Ongoing airway inflammation in patients with COPD who do not currently smoke

The dynamics and associations of airway neutrophilia post lung transplantation

Bronchoalveolar lavage (BAL) neutrophilia has been repeatedly observed in lung transplant recipients with established bronchiolitis obliterans syndrome (BOS). Little is known of the fluctuations in BAL and airway neutrophilic inflammation post-transplant. This prospective longitudinal study aimed to evaluate the dynamic changes of lung allograft neutrophils with time, immunosuppression, infection and BOS. A total of 28, initially healthy, BOS 0, lung transplant recipients underwent 134 bronchoscopic assessments, including BAL and endobronchial biopsies (EBB) (with immunohistochemistry) over 3-year follow up. Subsequently, 21 developed BOS 0p and 16 ultimately BOS. Compared to controls, there was early and persistent BAL neutrophilia (p < 0.05), contrasting with an initially normal EBB that shows a progressive increased airway wall neutrophil infiltrate. BAL neutrophilia (but not airway wall neutrophilia) was most striking when there was concomitant bronchopulmonary infection, particularly in the patients with BOS. Univariate and multivariate analyses suggested that BAL neutrophilia was linked to markers of infection while EBB neutrophilia was linked with coexistent inflammation with macrophages and lymphocytes.

IN CONCLUSION

(i) BAL neutrophilia is predominantly associated with infection; (ii) Airway wall neutrophilia (as monitored by EBB) increases with time post-transplant and is not associated with infection; (iii) By itself, BOS is not the major contributor to BAL and EBB neutrophilia.

Airway inflammation and bronchial bacterial colonization in chronic obstructive pulmonary disease

RATIONALE

Inflammation is now recognized as an integral part of the pathogenesis of chronic obstructive pulmonary disease (COPD). In contrast to the sterile airways of normal lungs, bacterial pathogens are often isolated from the airways in stable COPD. This "colonization" of the tracheobronchial tree, currently believed to be innocuous, could serve as an inflammatory stimulus, independent of current tobacco smoke exposure.

OBJECTIVE

To test the hypothesis that bacterial colonization is associated with airway inflammation in stable COPD.

METHODS

Bronchoscopy with bronchoalveolar lavage (BAL) was performed in three groups of subjects: 26 ex-smokers with stable COPD (COPD), 20 ex-smokers without COPD (ex-smokers), and 15 healthy nonsmokers (nonsmokers). Quantitative bacterial cultures, cell counts, chemokine, cytokine, proteinase/antiproteinase, and endotoxin levels in the BAL fluid were compared.

RESULTS

Potentially pathogenic bacteria were recovered at > or = 100 cfu/ml in 34.6% of COPD, 0% of ex-smokers, and in 6.7% of nonsmokers (p = 0.003). All values are expressed as median (interquartile range). Subjects with colonized COPD had significantly greater relative (12.0 [28.4] vs. 3.0 [7.8]%, p = 0.03) and absolute (4.98 [5.26] x 10(4)/ml vs. 3.04 [2.82] x 10(4)/ml, p = 0.02) neutrophil counts, interleukin 8 (33.8 [189.8] vs. 16.9 [20.1] pg/ml, p = 0.005), active matrix metalloproteinase-9 (2.16 [4.30] vs. 0.84 [0.99] U/ml, p = 0.03), and endotoxin (36.0 [72.6] vs. 3.55 [7.17] mEU/ml, p = 0.004) levels in the BAL than the subjects with noncolonized COPD. These inflammatory constituents of BAL were also significantly elevated in subjects with colonized COPD when compared with ex-smokers and nonsmokers.

CONCLUSIONS

Bacterial colonization is associated with neutrophilic airway lumen inflammation in ex-smokers with COPD and could contribute to progression of airway disease in COPD.

Relation between duration of smoking cessation and bronchial inflammation in COPD

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is associated with airway inflammation. Although smoking cessation improves symptoms and the decline in lung function in COPD, it is unknown whether bronchial inflammation in patients with established COPD varies with the duration of smoking cessation.

METHODS

114 patients (99 men) with COPD of mean (SD) age 62 (8) years, a median (IQR) smoking history of 42 (31-55) pack years, no inhaled or oral corticosteroids, all current or ex-smokers (n = 42, quit >1 month, median cessation duration 3.5 years), post-bronchodilator FEV(1) 63 (9)% predicted, and FEV(1)/IVC 48 (9)% were studied cross sectionally. The numbers of subepithelial T lymphocytes (CD3, CD4, CD8), neutrophils, macrophages, eosinophils, mast cells, and plasma cells were measured in bronchial biopsy specimens (median (IQR)/0.1 mm(2)) using fully automated image analysis.

RESULTS

Ex-smokers with COPD had higher CD3+, CD4+, and plasma cell numbers than current smokers with COPD (149 (88-225) v 108 (61-164), p = 0.036; 58 (32-90) v 40 (25-66), p = 0.023; and 9.0 (5.5-20) v 7.5 (3.1-14), p = 0.044, respectively), but no difference in other inflammatory cells. Short term ex-smokers (<3.5 years) had higher CD4+ and CD8+ cell numbers than current smokers (p = 0.017, p = 0.023; respectively). Conversely, long term ex-smokers (quit > or =3.5 years) had lower CD8+ cell numbers than short term ex-smokers (p = 0.009), lower CD8/CD3 ratios than both current smokers and short-term ex-smokers (p = 0.012, p = 0.003; respectively), and higher plasma cell numbers than current smokers (p = 0.003).

CONCLUSIONS

With longer duration of smoking cessation, CD8 cell numbers decrease and plasma cell numbers increase. This indicates that bronchial T lymphocyte and plasma cell counts, but not other inflammatory cells, are related to duration of smoking cessation in patients with COPD.

Antiinflammatory effects of salmeterol/fluticasone propionate in chronic obstructive lung disease

RATIONALE

No currently available treatment is reported to reduce the exaggerated airway wall inflammation of chronic obstructive pulmonary disease.

OBJECTIVES

We tested the hypothesis that inhaled combined long-acting beta2-agonist (salmeterol) and corticosteroid (fluticasone propionate) will reduce inflammation.

METHODS

Bronchial biopsies and induced sputum were taken from 140 current and former smokers (mean age, 64 yr) with moderate to severe disease, randomized in a 13-wk double-blind study to placebo (n = 73) or salmeterol/fluticasone propionate 50/500 microg (n = 67) twice daily. Biopsies were repeated at 12 wk and sputa at 8 and 13 wk. After adjustment for multiplicity, comparisons between active and placebo were made for median change from baseline in the numbers of biopsy CD8+ and CD68+ cells/mm2 and sputum neutrophils.

