Azithromycin for prevention of exacerbations of COPD

Pharmacological treatment of chronic obstructive pulmonary disease: from evidence-based medicine to phenotyping

Chronic obstructive pulmonary disease (COPD) is characterized by large phenotype variability, reflected by a highly variable response to pharmacological treatment. Nevertheless, current guidelines suggest that patients with COPD of similar severity should be treated in the same way. The phenotype-based pharmacotherapeutic approach proposes bronchodilators alone in the nonfrequent exacerbator phenotype and a combination of bronchodilators and inhaled corticosteroids in patients with asthma-COPD overlap syndrome (ACOS) and moderate-to-severe exacerbator phenotype. The clinical importance of phenotypes is changing the paradigm of COPD management from evidence-based to personalized medicine. However, the personalized pharmacological strategy of COPD has to be validated in future clinical studies.

The role of the microbiome in exacerbations of chronic lung diseases

Culture-independent microbiological techniques have shown a previously unappreciated complexity to the bacterial microbiome of the respiratory tract that forces reconsideration of the interactions between host, bacteria, and the pathogenesis of exacerbations of chronic lung disease. The composition of the lung microbiome is determined by microbial immigration, elimination, and relative growth rates of its members. All these factors change dramatically in chronic lung disease and further during exacerbations. Exacerbations lack the features of bacterial infections, including increased bacterial burden and decreased diversity of microbial communities. We propose that exacerbations are occasions of respiratory tract dysbiosis--a disorder of the respiratory tract microbial ecosystem with negative effects on host biology. Respiratory tract dysbiosis provokes a dysregulated host immune response, which in turn alters growth conditions for microbes in airways, promoting further dysbiosis and perpetuating a cycle of inflammation and disordered microbiota. Differences in the composition of baseline respiratory tract microbiota might help to explain the so-called frequent-exacerbator phenotype observed in several disease states, and might provide novel targets for therapeutic intervention.

The effect of azithromycin in adults with stable neutrophilic COPD: a double blind randomised, placebo controlled trial

Background

Chronic Obstructive Pulmonary Disease (COPD) is a progressive airway disease characterised by neutrophilic airway inflammation or bronchitis. Neutrophilic bronchitis is associated with both bacterial colonisation and lung function decline and is common in exacerbations of COPD. Despite current available therapies to control inflammation, neutrophilic bronchitis remains common. This study tested the hypothesis that azithromycin treatment, as an add-on to standard medication, would significantly reduce airway neutrophil and neutrophils chemokine (CXCL8) levels, as well as bacterial load. We conducted a randomised, double-blind, placebo-controlled study in COPD participants with stable neutrophilic bronchitis.

Methods

Eligible participants (n = 30) were randomised to azithromycin 250 mg daily or placebo for 12 weeks in addition to their standard respiratory medications. Sputum was induced at screening, randomisation and monthly for a 12 week treatment period and processed for differential cell counts, CXCL8 and neutrophil elastase assessment. Quantitative bacteriology was assessed in sputum samples at randomisation and the end of treatment visit. Severe exacerbations where symptoms increased requiring unscheduled treatment were recorded during the 12 week treatment period and for 14 weeks following treatment. A sub-group of participants underwent chest computed tomography scans (n = 15).

Results

Nine participants with neutrophilic bronchitis had a potentially pathogenic bacteria isolated and the median total bacterial load of all participants was 5.22×10⁷ cfu/mL. Azithromycin treatment resulted in a non-significant reduction in sputum neutrophil proportion, CXCL8 levels and bacterial load. The mean severe exacerbation rate was 0.33 per person per 26 weeks in the azithromycin group compared to 0.93 exacerbations per person in the placebo group (incidence rate ratio (95%CI): 0.37 (0.11,1.21), p = 0.062). For participants who underwent chest CT scans, no alterations were observed.

Conclusions

In stable COPD with neutrophilic bronchitis, add-on azithromycin therapy showed a trend to reduced severe exacerbations sputum neutrophils, CXCL8 levels and bacterial load. Future studies with a larger sample size are warranted.

Trial Registration

Australian New Zealand Clinical Trials Registry ACTRN12609000259246

Prevention of infections during primary immunodeficiency

Because infectious diseases are a major source of morbidity and mortality in the majority of patients with primary immunodeficiencies (PIDs), the application of a prophylactic regimen is often necessary. However, because of the variety of PIDs and pathogens involved, and because evidence is scarce, practices are heterogeneous. To homogenize practices among centers, the French National Reference Center for PIDs aimed at elaborating recommendations for anti-infectious prophylaxis for the most common PIDs. We performed a literature review of infectious complications and prophylactic regimens associated with the most frequent PIDs. Then, a working group including different specialists systematically debated about chemoprophylaxis, immunotherapy, immunization, and recommendations for patients. Grading of prophylaxis was done using strength of recommendations (decreasing from A to D) and evidence level (decreasing from I to III). These might help infectious diseases specialists in the management of PIDs and improving the outcome of patients with PIDs.

Biological clustering supports both "Dutch" and "British" hypotheses of asthma and chronic obstructive pulmonary disease

BACKGROUND

Asthma and chronic obstructive pulmonary disease (COPD) are heterogeneous diseases.

