Chronic obstructive pulmonary disease (COPD) is a complex condition with pulmonary and extra-pulmonary manifestations. This study describes the heterogeneity of COPD in a large and well characterised and controlled COPD cohort (ECLIPSE). We studied 2164 clinically stable COPD patients, 337 smokers with normal lung function and 245 never smokers. In these individuals, we measured clinical parameters, nutritional status, spirometry, exercise tolerance, and amount of emphysema by computed tomography. COPD patients were slightly older than controls and had more pack years of smoking than smokers with normal lung function. Co-morbidities were more prevalent in COPD patients than in controls, and occurred to the same extent irrespective of the GOLD stage. The severity of airflow limitation in COPD patients was poorly related to the degree of breathlessness, health status, presence of co-morbidity, exercise capacity and number of exacerbations reported in the year before the study. The distribution of these variables within each GOLD stage was wide. Even in subjects with severe airflow obstruction, a substantial proportion did not report symptoms, exacerbations or exercise limitation. The amount of emphysema increased with GOLD severity. The prevalence of bronchiectasis was low (4%) but also increased with GOLD stage. Some gender differences were also identified. The clinical manifestations of COPD are highly variable and the degree of airflow limitation does not capture the heterogeneity of the disease.

To date, no international surveys estimating the burden of chronic obstructive pulmonary disease (COPD) in the general population have been published. The Confronting COPD International Survey aimed to quantify morbidity and burden in COPD subjects in 2000.From a total of 201,921 households screened by random-digit dialling in the USA, Canada, France, Italy, Germany, the Netherlands, Spain and the UK, 3,265 subjects with a diagnosis of COPD, chronic bronchitis or emphysema, or with symptoms of chronic bronchitis, were identified.The mean age of the subjects was 63.3 yrs and 44.2% were female. Subjects with COPD in North America and Europe appear to underestimate their morbidity, as shown by the high proportion of subjects with limitations to their basic daily life activities, frequent work loss (45.3% of COPD subjects of <65 yrs reported work loss in the past year) and frequent use of health services (13.8% of subjects required emergency care in the last year), and may be undertreated. There was a significant disparity between subjects' perception of disease severity and the degree of severity indicated by an objective breathlessness scale. Of those with the most severe breathlessness (too breathless to leave the house), 35.8% described their condition as mild or moderate, as did 60.3% of those with the next most severe degree of breathlessness (breathless after walking a few minutes on level ground).This international survey confirmed the great burden to society and high individual morbidity associated with chronic obstructive pulmonary disease in subjects in North America and Europe.

Rationale: Chronic obstructive pulmonary disease (COPD) is a progressive, smoking-related, inflammatory lung disease in which tumor necrosis factor-α is overexpressed and has been suggested to play a pathogenic role. Objectives: To determine if infliximab, an anti–TNF-α antibody, results in clinical benefit and has an acceptable safety profile in patients with moderate to severe COPD. Methods: In a multicenter, randomized, double-blind, placebo-controlled, parallel-group, dose-finding study, subjects with moderate to severe COPD received infliximab (3 mg/kg [n = 78] or 5 mg/kg [n = 79]) or placebo (n = 77) at Weeks 0, 2, 6, 12, 18, and 24. Efficacy, health status, and safety were assessed through Week 44. Measurements and Main Results: Infliximab was generally well tolerated, but showed no treatment benefit as measured by the primary endpoint, Chronic Respiratory Questionnaire total score. Similarly, there was no change in secondary measures, including prebronchodilator FEV₁, 6-min walk distance, SF-36 physical score, transition dyspnea index, or moderate-to-severe COPD exacerbations. Post hoc analysis revealed that subjects who were younger or cachectic showed improvement in the 6-min walk distance. Malignancies were diagnosed during the study in 9 of 157 infliximab-treated subjects versus 1 of 77 placebo-treated subjects. No opportunistic infections were observed, and there were no differences in the occurrence of antibiotic-requiring infections, although the incidence of pneumonia was higher in infliximab-treated subjects. No infection-related mortality was observed. Higher proportions of infliximab-treated subjects discontinued the study agent due to adverse events (20–27%) than did placebo-treated subjects (9%). Conclusions: Subjects with moderate to severe COPD did not benefit from treatment with infliximab. Although not statistically significant, more cases of cancer and pneumonia were observed in the infliximab-treated subjects. The impact of infliximab on malignancy risk in patients with COPD needs to be further elucidated.

As chronic obstructive pulmonary disease (COPD) is a heterogeneous disease it is unlikely that all patients will benefit equally from a given therapy. Roflumilast, an oral, once-daily phosphodiesterase 4 inhibitor, has been shown to improve lung function in moderate and severe COPD but its effect on exacerbations in unselected populations was inconclusive. This led to the question of whether a responsive subset existed that could be investigated further.

Matrix metalloproteinase-9 (MMP-9) is a matrix-degrading enzyme implicated in many biological processes, including inflammation. It is produced by many cells, including fibroblasts. When cultured in three-dimensional (3D) collagen gels, fibroblasts contract the surrounding matrix, a function that is thought to model the contraction that characterizes both normal wound repair and fibrosis. The current study was designed to evaluate the role of endogenously produced MMP-9 in fibroblast contraction of 3D collagen gels. Fibroblasts from mice lacking expression of MMP-9 and human lung fibroblasts (HFL-1) transfected with MMP-9 small-interfering RNA (siRNA) were used. Fibroblasts were cast into type I collagen gels and floated in culture medium with or without transforming growth factor (TGF)-β1 for 5 days. Gel size was determined daily using an image analysis system. Gels made from MMP-9 siRNA-treated human fibroblasts contracted less than control fibroblasts, as did fibroblasts incubated with a nonspecific MMP inhibitor. Similarly, fibroblasts cultured from MMP-9-deficient mice contracted gels less than did fibroblasts from control mice. Transfection of the MMP-9-deficient murine fibroblasts with a vector expressing murine MMP-9 restored contractile activity to MMP-9-deficient fibroblasts. Inhibition of MMP-9 reduced active TGF-β1 and reduced several TGF-β1-driven responses, including activity of a Smad3 reporter gene and production of fibronectin. Because TGF-β1 also drives fibroblast gel contraction, this suggests the mechanism for MMP-9 regulation of contraction is through the generation of active TGF-β1. This study provides direct evidence that endogenously produced MMP-9 has a role in regulation of tissue contraction of 3D collagen gels mediated by fibroblasts.