MEASUREMENTS AND MAIN RESULTS

Combination therapy was associated with a reduction in biopsy CD8+ cells of -118 cells/mm2 (95% confidence interval [CI], -209 to -42; p = 0.02), a reduction of 36% over placebo (p = 0.001). CD68+ cells were unaffected by combination treatment. Sputum differential (but not total) neutrophils reduced progressively and, at Week 13, significantly with combination treatment (median treatment difference, 8.5%; 95% CI, 1.75%-15.25%; p = 0.04). The combination also significantly reduced biopsy CD45+ and CD4+ cells and cells expressing genes for tumor necrosis factor-alpha and IFN-gamma and sputum total eosinophils (all p < or = 0.03). These antiinflammatory effects were accompanied by a 173-ml (95% CI, 104-242; p < 0.001) improvement in prebronchodilator FEV1.

CONCLUSIONS

The combination of salmeterol and fluticasone propionate has a broad spectrum of antiinflammatory effects in both current and former smokers with chronic obstructive pulmonary disease, which may contribute to clinical efficacy.

A novel flow cytometric assay of human whole blood neutrophil and monocyte CD11b levels: upregulation by chemokines is related to receptor expression, comparison with neutrophil shape change, and effects of a chemokine receptor (CXCR2) antagonist

RATIONALE

Smokers who develop chronic obstructive pulmonary disease (COPD) have amplified inflammation within their lungs, involving selective tissue accumulation of neutrophils, macrophages and CD8+ T cells. CD11b (Mac-1, alphaMbeta(2)-integrin) is both a complement receptor (CR3) and a cell adhesion molecule present on the surface of peripheral blood leukocytes, and undergoes rapid surface upregulation from preformed cytoplasmic stores on activation. Cellular activation can also trigger chemotaxis and shape change, the activation itself being caused by the binding of chemokines to cell surface receptors.

METHODS

We developed a method of whole blood flow cytometry to measure neutrophil and monocyte CD11b upregulation on CD16+ and CD14+ cells, employing staining with the nuclear dye LDS-751 immediately before flow cytometry. In addition we assessed neutrophil shape change by modified gated autofluorescence with forward scatter (GAFS), this being correlated with chemotactic responses.

RESULTS

In smokers with COPD there was a lower maximal shape change for neutrophils in response to CXCL8 (IL-8) in comparison to healthy smokers (p=0.025), and a trend for lower expression of CD11b and shape change in response to CXCL1 (GRO-alpha). Neutrophils were found to predominantly express chemokine receptors CXCR1 and CXCR2 and respond to CXCL8 with CD11b upregulation, while monocytes express more CCR2 and upregulate CD11b preferentially to CCL2 (MCP-1). A CXCR2 antagonist (SB-656933) was found to inhibit neutrophil CD11b upregulation (IC50=260.7nM) and shape change (IC50=310.5nM) in COPD patients.

CONCLUSIONS

Neutrophils and monocytes participate in inflammatory processes in a range of diseases. These whole blood assays can be employed to monitor activity in disease and perform in vitro and ex vivo assessment of chemokine receptor (CXCR) antagonists.

Cigarette smoke-induced emphysema: A role for the B cell?

RATIONALE

Little is known about what drives the inflammatory reaction in the development of chronic obstructive lung disease. B cells have been found.

OBJECTIVE

To study the involvement of B cells in the development of emphysema.

METHODS

The presence of B-cell follicles and their interaction with other cells were investigated in lungs of patients with chronic obstructive pulmonary disease and of smoking mice. B cells were isolated from lymphoid follicles by laser microdissection and analyzed for the presence of immunoglobulin rearrangements and somatic mutations.

MAIN RESULTS

Lymphoid follicles consisting of B cells and follicular dendritic cells with adjacent T cells were demonstrated both in the parenchyma and in bronchial walls of patients with emphysema. A clonal process was observed in all follicles and the presence of ongoing somatic mutations was observed in 75% of the follicles, indicating oligoclonal, antigen-specific proliferation. Similar lymphoid follicles were detected in mice that had developed pulmonary inflammation and progressive alveolar airspace enlargement after smoking. The increase in the number of B-cell follicles was progressive with time and correlated with the increase in mean linear intercept. Specific bacterial or viral nucleic acids could not be detected.

CONCLUSIONS

B-cell follicles with an oligoclonal, antigen-specific reaction were found in men and mice with emphysema. In mice, the development was progressive with time and correlated with the increase in airspace enlargement. We hypothesize that these B cells contribute to the inflammatory process and/or the development and perpetuation of emphysema by producing antibodies against either tobacco smoke residues or extracellular matrix components.

Cilomilast for COPD

BACKGROUND

COPD is a relentless, progressive disease. This study evaluated the efficacy of cilomilast, a selective phosphodiesterase (PDE) 4 inhibitor, in the treatment of COPD.

METHODS

This was a randomized, double-blind, placebo-controlled, parallel-group, multicenter study in subjects with COPD. After a 4-week, single-blind, placebo run-in period, eligible subjects were randomized in a 2:1 ratio to receive oral cilomilast, 15 mg bid, or placebo for 24 weeks. Subjects between 40 and 80 years of age who had received a diagnosis of COPD were eligible for the study. The primary efficacy variables were changes from baseline in trough (ie, predose) FEV1 and in total score of the St. George's Respiratory Questionnaire (SGRQ). A key secondary end point was the incidence rate of COPD exacerbations.

RESULTS

The average change from baseline in FEV1 over 24 weeks in the cilomilast group was an increase of 10 mL compared with a decrease of 30 mL in the placebo group (difference, 40 mL; p = 0.002). When averaged over 24 weeks, there was a clinically significant reduction in the mean total SGRQ score in subjects receiving cilomilast therapy, with a difference of 4.1 U compared with subjects who received placebo (p = 0.001). A greater percentage of subjects in the cilomilast group were exacerbation-free at 24 weeks (74%; p = 0.008) compared with placebo (62%). Adverse events were generally mild or moderate and were not unexpected for this class of medications. GI adverse events that interfered with daily activities (cilomilast, 17%; placebo, 8%) predominantly occurred within the first 3 weeks of initiating cilomilast therapy.

CONCLUSION

Cilomilast is an orally active, potent, and selective inhibitor of PDE-4. Cilomilast maintained pulmonary function and improved health status, and reduced the rate of COPD exacerbations during 24 weeks of treatment. This study supports the use of cilomilast, a novel, selective PDE-4 inhibitor, in subjects with COPD.

First Study of Infliximab Treatment in Patients with Chronic Obstructive Pulmonary Disease

RATIONALE

Tumor necrosis factor-alpha is believed to be important in the induction and maintenance of airway inflammation in chronic obstructive pulmonary disease.

OBJECTIVES

We aimed to evaluate the effect of the anti-tumor necrosis factor-alpha drug infliximab in patients with chronic obstructive pulmonary disease, with percentage of sputum neutrophils as the primary endpoint.

METHODS

We performed an exploratory single-center, double-blind, placebo-controlled, randomized, phase 2 trial in which 22 current smokers with mild-to-moderate chronic obstructive pulmonary disease participated. Fourteen patients received three infusions of infliximab (5 mg/kg) at Weeks 0, 2, and 6, and eight patients received placebo infusions. Sputum samples, respiratory symptoms, quality of life, exhaled nitric oxide, lung function parameters, bronchial hyperresponsiveness, resting energy expenditure, and side effects were evaluated.