OBJECTIVE

We sought to determine, in terms of their sputum cellular and mediator profiles, the extent to which they represent distinct or overlapping conditions supporting either the "British" or "Dutch" hypotheses of airway disease pathogenesis.

METHODS

We compared the clinical and physiological characteristics and sputum mediators between 86 subjects with severe asthma and 75 with moderate-to-severe COPD. Biological subgroups were determined using factor and cluster analyses on 18 sputum cytokines. The subgroups were validated on independent severe asthma (n = 166) and COPD (n = 58) cohorts. Two techniques were used to assign the validation subjects to subgroups: linear discriminant analysis, or the best identified discriminator (single cytokine) in combination with subject disease status (asthma or COPD).

RESULTS

Discriminant analysis distinguished severe asthma from COPD completely using a combination of clinical and biological variables. Factor and cluster analyses of the sputum cytokine profiles revealed 3 biological clusters: cluster 1: asthma predominant, eosinophilic, high TH2 cytokines; cluster 2: asthma and COPD overlap, neutrophilic; cluster 3: COPD predominant, mixed eosinophilic and neutrophilic. Validation subjects were classified into 3 subgroups using discriminant analysis, or disease status with a binary assessment of sputum IL-1β expression. Sputum cellular and cytokine profiles of the validation subgroups were similar to the subgroups from the test study.

CONCLUSIONS

Sputum cytokine profiling can determine distinct and overlapping groups of subjects with asthma and COPD, supporting both the British and Dutch hypotheses. These findings may contribute to improved patient classification to enable stratified medicine.

Is there a role for macrolides in severe asthma?

PURPOSE OF REVIEW

Severe asthma is a heterogeneous syndrome, encompassing several distinct clinical phenotypes. Different molecular and cellular pathways or endotypes determine the type of underlying airway inflammation in patients with severe asthma, which can be categorized as eosinophilic asthma (allergic and nonallergic) or noneosinophilic asthma (neutrophilic and paucigranulocytic). In this review, we discuss the potential role of macrolides in the treatment of severe asthma in adults.

RECENT FINDINGS

Maintenance treatment with low-dose macrolides such as erythromycin and azithromycin provides clinical benefit in several chronic neutrophilic airway diseases, including cystic fibrosis (CF), non-CF bronchiectasis and exacerbation-prone chronic obstructive pulmonary disease. Although several short-term studies of macrolides in mild-to-moderate asthma have failed to improve lung function, the AzIthromycin in Severe Asthma trial has demonstrated a significant reduction in the rate of exacerbations in patients with exacerbation-prone noneosinophilic severe asthma. As chronic macrolide use is associated with the risks of population antimicrobial resistance, this add-on treatment should be restricted to severe asthma patients at greatest unmet need despite optimal asthma management.

SUMMARY

Further clinical, translational and basic research is needed to better phenotype patients with severe asthma, to determine the risk-benefit ratio of macrolide maintenance treatment in neutrophilic severe asthma and to elucidate the principal mechanisms of action of macrolides.

Macrolide antibiotics and the risk of cardiac arrhythmias

Randomized, controlled trials have demonstrated that chronic therapy with macrolide antibiotics reduces the morbidity of patients with cystic fibrosis, non-cystic fibrosis bronchiectasis, chronic obstructive pulmonary disease, and nontuberculous mycobacterial infections. Lower levels of evidence indicate that chronic macrolides are also effective in treating patients with panbronchiolitis, bronchiolitis obliterans, and rejection after lung transplant. Macrolides are known to cause torsade des pointes and other ventricular arrhythmias, and a recent observational study prompted the FDA to strengthen the Warnings and Precautions section of azithromycin drug labels. This summary describes the electrophysiological effects of macrolides, reviews literature indicating that the large majority of subjects experiencing cardiac arrhythmias from macrolides have coexisting risk factors and that the incidence of arrhythmias in absence of coexisting risk factors is very low, examines recently published studies describing the relative risk of arrhythmias from macrolides, and concludes that this risk has been overestimated and suggests an approach to patient evaluation that should reduce the relative risk and the incidence of arrhythmias to the point that chronic macrolides can be used safely in the majority of subjects for whom they are recommended.

Predictors of chronic obstructive pulmonary disease exacerbation reduction in response to daily azithromycin therapy

RATIONALE

Daily azithromycin decreases acute exacerbations of chronic obstructive pulmonary disease (AECOPD), but long-term side effects are unknown.

OBJECTIVES

To identify the types of exacerbations most likely to be reduced and clinical subgroups most likely to benefit from azithromycin, 250 mg daily, added to usual care.

METHODS

Enrollment criteria included irreversible airflow limitation and AECOPD requiring corticosteroids, emergency department visit, or hospitalization in the prior year or use of supplemental oxygen. Recurrent events and cumulative incidence analyses compared treatment received for AECOPD by randomization group, stratified by subgroups of interest. Cox proportional hazards models estimated treatment effects in subgroups adjusted for age, sex, smoking status, FEV1% predicted, concomitant COPD medications, and oxygen use.

