiple disease characteristics have been termed COPD "phenotypes." We, however, propose the following variation on this definition: "a single or combination of disease attributes that describe differences between individuals with COPD as they relate to clinically meaningful outcomes (symptoms, exacerbations, response to therapy, rate of disease progression or death)." This more focused definition allows for classification of patients into distinct prognostic and therapeutic subgroups for both clinical and research purposes. Ideally, individuals sharing a unique phenotype would also ultimately be determined to have a similar underlying biologic or physiologic mechanism(s) to guide the development of therapy where possible. It follows that any proposed phenotype whether defined by symptoms, radiography, physiology, cellular or molecular fingerprint will require an iterative, validation process in which "candidate" phenotypes are identified before their relevance to clinical outcome is determined. While this schema represents an ideal construct, we acknowledge any phenotype may be etiologically heterogeneous and that any one individual may manifest multiple phenotypes. We have much yet to learn, but establishing a common language for future research will facilitate our understanding and management of the complexity implicit to this disease