MEASUREMENTS AND MAIN RESULTS

This study did not show a positive short-term effect of infliximab on airway inflammation, lung function, resting energy expenditure, or quality of life. Exhaled nitric oxide increased significantly at Day 2, Week 6, and Week 8 in patients receiving infliximab compared with those receiving placebo. Eight patients in the infliximab group (vs. none in the placebo group) reported increased coughing, but no serious adverse events or increase in respiratory infections were reported during 9 weeks of follow-up.

CONCLUSIONS

In this short-term study, no clinically beneficial effects of infliximab were observed, and there were no significant safety issues. Definite conclusions concerning the effectiveness of infliximab treatment in chronic obstructive pulmonary disease await additional studies, including those with a larger number of patients with more advanced disease.

Oligoclonal CD4+ T cells in the lungs of patients with severe emphysema

RATIONALE

Within the lungs of patients with severe emphysema, inflammation continues despite smoking cessation. Foci of T lymphocytes in the small airways of patients with emphysema have been associated with disease severity. Whether these T cells play an important role in this continued inflammatory response is unknown.

OBJECTIVE

The aim of this study was to determine if T cells recruited to the lungs of subjects with severe emphysema contain oligoclonal T-cell populations, suggesting their accumulation in response to antigenic stimuli.

METHODS

Lung T-cell receptor (TCR) Vbeta repertoire from eight patients with severe emphysema and six control subjects was evaluated at the time of tissue procurement (ex vivo) and after 2 weeks of culture with interleukin 2 (in vitro). Junctional region nucleotide sequencing of expanded TCR-Vbeta subsets was performed.

RESULTS

No significantly expanded TCR-Vbeta subsets were identified in ex vivo samples. However, T cells grew from all emphysema (n = 8) but from only one of the control lung samples (n = 6) when exposed to interleukin 2 (p = 0.0013). Within the cultured cells, seven major CD4-expressing TCR-Vbeta subset expansions were identified from five of the patients with emphysema. These expansions were composed of oligoclonal populations of T cells that had already been expanded in vivo.

CONCLUSION

Severe emphysema is associated with inflammation involving T lymphocytes that are composed of oligoclonal CD4+ T cells. These T cells are accumulating in the lung secondary to conventional antigenic stimulation and are likely involved in the persistent pulmonary inflammation characteristic of severe emphysema.

Drugs in clinical development for chronic obstructive pulmonary disease

Many drugs may be potentially useful in the treatment of chronic obstructive pulmonary disease (COPD), but relatively few become available for human use due to lack of safety, lack of efficacy, or both. This is an inherent risk in the drug development process, which coupled with the limited understanding of the molecular pathogenesis of COPD, has produced a trend toward improving existing compounds rather than to develop new compounds. This review focuses on improved existing compounds and newly discovered compounds that are in clinical trials, but not yet marketed. The improved existing compounds include: isomers of the long-acting bronchodilators, once-daily beta2-adrenoceptor agonists, anticholinergics and corticosteroids. The pool of novel compounds is in constant fluctuation and comprises anti-inflammatory drugs, antioxidants, leukotriene modifiers and a number of compounds aimed at treating different aspects of COPD such as pulmonary hypertension and hypophosphatemia.

Association of current smoking with airway inflammation in chronic obstructive pulmonary disease and asymptomatic smokers

BACKGROUND

Inflammation in the airways and lung parenchyma underlies fixed airway obstruction in chronic obstructive pulmonary disease. The exact role of smoking as promoting factor of inflammation in chronic obstructive pulmonary disease is not clear, partly because studies often do not distinguish between current and ex-smokers.

METHODS

We investigated airway inflammation in sputum and bronchial biopsies of 34 smokers with chronic obstructive pulmonary disease (9 Global initiative for Chronic Obstructive Lung Disease stage 0, 9 stage I, 10 stage II and 6 stage III) and 26 asymptomatic smokers, and its relationship with past and present smoking habits and airway obstruction.

RESULTS

Neutrophil percentage, interleukin-8 and eosinophilic-cationic-protein levels in sputum were higher in chronic obstructive pulmonary disease (stage I-III) than asymptomatic smokers. Inflammatory cell numbers in bronchial biopsies were similar in both groups. Current smoking correlated positively with macrophages: in bronchial biopsies in both groups, and in sputum in chronic obstructive pulmonary disease. Pack-years smoking correlated positively with biopsy macrophages only in chronic obstructive pulmonary disease.

CONCLUSION

Inflammatory effects of current smoking may mask the underlying ongoing inflammatory process pertinent to chronic obstructive pulmonary disease. This may have implications for future studies, which should avoid including mixed populations of smokers and ex-smokers.

A randomized phase IIb trial of pulmicort turbuhaler (budesonide) in people with dysplasia of the bronchial epithelium

PURPOSE

Preclinical studies suggest that inhaled budesonide may be an effective chemopreventive agent for lung cancer. We conducted a phase IIb study to determine the effects of inhaled budesonide in smokers with bronchial dysplasia.

EXPERIMENTAL DESIGN

A total of 112 smokers with more than or equal to one site of bronchial dysplasia > 1.2 mm in size identified by autofluorescence bronchoscopy-directed biopsy was randomly assigned to receive placebo or budesonide (Pulmicort Turbuhaler) 800 microg twice daily inhalation for 6 months. The primary end point was change in the histopathologic grade on repeat biopsy of the same sites at the end of 6 months.

RESULTS

There were no significant differences in the regression or progression rates of bronchial dysplasia between the two groups. There was a statistically significant but modest decrease in p53 and BclII expression in the bronchial biopsies after 6 months of Pulmicort Turbuhaler versus placebo (P = 0.01 and P = 0.001, respectively). There was a small but statistically significant decrease in the proportion of computed tomography-detected lung nodules after Pulmicort Turbuhaler compared with placebo (P = 0.024).

CONCLUSIONS

Our results suggest that in smokers, inhaled budesonide in the dose of 1600 microg daily for 6 months had no effect in regression of bronchial dysplastic lesions or prevention of new lesions. Budesonide treatment resulted in a modest decrease in p53 and BclII protein expression in bronchial biopsies and a slightly higher rate of resolution of computed tomography-detected lung nodules. Whether budesonide truly has an effect in preneoplastic lesions in the peripheral airways and alveoli requires additional investigation.

Differences in airway remodeling between asthma and chronic obstructive pulmonary disease

The functional consequence of asthma and chronic obstructive pulmonary disease (COPD)is airflow limitation, which is mostly reversible in asthma and not fully reversible in COPD. In both diseases, inflammatory conditions are associated with cellular and structural changes,referred to as remodeling, and these structural changes may lead to thickening of the airway wall, thereby promoting airway narrowing and airflow limitation. However, the pattern of infiltrated cells and the pattern of structural changes occur differently in the two diseases. In asthma, CD4+, T lymphocytes, eosinophils, and mast cells are the predominant cells involved,whereas in COPD, CD8+, T lymphocytes, and macrophages are predominantly involved. In severe cases of asthma and COPD, neutrophil infiltration becomes evident. Regarding structural changes, epithelial injury and early thickening of reticular basement membrane are highly characteristic of the airway wall of asthmatics. Increases in airway smooth muscle mass occur in large airways of severe asthmatics and in small airways of patients with COPD. Thickening of the airway wall, goblet cell hyperplasia, mucous gland hypertrophy, and the luminal obstruction caused by inflammatory exudates and mucous are features of both asthma and COPD. Squamous epithelial metaplasia and airway wall fibrosis are commonly observed characteristics of COPD. Destruction and fibrosis of the alveolar wall occur in COPD but not in asthma. The remodeling processes accompanied by chronic inflammatory infiltrates interact in a complex fashion and contribute to the development of airflow limitation in both asthma and COPD.