MEASUREMENTS AND MAIN RESULTS

Azithromycin was most effective in reducing AECOPD requiring both antibiotic and steroid treatment (n = 1,113; cumulative incidence analysis, P = 0.0002; recurrent events analysis, P = 0.002). No difference in treatment response by sex (P = 0.75), presence of chronic bronchitis (P = 0.19), concomitant inhaled therapy (P = 0.29), or supplemental oxygen use (P = 0.23) was observed. Older age and milder Global Initiative for Chronic Obstructive Lung Disease stage were associated with better treatment response (P = 0.02 and 0.04, respectively). A significant interaction between treatment and current smoking was seen (P = 0.03) and azithromycin did not reduce exacerbations in current smokers (hazard ratio, 0.99; 95% confidence interval, 0.71-1.38; P = 0.95).

CONCLUSIONS

Azithromycin is most effective in preventing AECOPD requiring both antibiotic and steroid treatment. Adjusting for confounders, we saw no difference in efficacy by sex, history of chronic bronchitis, oxygen use, or concomitant COPD therapy. Greater efficacy was seen in older patients and milder Global Initiative for Chronic Obstructive Lung Disease stages. We found little evidence of treatment effect among current smokers. Clinical trial registered with www.clinicaltrials.gov (NCT0011986 and NCT00325897).

Evidence of mycobacterial disease in COPD patients with lung volume reduction surgery; the importance of histological assessment of specimens: a cohort study

Background

Patients with COPD are at risk of non-tuberculous mycobacterial infection (NTM). This study examined the histology of lung tissue from COPD patients following lung volume reduction with particular focus on evidence of mycobacterial infection.

Methods

Retrospective histological study of 142 consecutive lung volume reduction surgical specimens (126 separate patients) at Royal Brompton Hospital between 2000 – 2013, with prospectively collected preoperative data on exacerbation rate, lung function and body mass index.

Results

92% of patients had at least one other histological diagnosis in addition to emphysema. 10% of specimens had histological evidence of mycobacterial infection, one with co-existent aspergilloma. Mycobacteria were only identified in those patients with granulomas that were necrotising. These patients had higher exacerbation rates, lower TLCO and FEV₁.

Conclusion

A proportion of severe COPD patients will have evidence of mycobacterial infection despite lack of clinical and radiological suspicion. This may have implications for long-term management of these patients.

COPD 2013: an update on treatment and newly approved medications for pharmacists

OBJECTIVES

To educate pharmacists about the Global Strategy for the Diagnosis, Management, and Prevention of Chronic Obstructive Pulmonary Disease (GOLD) guidelines for treatment of chronic obstructive pulmonary disease (COPD), newly approved medications, and recent developments since the guidelines were published.

SUMMARY

The evidence-based GOLD guidelines provide recommendations for clinicians managing patients with COPD. These guidelines were revised most recently in 2013. Three new medications (indacaterol maleate, aclidinium bromide, and fluticasone furoate/vilanterol) have been approved in the previous 2 years. Adding to the armamentarium of medications for treating COPD is useful. Studies also have been conducted to determine which inhaled agents are preferred for use when long-acting bronchodilators are needed as mono- and combination therapy. In addition, 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors and macrolides are being studied for use in COPD. An extensive COPD pipeline consists of many oral and inhaled medications, including olodaterol and glycopyrronium maleate, which are in Phase III clinical trials. Medication adherence is a very important piece of COPD management. Pharmacists play an integral role in drug selection and patient education to ensure the best possible outcomes.

CONCLUSION

The GOLD guidelines represent the standard of care for COPD management. New drug approvals and recent research may affect practitioner choices in managing the disease. Pharmacists can improve medication adherence and selection in order to maximize therapeutic effectiveness and ensure that patients are using inhalation delivery devices optimally.

Tailoring of corticosteroids in COPD management

This literature review updates the reader on the new studies regarding steroid therapy over the last year in stable COPD and in exacerbations. In stable COPD, we critique the 2011 update and 2013 revision of the GOLD guidelines, discuss why combining inhaled corticosteroids (ICS) with long-acting beta-agonists (LABA) (ICS/LABA) is preferable over LABA alone and review the literature for intraclass differences, finding that the evidence does not clearly support superiority of any particular ICS/LABA. We also address other comparisons against ICS/LABA, including triple therapy. We briefly review which type of inhaler should be chosen. For exacerbations, we report the REDUCE trial findings favouring a 5-day course of systemic steroids, and other trials addressing which steroid and route to use, including in an intensive care setting. Lastly, the future lies in new anti-inflammatories and re-phenotyping the heterogeneous amalgamation of COPD. A Spanish guideline recommends distinguishing steroid-responsive eosinophilic exacerbators from other phenotypes.