The Interactions Between Cigarette Smoking and Reduced Lung Function on Systemic Inflammation

BACKGROUND

Low-grade systemic inflammation is commonly observed in conditions associated with reduced FEV(1). Active cigarette smoking, which is a leading risk factor for decreased FEV(1), can also independently induce systemic inflammation.

STUDY OBJECTIVES

To determine the independent contributions of active cigarette smoking and reduced FEV(1) (as well as their potential interactions) on systemic inflammation.

DESIGN

Cross-sectional survey.

SETTING

The US general population.

PARTICIPANTS

A total of 7,685 adult participants, >/= 40 years of age, in the Third National Health and Nutrition Examination Survey, who had acceptable data on spirometry and laboratory measurements such as serum C-reactive protein (CRP).

MEASUREMENTS

The participants were stratified into four equal groups (quartiles) based on the percent predicted FEV(1) values. Each group was further categorized as active smokers or nonsmokers according to serum cotinine level (ie, >/= 10 or < 10 ng/mL). Serum levels of CRP, plasma fibrinogen, blood leukocytes, and platelets were compared across the predicted FEV(1) quartile groups and across smoking status using multiple logistic regression models.

RESULTS

We found that active smoking by itself increased the odds of having elevated CRP levels by 63% (adjusted odds ratio [OR], 1.63; 95% confidence interval, 1.28 to 2.09). The adjusted OR for reduced FEV(1) was 2.27 (95% confidence interval, 1.92 to 2.70). Having both risk factors increased the OR to 3.31 (95% confidence interval, 2.73 to 4.02). Similar findings were observed for blood leukocytes and plasma fibrinogen.

CONCLUSION

These findings suggest an additive effect of active smoking and reduced FEV(1) on markers of systemic inflammation and suggest their potential interactions in the pathogenesis of systemic complications observed in patients with poor lung function.

Phosphodiesterase 4-selective inhibition: novel therapy for the inflammation of COPD

Chronic obstructive pulmonary disease (COPD), which is increasing in prevalence and a leading cause of death worldwide, is characterised by an 'abnormal' inflammatory response. There is a predominance of CD8(+) T cells, CD68(+) macrophages and, in exacerbations-neutrophils, in both conducting airways and lung parenchyma. Smoking is the most common etiological factor leading to COPD and smoking cessation is the most effective approach to the management of COPD, but it does not resolve the underlying inflammation of COPD, which persists, even in ex-smokers. The presence of mucosal inflammation serves as the rationale for anti-inflammatory therapy. However, while there are reductions in the numbers of mast cells following treatment with inhaled steroids, CD8(+), CD68(+) cells and neutrophils are refractory to such treatment, highlighting a need for additional, more targeted interventions. Phosphodiesterase 4 (PDE4) inhibitors are a promising and novel drug class that have potent activity against several key components of the inflammatory process in COPD. A recently published study has shown that the selective PDE4 inhibitor, cilomilast, reduces the numbers of bronchial mucosal CD8(+) and CD68(+) cells and neutrophils. This review focuses on the nature of the inflammation in COPD and considers how selective PDE4 inhibitors may optimize and advance our treatment of this chronic condition.

COPD, a multicomponent disease: implications for management

Chronic obstructive pulmonary disease (COPD) is a multicomponent disease. These components affect both the lungs and organs outside the lungs (the so-called systemic effects of COPD) and can be of either a structural (including airway remodelling, emphysema, skeletal muscle wasting) or functional nature (inflammation, apoptosis, senescence). Further, these components are interdependent in a closely linked 'vicious cycle'. Accordingly, optimal therapies should therefore aim to address more than one of these components to break such a cycle. This needs to be considered not only in the development of future treatments but also in the current clinical management of patients with COPD. In this paper, evidence that supports the concept that COPD is a multicomponent disease is presented. The effects of currently available therapeutic options, including long-acting anticholinergics and long-acting beta2-agonist/inhaled corticosteroid combination therapies, upon each of these components is reviewed. In addition, potential new avenues for drug development and improved patient care are highlighted. By developing a better understanding of how different therapies impact upon the 'vicious cycle' of COPD, treatment regimens can be optimised to provide the greatest benefits to patients.

Upper airway symptoms and quality of life in chronic obstructive pulmonary disease (COPD)

OBJECTIVE

To assess the impact on quality of life from upper airway symptoms in chronic obstructive pulmonary disease (COPD).

METHODS

Sixty-five patients with moderate-to-severe COPD were studied using the 20-item Sino-Nasal Outcome Test (SNOT-20) questionnaire, a validated disease-specific health-related quality of life tool for the assessment of rhinosinusitis. Patients also completed the St. George's Respiratory Questionnaire (SGRQ).

RESULTS

Eighty-eight percent of patients experienced nasal symptoms on most days of the week, most commonly rhinorrhoea. The mean SNOT-20 score of 1.24 demonstrates that nasal symptoms cause impairment to quality of life. The SNOT-20 score correlated with the number of chronic nasal symptoms (rho = 0.51, P < 0.01): the more daily nasal symptoms experienced, the greater the impact on health status. There was no significant correlation between SNOT-20 and SGRQ (r = 0.21, P = 0.09) suggesting that both upper and lower airway symptoms contribute to the total quality of life burden.

CONCLUSIONS

This is the first study to report on upper airway involvement in well characterised COPD patients using a previously validated assessment tool. Upper airway symptoms are frequent in these patients and cause impairment to the quality of life. These effects may not be detected using currently available quality of life tools that focus on lower respiratory tract symptoms.

Managing patients with recurrent acute exacerbations of chronic bronchitis: a common clinical problem

Chronic obstructive pulmonary disease (COPD) affects 15 million people and is the fourth leading cause of death in the United States. It places a considerable burden on the healthcare system, with exacerbations contributing to a significant proportion of this burden. Patients with recurrent exacerbation, who experience more than 2 exacerbations per year, are especially difficult to manage. Several potential host, pathogen, and treatment factors can be identified that contribute to recurrent exacerbation. Patients with recurrent exacerbations are often exposed to frequent courses of antimicrobials. Therefore, antimicrobial resistance among common bacterial pathogens is likely to be prevalent in this group of patients, and further complicates therapy in this already difficult-to-treat patient population. In the management of patients with recurrent exacerbation, one goal should be to decrease the frequency of exacerbations, for which several strategies are suggested. In this article, we will review available literature identified through an extensive search of Medline and PubMed on the characteristics and approach to management of these difficult-to-treat patients. There is a substantial need for more research to understand the etiology and identify efficacious interventions to reduce the frequency of exacerbations of COPD.