Azithromycin inhibits nuclear factor-κB activation during lung inflammation: an in vivo imaging study

We studied in vivo the potential involvement of nuclear factor-κB (NF-κB) pathway in the molecular mechanism of the anti-inflammatory and immunomodulatory activity of azithromycin in the lung. Mice transiently transfected with the luciferase gene under the control of a NF-κB responsive element were used to assess in vivo NF-κB activation by bioluminescence imaging. Bioluminescence as well as inflammatory cells and concentrations of proinflammatory cytokines in bronchoalveolar lavage fluids, were monitored in an acute model of pulmonary inflammation resulting from intratracheal instillation of lipopolysaccharide. Lipopolysaccharide (LPS) instillation induced a marked increase in lung bioluminescence in mice transiently transfected with the luciferase gene under the control of an NF-κB responsive element, with significant luciferase expression in resident cells such as endothelial and epithelial cells, as assessed by duoplex immunofluorescence staining. Activation of NF-κB and inflammatory cell lung infiltration linearly correlated when different doses of bortezomib were used to inhibit NF-κB activation. Pretreatment with azithromycin significantly decreased lung bioluminescence and airways cell infiltration induced by LPS, also reducing proinflammatory cytokines concentrations in bronchoalveolar lavages and inhibiting NF-κB nuclear translocation. The results obtained using a novel approach to monitor NF-κB activation, provided, for the first time, in vivo evidence that azithromycin treatment results in pulmonary anti-inflammatory activity associated with the inhibition of NF-κB activation in the lung.

COPD-related bronchiectasis; independent impact on disease course and outcomes

BACKGROUND

COPD and radiographic bronchiectasis frequently coexist but the effect of this on the clinical course of COPD is not fully understood. We determined the impact of bronchiectasis on clinical outcomes in COPD patients, independent of coexisting emphysema and bronchial wall thickening (BWT).

METHODS

COPD patients admitted with first exacerbation 1998-2008 were identified retrospectively using ICD10 codes J44.0,1,8,9. Patients with suitable CT scans were graded for severity of bronchiectasis, emphysema and BWT on a 5 point scale (0-absent, 1-minor, 2-mild, 3-moderate, 4-severe).

RESULTS

406 patients (71 ± 11 years, 56% male, FEV1 52 ± 23% predicted) were included; 278 (69%) patients had bronchiectasis: minor, 112 (40%); mild, 81 (29%); moderate, 62 (22%); severe 23 (8%). Bronchiectasis severity correlated with severity of BWT (p < 0.001) but not emphysema (p = 0.090). Bronchiectasis independently determined sputum isolation of Pseudomonas aeruginosa (Odds ratio (OR) 1.39 (95% CI 1.07 to 1.80), p = 0.013) and atypical mycobacteria (OR 2.44 (95% CI 1.04 to 5.69), p = 0.040), annual respiratory admissions (p = 0.044) and inpatient days (p < 0.001), but did not predict survival (p = 0.256).

CONCLUSIONS

Radiographic bronchiectasis in COPD patients is associated with increased respiratory infection and hospitalisation, independent of coexisting emphysema and BWT. COPD-related bronchiectasis is therefore an important diagnosis with potential implications for treatment.

The pharmacological approach to the elderly COPD patient

The elderly patient (65 years and older) with chronic obstructive pulmonary disease (COPD) can be a challenge to the clinician. This begins with the correct and early diagnosis, the assessment of disease severity, recognizing complicating comorbidities, determining the burden of symptoms, and monitoring the frequency of acute exacerbations. Comprehensive management of COPD in the elderly patient should improve health-related quality of life, lung function, reduce exacerbations, and promote patient compliance with treatment plans. Only smoking cessation and oxygen therapy in COPD patients with hypoxemia reduce mortality. Bronchodilators, corticosteroids, methylxanthines, phosphodiesterase-4 inhibitors, macrolide antibiotics, mucolytics, and pulmonary rehabilitation improve some outcome measures such as spirometry measures and the frequency of COPD exacerbations without improving mortality. International treatment guidelines to reduce symptoms and reduce the risk of acute exacerbations exist. Relief of dyspnea and control of anxiety are important. The approach to each patient is best individualized. Earlier use of palliative care should be considered when traditional pharmacotherapy fails to achieve outcome measures and before consideration of end-of-life issues.

Impact of macrolide therapy in patients hospitalized with Pseudomonas aeruginosa community-acquired pneumonia

BACKGROUND

Several studies have described a clinical benefit of macrolides due to their immunomodulatory properties in various respiratory diseases. We aimed to assess the effect of macrolide therapy on mortality in patients hospitalized for Pseudomonas aeruginosa community-acquired pneumonia (CAP).

METHODS

We performed a retrospective population-based study of &gt; 150 hospitals in the US Veterans Health Administration. Patients were included if they had a diagnosis of CAP and P aeruginosa was identified as the causative pathogen. Patients with health-care-associated pneumonia and immunosuppression were excluded. Macrolide therapy was considered when administered within the first 48 h of admission. Univariate and multivariable analyses were performed using 30-day mortality as the dependent measure.

RESULTS

We included 402 patients with P aeruginosa CAP, of whom 171 (42.5%) received a macrolide during the first 48 h of admission. These patients were older and white. Macrolide use was not associated with lower 30-day mortality (hazard ratio, 1.14; 95% CI, 0.70-1.83; P = .5). In addition, patients treated with macrolides had no differences in ICU admission, use of mechanical ventilation, use of vasopressors, and length of stay (LOS) compared with patients not treated with macrolides. A subgroup analysis among patients with P aeruginosa CAP in the ICU showed no differences in baseline characteristics and outcomes.

CONCLUSIONS

Macrolide therapy in the first 48 h of admission is not associated with decreased 30-day mortality, ICU admission, need for mechanical ventilation, and LOS in hospitalized patients with P aeruginosa CAP. Larger cohort studies should address the benefit of macrolides as immunomodulators in patients with P aeruginosa CAP.

The role of macrolides in asthma: current evidence and future directions

Macrolides, such as clarithromycin and azithromycin, possess antimicrobial, immunomodulatory, and potential antiviral properties. They represent a potential therapeutic option for asthma, a chronic inflammatory disorder characterised by airway hyper-responsiveness that leads to recurrent episodes of wheezing, breathlessness, chest tightness, and coughing. Results from clinical trials, however, have been contentious. The findings could be confounded by many factors, including the heterogeneity of asthma, treatment duration, dose, and differing outcome measures. Recent evidence suggests improved effectiveness of macrolides in patients with sub-optimally controlled severe neutrophilic asthma and in asthma exacerbations. We examine the evidence from clinical trials and discuss macrolide properties and their relevance to the pathophysiology of asthma. At present, the use of macrolides in chronic asthma or acute exacerbations is not justified. Further work, including proteomic, genomic, and microbiome studies, will advance our knowledge of asthma phenotypes, and help to identify a macrolide-responsive subgroup. Future clinical trials should target this subgroup and place emphasis on clinically relevant outcomes such as asthma exacerbations.

Simvastatin for the prevention of exacerbations in moderate-to-severe COPD

BACKGROUND

Retrospective studies have shown that statins decrease the rate and severity of exacerbations, the rate of hospitalization, and mortality in chronic obstructive pulmonary disease (COPD). We prospectively studied the efficacy of simvastatin in preventing exacerbations in a large, multicenter, randomized trial.

METHODS

We designed the Prospective Randomized Placebo-Controlled Trial of Simvastatin in the Prevention of COPD Exacerbations (STATCOPE) as a randomized, controlled trial of simvastatin (at a daily dose of 40 mg) versus placebo, with annual exacerbation rates as the primary outcome. Patients were eligible if they were 40 to 80 years of age, had COPD (defined by a forced expiratory volume in 1 second [FEV1] of less than 80% and a ratio of FEV1 to forced vital capacity of less than 70%), and had a smoking history of 10 or more pack-years, were receiving supplemental oxygen or treatment with glucocorticoids or antibiotic agents, or had had an emergency department visit or hospitalization for COPD within the past year. Patients with diabetes or cardiovascular disease and those who were taking statins or who required statins on the basis of Adult Treatment Panel III criteria were excluded. Participants were treated from 12 to 36 months at 45 centers.

RESULTS

A total of 885 participants with COPD were enrolled for approximately 641 days; 44% of the patients were women. The patients had a mean (±SD) age of 62.2±8.4 years, an FEV1 that was 41.6±17.7% of the predicted value, and a smoking history of 50.6±27.4 pack-years. At the time of study closeout, the low-density lipoprotein cholesterol levels were lower in the simvastatin-treated patients than in those who received placebo. The mean number of exacerbations per person-year was similar in the simvastatin and placebo groups: 1.36±1.61 exacerbations and 1.39±1.73 exacerbations, respectively (P=0.54). The median number of days to the first exacerbation was also similar: 223 days (95% confidence interval [CI], 195 to 275) and 231 days (95% CI, 193 to 303), respectively (P=0.34). The number of nonfatal serious adverse events per person-year was similar, as well: 0.63 events with simvastatin and 0.62 events with placebo. There were 30 deaths in the placebo group and 28 in the simvastatin group (P=0.89).

CONCLUSIONS

Simvastatin at a daily dose of 40 mg did not affect exacerbation rates or the time to a first exacerbation in patients with COPD who were at high risk for exacerbations. (Funded by the National Heart, Lung, and Blood Institute and the Canadian Institutes of Health Research; STATCOPE ClinicalTrials.gov number, NCT01061671.).

Long-term, low-dose erythromycin monotherapy for Mycobacterium avium complex lung disease: a propensity score analysis

Multidrug regimens are initially withheld in mild cases of pulmonary Mycobacterium avium complex (MAC) disease. Based on the anti-inflammatory effects of macrolides, some patients are treated with erythromycin, which does not appear to exhibit cross-resistance with clarithromycin in MAC. The aim of this study was to evaluate the effects and adverse events of erythromycin monotherapy in patients with pulmonary MAC disease. This was a retrospective propensity score analysis consisting of 31 patients treated with erythromycin alone and 72 patients on conservative therapy, all of whom met the ATS/IDSA criteria for pulmonary MAC disease. The primary outcome was exacerbation requiring administration of a multidrug regimen. The secondary outcome was the rate of response to the multidrug regimens after exacerbation as a surrogate variable for cross-resistance to clarithromycin. As a result, erythromycin monotherapy was found to be likely to suppress exacerbation throughout the 7-year observation period after the diagnosis of pulmonary MAC disease (P=0.045, Breslow test). Multivariate analysis showed that erythromycin tended to prevent exacerbation, albeit statistically insignificantly (hazard ratio=0.495, 95% confidence interval 0.198-1.235; P=0.132). In addition, the rate of response to the multidrug regimens after exacerbation in the erythromycin group (56%; 5/9) was similar to that observed in the control group (62%; 13/21) (P=0.528). Erythromycin monotherapy for patients with pulmonary MAC disease may have the potential to suppress exacerbation without inducing cross-resistance to clarithromycin. However, further prospective studies are needed to microbiologically verify the effectiveness and potential for cross-resistance of these drugs.