Chemokines in Bronchiolar Epithelium in the Development of Chronic Obstructive Pulmonary Disease

The inflammatory chemokines interleukin-8, macrophage inflammatory protein-1alpha, and monocyte chemoattractant protein-1, are reportedly involved in the pathogenesis of chronic obstructive pulmonary disease (COPD). Although bronchiolar epithelial cells and macrophages are known to be the cellular sources, the relative contribution of each cell type remains to be elucidated. In the present study, we first quantified cytokine mRNA in human bronchiolar epithelial cells and macrophages obtained using laser-capture microdissection and explored the relationship with early-stage COPD. Only in bronchiolar epithelial cells were interleukin-8, macrophage inflammatory protein-1alpha, and monocyte chemoattractant protein-1 mRNA levels higher in smokers with airflow limitation and/or emphysema than those in never-smokers or smokers without either airflow limitation or emphysema. No difference was observed in macrophages. Complementary DNA (cDNA) array further revealed the overexpression of CC chemokine receptor 2 in bronchiolar epithelial cells from smokers with airflow limitation and/or emphysema. This study supports the role of bronchiolar epithelium as the source of increased inflammatory chemokine levels in the early development of COPD and also demonstrates the potential use of laser-capture microdissection, combined with reverse transcriptase-polymerase chain reaction and cDNA microarrays, to investigate functional profiles of individual structural and inflammatory cells in human lungs.

Prospects for new drugs for chronic obstructive pulmonary disease

No currently available treatments have been shown to slow the progression of chronic obstructive pulmonary disease (COPD) or suppress the inflammation in small airways and lung parenchyma. However, several new treatments are in clinical development; some target the inflammatory process and others are directed against structural cells. A group of specific therapies are directed against the influx of inflammatory cells into the airways and lung parenchyma that occurs in COPD; these include agents directed against adhesion molecules and chemokines, as well as therapies to oppose tumour necrosis factor alpha and increase interleukin 10. Broad-range anti-inflammatory drugs are now in phase III development for COPD; they include inhibitors of phosphodiesterase 4. Other drugs that inhibit cell signalling include inhibitors of p38 mitogen-activated protein kinase, nuclear factor kappaB, and phosphoinositide-3-kinase gamma. More specific approaches are to give antioxidants, inhibitors of inducible nitric oxide synthase, and antagonists of leukotriene B4 receptor. Inhibitors of epidermal-growth-factor-receptor kinase and calcium-activated chloride channels have the potential to prevent overproduction of mucus. Therapy to inhibit fibrosis is being developed against transforming growth factor beta1 and protease-activated receptor 2. There is also a search for inhibitors of serine proteinases and matrix metalloproteinases to prevent lung destruction and the development of emphysema, as well as drugs such as retinoids that might even reverse this process. Effective delivery of drugs to the sites of disease in the peripheral lung is an important consideration, and there is a need for validated biomarkers and monitoring techniques in early clinical studies with new therapies for COPD.

Burden and clinical features of chronic obstructive pulmonary disease (COPD)

Chronic obstructive pulmonary disease (COPD) is a major cause of chronic morbidity and mortality and represents a substantial economic and social burden throughout the world. It is the fifth leading cause of death worldwide and further increases in its prevalence and mortality are expected in the coming decades. The substantial morbidity associated with COPD is often underestimated by health-care providers and patients; likewise, COPD is frequently underdiagnosed and undertreated. COPD develops earlier in life than is usually believed. Tobacco smoking is by far the major risk for COPD and the prevalence of the disease in different countries is related to rates of smoking and time of introduction of cigarette smoking. Contribution of occupational risk factors is quite small, but may vary depending on a country's level of economic development. Severe deficiency for alpha-1-antitrypsin is rare and the impact of other genetic factors on the prevalence of COPD has not been established. COPD should be considered in any patient presenting with cough, sputum production, or dyspnoea, especially if an exposure to risk factors for the disease has been present. Clinical diagnosis needs to be confirmed by standardised spirometric tests in the presence of not-fully-reversible airflow limitation. COPD is generally a progressive disease. Continued exposure to noxious agents promotes a more rapid decline in lung function and increases the risk for repeated exacerbations. Smoking cessation is the only intervention shown to slow the decline. If exposure is stopped, the disease may still progress due to the decline in lung function that normally occurs with aging, and some persistence of the inflammatory response.

Dietary fiber and reduced cough with phlegm: a cohort study in Singapore

Smoking is the major risk factor for chronic respiratory symptoms, but dietary factors may also play a role. Most studies of diet and lung disease have been cross-sectional and conducted in populations with a Western-style diet. We analyzed the relation between dietary intake at baseline and new onset of cough with phlegm in a population-based cohort of 63,257 middle-aged Chinese men and women initiated in Singapore between 1993 and 1998. Beginning in 1999, we ascertained respiratory symptoms by telephone interview and have identified 571 incident cases of cough with phlegm among the 49,140 cohort members with completed follow-up. Nonstarch polysaccharides, a major component of dietary fiber, total fruit, and soy isoflavones had the strongest associations. Odds ratios comparing highest and lowest quartiles after adjustment for age, sex, dialect group, total energy intake, and smoking were 0.61 (95% confidence interval [CI]: 0.47, 0.78; p for trend < 0.001) for nonstarch polysaccharides, 0.67 (95% CI: 0.52, 0.87; p for trend = 0.006) for fruit, and 0.67 (95% CI: 0.53, 0.86; p for trend = 0.001) for soy isoflavones. These data suggest that a diet high in fiber from fruit and, possibly, soyfoods may reduce the incidence of chronic respiratory symptoms. Associated nutrients, such as flavonoids, may contribute to this association.

Development of chronic airway obstruction in patients with eosinophilic bronchitis: a prospective follow-up study

STUDY OBJECTIVES

Eosinophilic bronchitis (EB) presents as a chronic cough and sputum eosinophilia without airflow limitation or bronchial hyperreactivity. Its long-term clinical course remains unknown. This study evaluated how frequently EB recurs and whether it develops chronic airway obstruction.

DESIGN

This study was a prospective analysis.

METHODS

Cough severity, FEV(1), provocative concentration of methacholine causing a 20% fall in FEV(1), and sputum eosinophil percentages were serially measured in 36 subjects for up to 48 months. All subjects inhaled corticosteroids until cough subsided.

RESULTS

Five of the twenty four follow-up subjects (21%) had a recurrent episode of EB 4 to 6 months after disappearance of the first episode of EB (recurrent eosinophilic bronchitis). Progressive FEV(1) reduction > 20% was observed in three of the subjects, including a subject with asthma developing at the ninth month. Nineteen subjects had no recurrence of cough (nonrecurrent eosinophilic bronchitis) and no progressive FEV(1) reduction > 20%. However, sputum eosinophilia recurred between 4 months and 24 months in 10 subjects. Mean values of FEV(1) at the ninth and 12th months of the study were significantly lower in the recurrent eosinophilic bronchitis group than in the nonrecurrent eosinophilic bronchitis group (p < 0.01).