Antibiotic prophylaxis in COPD: Why, when, and for whom?

One of the main goals of treatment of chronic obstructive pulmonary disease (COPD) is the prevention of exacerbations. Bronchodilators and anti-inflammatories are the first line therapy for treatment of COPD; however, these drugs are not effective in suppressing all infective exacerbations. In fact, the use of inhaled corticosteroids in patients with COPD and chronic bronchial infection may even increase the bacterial load in the airways and increase the risk of pneumonia. In this context, the use of long-term or intermittent antibiotic treatment has shown to prevent COPD exacerbations and hospitalizations. These effects may be achieved by reducing bacterial load in the airways in stable state and/or bronchial inflammation. The drugs more extensively studied are macrolides, followed by quinolones. The long-term use of antibiotics is associated with an increased risk of potentially serious adverse events and development of bacterial resistance. Therefore, the indication of long-term antibiotic therapy must be determined on a case by case basis taking into account the potential risks and benefits. In general, this treatment may be indicated in patients with severe or very severe COPD with frequent or severe exacerbations despite optimal pharmacological and non pharmacological treatment. These patients should be carefully monitored based on clinical and microbiological assessments. The most appropriate drug and regime administration, as well as the optimal duration of therapy are issues that still require further investigation.

A Decade of National Heart, Lung, and Blood Institute Programs Supporting COPD Research and Education

The past decade of research in chronic obstructive pulmonary disease (COPD) has seen a new age of understanding both pathogenic mechanisms and clinical manifestations of the disease. The National Heart, Lung, and Blood Institute (NHLBI) has helped guide this progress with a series of initiatives to stimulate COPD research in various ways. These initiatives were designed to promote a precision medicine approach to treating COPD, one that takes advantage of targeting particular molecular pathways and the individual pathobiologies of the diversity of COPD patients. This review describes the strategic objectives of these initiatives, as well as some of their observed and anticipated outcomes. In addition, we address parallel steps NHLBI has taken to promote COPD awareness among the public. As we look toward the immediate future of COPD research and education, we see a time of great progress in terms of understanding and treatment. Furthermore, while this remains a debilitating and disturbingly prevalent disease, as NHLBI looks even farther ahead, we envision emerging efforts toward COPD prevention.

Azithromycin maintenance treatment in patients with frequent exacerbations of chronic obstructive pulmonary disease (COLUMBUS): a randomised, double-blind, placebo-controlled trial

BACKGROUND

Macrolide resistance is an increasing problem; there is therefore debate about when to implement maintenance treatment with macrolides in patients with chronic obstructive pulmonary disease (COPD). We aimed to investigate whether patients with COPD who had received treatment for three or more exacerbations in the previous year would have a decrease in exacerbation rate when maintenance treatment with azithromycin was added to standard care.

METHODS

We did a randomised, double-blind, placebo-controlled, single-centre trial in The Netherlands between May 19, 2010, and June 18, 2013. Patients (≥18 years) with a diagnosis of COPD who had received treatment for three or more exacerbations in the previous year were randomly assigned, via a computer-generated randomisation sequence with permuted block sizes of ten, to receive 500 mg azithromycin or placebo three times a week for 12 months. Randomisation was stratified by use of long-term, low-dose prednisolone (≤10 mg daily). Patients and investigators were masked to group allocation. The primary endpoint was rate of exacerbations of COPD in the year of treatment. Analysis was by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00985244.

FINDINGS

We randomly assigned 92 patients to the azithromycin group (n=47) or the placebo group (n=45), of whom 41 (87%) versus 36 (80%) completed the study. We recorded 84 exacerbations in patients in the azithromycin group compared with 129 in those in the placebo group. The unadjusted exacerbation rate per patient per year was 1·94 (95% CI 1·50-2·52) for the azithromycin group and 3·22 (2·62-3·97) for the placebo group. After adjustment, azithromycin resulted in a significant reduction in the exacerbation rate versus placebo (0·58, 95% CI 0·42-0·79; p=0·001). Three (6%) patients in the azithromycin group reported serious adverse events compared with five (11%) in the placebo group. During follow-up, the most common adverse event was diarrhoea in the azithromycin group (nine [19%] patients vs one [2%] in the placebo group; p=0·015).

INTERPRETATION

Maintenance treatment with azithromycin significantly decreased the exacerbation rate compared with placebo and should therefore be considered for use in patients with COPD who have the frequent exacerbator phenotype and are refractory to standard care.

FUNDING

SoLong Trust.

Predictors of exacerbation frequency in chronic obstructive pulmonary disease

Background

Exacerbations of chronic obstructive pulmonary disease (COPD) are sporadic, acute worsening of symptoms. Identifying predictors of exacerbation frequency may facilitate medical interventions that reduce exacerbation frequency and severity. The objective of this study was to determine predictors of exacerbation frequency and mortality.

Methods

A total of 227 COPD patients were enrolled in a prospective clinical study between January 2000 and December 2011. Reported exacerbations were recorded for the year preceding enrollment and annually thereafter, and patients were grouped by median annual exacerbation frequency into those experiencing infrequent exacerbations (less than one exacerbation annually) and frequent exacerbations (one or more exacerbation annually). Patients experiencing frequent exacerbations were further divided into those experiencing moderately frequent exacerbations (fewer than two exacerbations per year) and severely frequent exacerbations (two or more exacerbations per year). The rate of clinical relapse and survival was recorded over a 10-year period. The mean of follow-up time was 5.15 years per patient.

Results

For patients experiencing infrequent, moderately frequent, and severely frequent exacerbations, median exacerbations in the year preceding enrollment were 0.0, 0.5, 1.0, respectively, and more frequent exacerbations correlated with lower baseline forced expiratory volume in one second (FEV₁) (0.81 L, 0.75 L, and 0.66 L, respectively), higher comorbidity (70.7%, 75.0%, and 89.4%, respectively), and greater NPPV use during hospitalization (16.4%, 35.9% and 51.1%, respectively). FEV₁ declined and mortality increased with increasing exacerbation frequency.

Conclusions

Exacerbation frequency can be used to generate discreet patient subpopulations, supporting the hypothesis that multiple COPD phenotypes exist and can be used in patient risk stratification.

Nonparametric tests of treatment effect based on combined endpoints for mortality and recurrent events

Terminal events are commonly combined with other outcomes to improve the power for detecting treatment effects in clinical studies. This manuscript explores novel ways to combine information on terminal and recurrent events in constructing two-sample tests. Existing approaches follow either a time-to-first event analysis approach or a recurrent event modeling approach. Nonparametric recurrent event analyses are often restricted by independence assumptions on gap times between events. Although time-to-first event analyses are not subject to this restriction, they discard information that occurs beyond the initial event and are much less powerful for detecting treatment differences. We develop two new approaches for determining treatment effects, motivated by less restrictive assumptions of time-to-first event analyses that combine information from multiple follow-up intervals. The first testing procedure pools (correlated) short-term τ -restricted outcomes from prespecified intervals starting at times t(k), k = 1, . . . , b, and compares estimated τ -restricted mean survival across treatment groups from this combined dataset. The second procedure calculates conditional τ-restricted means from those at risk at times t(k), k = 1, . . . , b, and compares the area under a function of these by treatment. Variances calculations, taking into account correlation of short-term outcomes within individuals, linearize random components of the test statistics following Woodruff (1971. A simple method for approximating the variance of a complicated estimate. Journal of the American Statistical Association 66, 411-414) and more recently Williams (1995. Product-limit survival functions with correlated survival times. Lifetime Data Analysis 1, 171-186). Simulations compare the finite sample performance of our tests to the robust proportional rates model proposed by Lin and others (2000. Semiparametric regression for the mean and rate functions of recurrent events. Journal of the Royal Statistical Society: Series B (Statistical Methodology) 62(4), 711-730) and the Ghosh and Lin (2000. Non-parametric analysis of recurrent events and death. Biometrics 56(2), 554-562) combined test for recurrent events and death. For different treatment effect patterns the proposed methods perform favorably when compared with existing methods. These new analysis approaches also produce correct type I error rates with correlated gap times between events. New methods are applied to data from a trial of azithromycin in patients with chronic obstructive pulmonary disease.

The Saudi Guidelines for the Diagnosis and Management of COPD

The Saudi Thoracic Society (STS) launched the Saudi Initiative for Chronic Airway Diseases (SICAD) to develop a guideline for the diagnosis and management of chronic obstructive pulmonary disease (COPD). This guideline is primarily aimed for internists and general practitioners. Though there is scanty epidemiological data related to COPD, the SICAD panel believes that COPD prevalence is increasing in Saudi Arabia due to increasing prevalence of tobacco smoking among men and women. To overcome the issue of underutilization of spirometry for diagnosing COPD, handheld spirometry is recommended to screen individuals at risk for COPD. A unique feature about this guideline is the simplified practical approach to classify COPD into three classes based on the symptoms as per COPD Assessment Test (CAT) and the risk of exacerbations and hospitalization. Those patients with low risk of exacerbation (<2 in the past year) can be classified as either Class I when they have less symptoms (CAT < 10) or Class II when they have more symptoms (CAT ≥ 10). High-risk COPD patients, as manifested with ≥2 exacerbation or hospitalization in the past year irrespective of the baseline symptoms, are classified as Class III. Class I and II patients require bronchodilators for symptom relief, while Class III patients are recommended to use medications that reduce the risks of exacerbations. The guideline recommends screening for co-morbidities and suggests a comprehensive management approach including pulmonary rehabilitation for those with a CAT score ≥10. The article also discusses the diagnosis and management of acute exacerbations in COPD.