CONCLUSION

These results suggest that repeated episode of EB is associated with the development of chronic airflow obstruction, including asthma.

Dissociation of lung function and airway inflammation in chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is defined by progressive, irreversible airflow limitation and an inflammatory response of the lungs, usually to cigarette smoke. However, COPD is a heterogeneous disease in terms of clinical, physiologic, and pathologic presentation. We aimed to evaluate whether airflow limitation, airway responsiveness, and airway inflammation are separate entities underlying the pathophysiology of COPD by using factor analysis. A total of 114 patients (99 males/15 females, age 62 +/- 8 years, 42 pack-years smoking, no inhaled or oral steroids > 6 months) with irreversible airflow limitation (postbronchodilator FEV(1) 63 +/- 9% predicted, FEV(1)/inspiratory vital capacity [IVC] 48 +/- 9%) and symptoms of chronic bronchitis or dyspnea were studied in a cross-sectional design. Postbronchodilator FEV(1) and FEV(1)/IVC, reversibility to inhaled beta(2)-agonists, diffusing capacity, provocative concentration of methacholine required to produce a 20% drop in FEV(1), total serum IgE, exhaled nitric oxide, and induced sputum cell counts (% eosinophils, % neutrophils) were collected. Factor analysis yielded 4 separate factors that accounted for 63.6% of the total variance. Factor 1 was comprised of FEV(1), FEV(1)/IVC, and residual volume/total lung capacity. Factor 2 included reversibility, IgE, provocative concentration of methacholine required to produce a 20% drop in FEV(1,) and diffusing capacity. Factor 3 contained exhaled nitric oxide and factor 4 included sputum % neutrophils and % eosinophils. We conclude that airflow limitation, airway inflammation, and features commonly associated with asthma are separate and largely independent factors in the pathophysiology of COPD.

Induced sputum CD8+ T-lymphocyte subpopulations in chronic obstructive pulmonary disease

BACKGROUND

Previous studies have shown that the inflammatory response to cigarette smoking differs between smokers who develop chronic obstructive pulmonary disease (COPD) and those who do not and that the CD8+ T-lymphocytes have been identified as a key player in this process. The aim of this study was to investigate further the role of CD8+ cells and their subtypes in sputum cells.

METHODS

Sputum induction was performed in 36 COPD patients, 25 smokers without COPD and 10 non-smoking healthy controls. After stimulation of sputum lymphocytes with phorbol-myristate-acetate, we used double immunocytochemical methods to identify CD4+, CD8+ cells and CD8+ INFgamma or IL4 cells (Tc1,Tc2).

RESULTS

COPD patients had an increased number of CD8+ cells in sputum as compared with smokers without COPD (P = 0.0001) and control subjects (P = 0.001). CD8+-IL4 cells were reduced both in COPD and in smokers without COPD compared to controls (P = 0.0001), while CD8+-IFNgamma cells were significantly reduced only in COPD (P = 0.001) as compared with controls. A significant (P = 0.02) relationship between the CD8+-IL4/CD8+-IFNgamma ratio and FEV1 (% pred) was found only in COPD patients.

CONCLUSION

These findings suggest that an imbalance both in T-lymphocyte subpopulation (CD4/CD8) and in CD8+ cell subsets (Tc1/Tc2) characterizes the inflammatory responses of smokers with established COPD.

Bronchodilator effect of zafirlukast in subjects with chronic obstructive pulmonary disease

Cysteinyl leukotrienes (LT) are involved in airway inflammation and mucus hypersecretion, characteristically present in asthma and chronic obstructive pulmonary disease (COPD). Zafirlukast is an LT receptor antagonist that improves airway function within 1-3 h after oral administration in subjects with chronic persistent asthma. Through a randomised, double-blind, crossover and placebo-controlled study, we assessed the short-term effects of zafirlukast in patients with severe COPD. We enrolled 23 subjects (seven women) aged 59.4 (1.67) yr [mean (SEM)] with a smoking history of 60.7 (5.2) pack-yr. At screening day the mean FEV(1)was 0.876 (0.72) l; FEV(1) % predicted=35 (3)% and 107 (14) ml increment post-salbutamol. They came two different days, apart from each other at least 72 h. After baseline spirometry, a single oral dose of 40 mg zafirlukast or the corresponding placebo was administered. FVC and FEV(1) was measured every 30 min until 2 hrs. On zafirlukast day, the mean FEV(1) at 90 min [0.813 (0.64) l] and the mean FVC at 90 min [1.76 (0.1) l] were significantly higher than the respective means at placebo day (mean FEV(1)=0.747 (0.55) l; mean FVC=1.63 (0.1) l; p<0.05 Tukey Kramer multiple comparisons test). The maximum mean increase in FEV(1) was 75 (19) ml. A positive correlation was found between absolute response to salbutamol in FEV(1) and the response to zafirlukast (r=0.41; p<0.04). In conclusion, these findings suggest that zafirlukast has a bronchodilator or antibronchoconstrictor effect in COPD patients with severe airflow limitation.

Elevated urinary 8-hydroxydeoxyguanosine, a biomarker of oxidative stress, and lack of association with antioxidant vitamins in chronic obstructive pulmonary disease

OBJECTIVE

The purpose of this study was to investigate whether patients with COPD are under oxidative stress and to elucidate the relationship between the level of oxidative stress and antioxidant vitamins.

METHODOLOGY

Nineteen male patients with COPD and 13 age- matched male control subjects were studied. Urinary 8-hydroxydeoxyguanosine (8-OHdG) concentrations were determined using an enzyme-linked immunosorbent assay kit and corrected for creatinine concentrations. Serum levels of vitamin C, alpha-tocopherol, and beta-carotene were determined by high performance liquid chromatography.

RESULTS

The median (interquartile range) 8-OHdG excretion was 8.1 ng/mg (5.3-10.9 ng/mg) in control subjects and 12.2 ng/mg (9.8-15.5 ng/mg) in COPD patients (P < 0.01). Urinary 8-OHdG levels were significantly elevated in ex-smokers in the COPD group compared with ex-smokers in the control group. Urinary 8-OHdG level was negatively correlated with FVC (r = -0.42, P = 0.016), FEV1 (r = -0.49, P = 0.0048), and oxygen tension in arterial blood (r = -0.41, P = 0.0005). No significant differences in antioxidant levels were demonstrated between the two groups. There were no significant correlations between urinary 8-OHdG excretion and the serum concentrations of antioxidant vitamins.

CONCLUSION

The burden of oxidative stress was observed to increase in COPD patients as judged by urinary 8-OHdG. A depletion of antioxidant vitamins in serum was not essential for this phenomenon. Elevated urinary 8-OHdG level may not be attributable to smoking status or to antioxidant vitamins in COPD.

Inhibitory capacity of different steroids on neutrophil migration across a bilayer of endothelial and bronchial epithelial cells

Neutrophil infiltration to the airway lumen is a common feature of respiratory inflammatory processes. The aim of this study was to evaluate whether different corticosteroids exert any selective effect on the migration of isolated neutrophils. A bilayer of cultured human endothelial and bronchial epithelial cells was used as a model for neutrophil migration through the blood-air barrier. Low spontaneous migration of neutrophils (2.8+/-0.9%, n=8; mean+/-S.E.M.) occurred, while in the absence of any steroid, a migration of 28.5+/-7.6% could be induced by lipopolysaccharide. Pre-incubation during 1 h of epithelial cells with dexamethasone, budesonide, or prednisolone (10(-10)-10(-4) M) showed in all instances a concentration-dependent inhibition following a bell-shaped curve. At 10(-7) M, both dexamethasone and budesonide were on the minimum effect peak of the bell-shaped curve. The peak for prednisolone was found at 10(-8) M. However, when steroid pre-incubation was extended to 4 h, a sigmoid curve was observed, with significant inhibition of migration at concentrations >10(-7) M. Steroids can inhibit neutrophil recruitment through two different pathways with distinct result, depending on the length of incubation time.

Relationship between chronic nasal and respiratory symptoms in patients with COPD

The relationship between the upper and lower airways in chronic obstructive pulmonary disease (COPD) is unknown. We examined the prevalence of chronic nasal symptoms and the correlation with lower respiratory symptoms and parameters of severity of COPD such as exacerbation frequency and spirometry. 61 COPD patients from the East London COPD cohort were studied. [Mean (SD) age 70 (6.96) years, FEV1 0.98 (0.38) l, FVC 2.45 (0.72) l, FEV1%Pred 37.0 (12.3), and 47.6 (31.8) smoking pack years, 14 current smokers, 36 males]. COPD patients had a high prevalence of nasal symptoms (75%), more than half reporting nasal discharge (52.5%) and sneezing (45.9%). Associations were found between nasal score and daily sputum production (P = 0.005) and post-nasal drip and sputum production (P = 0.046) with a trend to increased nasal symptoms in frequent exacerbators compared to infrequent exacerbators. No significant relationship was found between nasal symptoms and FEV1 or any other lower respiratory airway symptom. Associations between nasal and respiratory symptoms were found suggesting that there is a relationship between the upper and lower airway in COPD.

Induced sputum in the investigation of airway inflammation of COPD

During the last decade, the method of sputum induction (SI) has offered the opportunity to study inflammation in patients with chronic obstructive pulmonary disease (COPD). This paper reviews methodological aspects of SI and summarizes its uses in the research of inflammation in COPD, including sputum cellularity and soluble markers. SI is a relatively safe, reliable, and reproducible technique, used to investigate different aspects of airway inflammation. Although various methods of induction and processing have been proved safe and highly reproducible, a generally accepted method is needed. Sputum analysis has given evidence for increased numbers of macrophages and neutrophils in COPD patients compared to normal subjects. In some studies, increased numbers of eosinophils have been also reported. Changes in various mediators have been found in sputum supernatant of COPD patients (IL-8, LTB-4 and TNF-a). The clinical usefulness of the method in the follow-up of the disease has not been explored extensively. A number of observations in patients with different clinical characteristics could be proven useful in identifying patterns of inflammation associated with different prognosis. Finally, SI could also guide treatment; such as, sputum eosinophilia in COPD could predict response to inhaled corticosteroids.

ROS in the local and systemic pathogenesis of COPD

An imbalance between oxidants and antioxidants is proposed in the pathogenesis of COPD. Potential alterations responsible for an imbalance in oxidant production and intra- and extracellular antioxidant defense systems are discussed with respect to COPD-related changes in the pulmonary compartment. In line with the current view of COPD as a disease with multiple systemic consequences, there is increasing evidence that imbalances in the redox milieu extend beyond the diseased lung in COPD patients. Skeletal muscle dysfunction is often observed in COPD and may result from imbalances in the redox environment of skeletal muscle. Potential triggers of oxidative stress in the muscle compartment include inflammation and hypoxia, and local sources of reactive oxygen and nitrogen species are discussed, as well the mechanisms by which skeletal muscle trophical state, contractility and fatigability may be affected by oxidative stress, resulting in skeletal muscle dysfunction.

New concepts in chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is a leading cause of death and disability but has only recently been explored from a cellular and molecular perspective. In COPD, chronic inflammation leads to fixed narrowing of small airways and alveolar wall destruction (emphysema). This is characterized by increased numbers of alveolar macrophages, neutrophils, and cytotoxic T lymphocytes, and the release of multiple inflammatory mediators (lipids, chemokines, cytokines, growth factors). There is also a high level of oxidative stress, which may amplify this inflammation. There is increased elastolysis and probable involvement of matrix metalloproteinases. The inflammation and proteolysis in COPD is an amplification of the normal inflammatory response to cigarette smoke. Unlike asthma, this inflammation appears to be resistant to corticosteroids, prompting a search for novel anti-inflammatory therapies that may prevent the relentless progression of the disease.

Nasal neutrophil activity and mucinous secretory responsiveness in COPD

Patients with chronic obstructive pulmonary disease (COPD) frequently report nasal symptoms. In the present study, we have examined whether or not COPD is associated with any nasal inflammation. Plasma exudation evoked by histamine challenges has been employed to improve the recovery of inflammatory indices in nasal lavage fluids. In 23 COPD-patients and 26 healthy subjects, all without history or signs of allergic rhinitis, nasal polyposis, or chronic rhinosinusitis, nasal saline-lavages were performed with and without histamine. alpha2-Macroglobulin, fucose, eosinophil cationic protein (ECP) and myeloperoxidase (MPO) were determined as indices of plasma exudation, mucinous secretion, eosinophil activity and neutrophil activity, respectively. The difference in MPO-levels between the histamine and the saline lavage was greater in COPD patients compared with healthy subjects (P<0.05). Also, COPD patients reporting nasal symptoms presented an increase in MPO at histamine challenge (P<0.05, cf. saline) and greater differences in MPO and fucose, respectively, between the histamine and the saline lavage (P<0.05, cf. patients without symptoms). We conclude that COPD is not associated with any marked nasal inflammation. However, our observation on increased MPO-levels at histamine challenge suggests some degree of increased neutrophil activity in this condition. Furthermore, when associated with nasal symptoms, COPD may be associated with an increased nasal secretory responsiveness.

Airway bacterial load and FEV1 decline in patients with chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is characterized by an accelerated decline in lung function and progressive airway inflammation. Bacteria have been isolated from the lower airway of stable COPD patients, and airway inflammation has been related to bacterial load and type. The relationship between bacterial colonization, airway inflammation, and lung function decline remains uncertain. We studied 30 patients with COPD, mean (SD) FEV1 0.947 (0.329), 34.8% (13.6%) predicted, for 12 months. Sputum collected at recruitment and the end of the study was analyzed for cytokines and for quantitative bacteriology. The decline in FEV1 was 57.6 (137.6) ml year-1. Bacterial growth was identified in all subjects, with an initial count of 107.47(0.91) cfu ml-1 rising to 107.93(0.81) cfu ml-1 at the end of the study (p = 0.019). FEV1 decline was related to this increase in airway bacterial load (r = 0.59, p = 0.001). FEV1 decline was greater in subjects who exhibited a change in the colonizing bacterial type compared with those with persistence of a single bacterial species over the study period (p = 0.017). Higher sputum interleukin (IL-8) was associated with greater declines in FEV1 (p = 0.03). Rising airway bacterial load and species changes are associated with greater airway inflammation and accelerated decline in FEV1. Bacterial colonization in COPD is an important factor in disease progression.

Inhaled Corticosteroids in the Long-Term Management of Patients with Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is a major problem in the elderly population, with approximately 10% of the population affected. Since COPD is an inflammatory disorder of the pulmonary system, corticosteroids might be expected to improve clinical outcomes of the disease. Data from large, well designed randomised clinical trials in which approximately one third of patients were > or =65 years of age indicate that inhaled corticosteroids do not modify the natural history of COPD, as measured by the rate of decline in forced expiratory volume in 1 second (FEV1). However, these same studies also suggest that corticosteroids reduce the frequency of clinical exacerbations by nearly a third (compared with placebo). This beneficial effect is particularly pronounced among those with an FEV1 less than 50% of the predicted value. Withdrawal of inhaled corticosteroids, on the other hand, leads to increased symptoms and elevates the risk of exacerbations by 50% above baseline levels. Patients' health-related quality of life is also improved by the use of inhaled corticosteroids. It is clear that inhaled corticosteroids elevate the risk of thrush, dysphonia and skin bruising by 2-fold compared with placebo. In addition, the sum of evidence suggests a modest deleterious effect for inhaled corticosteroids on bone mineral density, especially for formulations that have an increased rate of systemic absorption. However, the clinical evidence of this observation is uncertain. The effect of inhaled corticosteroids on fracture risk is controversial with some observational studies suggesting a possible association. Whether inhaled corticosteroids increase the risk of ophthalmic complications (cataracts and glaucoma) is also uncertain. In conclusion, the current evidence indicates that inhaled corticosteroid therapy produces short- and long-term clinical benefits in COPD patients with moderate-to-severe disease and should be used as adjunctive therapy for elderly patients with COPD who experience frequent exacerbations or have moderately reduced lung function.

Local and systemic inflammation in patients with chronic obstructive pulmonary disease: soluble tumor necrosis factor receptors are increased in sputum

Chronic obstructive pulmonary disease (COPD) is characterized by significant chronic inflammation in the pulmonary compartment as well as in the circulation. This study aimed to elucidate the relationship between local and systemic inflammation in smoking-induced COPD by assessing levels of soluble (s) tumor necrosis factor (TNF) receptors, TNF-alpha, and interleukin-8 (IL-8) in induced sputum and in plasma. Sputum induction was performed in 18 subjects with COPD (FEV(1) 56% predicted) and 17 healthy smokers (FEV(1) 99% predicted). Patients with COPD showed significantly higher percentages of neutrophils and levels of sTNF-R55 and IL-8 in sputum as compared with control subjects, whereas sputum sTNF-R75 levels tended to be higher in COPD. Sputum TNF-alpha levels were similar in both groups. When comparing sTNF receptors in sputum and plasma, no direct correlations were found despite elevation of circulating sTNF-R75 levels in patients with COPD. In addition, sputum sTNF receptors were inversely related to the FEV(1) in patients with COPD, whereas circulating sTNF receptors were not, suggesting different regulation of inflammation in the pulmonary and systemic compartment. When subjects were divided according to their current smoking status, levels of sTNF-R55, sTNF-R75, and IL-8 in sputum were significantly elevated in ex-smoking versus currently smoking patients with COPD, suggesting ongoing inflammation in airways and circulation of patients with COPD after smoking cessation.

Safety of sputum induction in moderate-to-severe chronic obstructive pulmonary disease

This retrospective study was designed to evaluate the safety and efficacy of a bronchoprotective sputum induction protocol in moderate to severe chronic obstructive pulmonary disease (COPD). Forty-two adults with COPD (FEV1 = 51.7 +/- 3.2% predicted (mean +/- SEM)) under went sputum induction using a protocol designed to minimize hypertonic saline-induced bronchoconstriction. Hypertonic (3%) saline was used for subjects with FEV1 > or = 50%, and normal (0.9%) saline was used for subjects with FEV1 < 50%. Primary outcomes were change in peak flow, FEV1 and oxygen saturation. Mean decline in peak flow during sputum induction was 13.2 +/- 2.1%. FEV1 fell by 11.4 +/- 2.3%, an absolute fall of 0.14 +/- 0.031. Oxygen saturation did not change. A fall in peak flow of > or = 20% reliably predicted a fall in FEV1 of > or = 20%. Thirty-five of 42 subjects (83.3%) produced an acceptable sputum sample. Sputum eosinophil and neutrophil percentages were 2.8 +/- 0.9 and 73.0 +/- 3.0%, respectively, and were not correlated with changes in peak flow, FEV1 or oxygen saturation. A protocol for sputum induction which restricts the use of hypertonic saline based on lung function is both safe and effective in subjects with moderate to severe COPD.

New treatments for COPD

COPD is one of the most common diseases in the world, and there is a global increase in prevalence, but there are no drugs available at present that halt the relentless progression of this disease. However, a better understanding of the cellular and molecular mechanisms that are involved in the underlying inflammatory and destructive processes has revealed several new targets for which drugs are now in development, and the prospects for finding new treatments are good.

Remodeling in response to infection and injury. Airway inflammation and hypersecretion of mucus in smoking subjects with chronic obstructive pulmonary disease

Airway epithelium represents the first line of defense against toxic inhalants. In some subjects, cigarette smoking causes airway inflammation, hypersecretion of mucus, and poorly reversible airflow limitation through mechanisms that are still largely unknown. Likewise, it is unclear why only some smokers develop chronic obstructive pulmonary disease (COPD). Two cell types consistently result in relation to chronic airflow limitation in COPD: neutrophils and CD8(+) cells. Neutrophils are compartmentalized in the mucosal surface of the airways and air spaces, that is, the epithelium and lumen, whereas CD8(+) cells exhibit a more extensive distribution along the subepithelial zone of the airways and lung parenchyma, including alveolar walls and arteries. This pattern of inflammatory cell distribution is observed in mild or moderate COPD, and in patients who have developed COPD, it is not modified by smoking cessation. The number of neutrophils further increases in the submucosa of patients with severe COPD, suggesting a role for these cells in the progression of the disease. Hypersecretion of mucus is a major manifestation in COPD. Mucus is produced by bronchial glands and goblet cells lining the airway epithelium. Unlike mucous gland enlargement, greater mucosal inflammation is associated with sputum production. Whereas neutrophil infiltration of submucosal glands occurs only in smokers with COPD, goblet cell hyperplasia in peripheral airways occurs both in smokers with or without COPD, suggesting that the major determinant of goblet cell hyperplasia is cigarette smoke itself.