Respiratory reviews in asthma 2013

From January 2012 up until March 2013, many articles with huge clinical importance in asthma were published based on large numbered clinical trials or meta-analysis. The main subjects of these studies were the new therapeutic plan based on the asthma phenotype or efficacy along with the safety issues regarding the current treatment guidelines. For efficacy and safety issues, inhaled corticosteroid tapering strategy or continued long-acting beta agonists use was the major concern. As new therapeutic trials, monoclonal antibodies or macrolide antibiotics based on inflammatory phenotypes have been under investigation, with promising preliminary results. There were other issues on the disease susceptibility or genetic background of asthma, particularly for the "severe asthma" phenotype. In the era of genome and pharmacogenetics, there have been extensive studies to identify susceptible candidate genes based on the results of genome wide association studies (GWAS). However, for severe asthma, which is where most of the mortality or medical costs develop, it is very unclear. Moreover, there have been some efforts to find important genetic information in order to predict the possible disease progression, but with few significant results up until now. In conclusion, there are new on-going aspects in the phenotypic classification of asthma and therapeutic strategy according to the phenotypic variations. With more pharmacogenomic information and clear identification of the "severe asthma" group even before disease progression from GWAS data, more adequate and individualized therapeutic strategy could be realized in the future.

Antitussive drugs--past, present, and future

Cough remains a serious unmet clinical problem, both as a symptom of a range of other conditions such as asthma, chronic obstructive pulmonary disease, gastroesophageal reflux, and as a problem in its own right in patients with chronic cough of unknown origin. This article reviews our current understanding of the pathogenesis of cough and the hypertussive state characterizing a number of diseases as well as reviewing the evidence for the different classes of antitussive drug currently in clinical use. For completeness, the review also discusses a number of major drug classes often clinically used to treat cough but that are not generally classified as antitussive drugs. We also reviewed a number of drug classes in various stages of development as antitussive drugs. Perhaps surprising for drugs used to treat such a common symptom, there is a paucity of well-controlled clinical studies documenting evidence for the use of many of the drug classes in use today, particularly those available over the counter. Nonetheless, there has been a considerable increase in our understanding of the cough reflex over the last decade that has led to a number of promising new targets for antitussive drugs being identified and thus giving some hope of new drugs being available in the not too distant future for the treatment of this often debilitating symptom.

Macrolides and mortality in critically ill patients with community-acquired pneumonia: a systematic review and meta-analysis

OBJECTIVE

Some studies suggest better outcomes with macrolide therapy for critically ill patients with community-acquired pneumonia. To further explore this, we performed a systematic review of studies with mortality endpoints that compared macrolide therapy with other regimens in critically ill patients with community-acquired pneumonia.

DATA SOURCES

Studies were identified via electronic databases, grey literature, and conference proceedings through May 2013.

STUDY SELECTION

Using prespecified criteria, two reviewers selected studies; studies of outpatients and hospitalized noncritically ill patients were excluded.

DATA EXTRACTION

Two reviewers extracted data and evaluated bias using the Newcastle-Ottawa Scale. Random effects models were used to generate pooled risk ratios and evaluate heterogeneity (I).

DATA SYNTHESIS

Twenty-eight observational studies (no randomized control trials) were included. Average age ranged from 58 to 78 years and 14-49% were women. In our primary analysis of 9,850 patients, macrolide use was associated with statistically significant lower mortality compared with nonmacrolides (21% [846 of 4,036 patients] vs 24% [1,369 of 5,814]; risk ratio, 0.82; 95% CI, 0.70-0.97; p = 0.02; I = 63%). When macrolide monotherapy was excluded, the macrolide mortality benefit was maintained (21% [737 of 3,447 patients] vs 23% [1,245 of 5,425]; risk ratio, 0.84; 95% CI, 0.71-1.00; p = 0.05; I = 60%). When broadly guideline-concordant regimens were compared, there was a trend to improved mortality and heterogeneity was reduced (20% [511 of 2,561 patients] mortality with beta-lactam/macrolide therapy vs 23% [386 of 1,680] with beta-lactam/fluoroquinolone; risk ratio, 0.83; 95% CI, 0.67-1.03; p = 0.09; I = 25%). When adjusted risk estimates were pooled from eight studies, macrolide therapy was still associated with a significant reduction in mortality (risk ratio, 0.75; 95% CI, 0.58-0.96; p = 0.02; I = 57%).

CONCLUSIONS

In observational studies of almost 10,000 critically ill patients with community-acquired pneumonia, macrolide use was associated with a significant 18% relative (3% absolute) reduction in mortality compared with nonmacrolide therapies. After pooling data from studies that provided adjusted risk estimates, an even larger mortality reduction was observed. These results suggest that macrolides be considered first-line combination treatment in critically ill patients with community-acquired pneumonia and support current guidelines.

[Long-term macrolide treatment in adult chronic bronchial diseases: benefits and limits]

Decreased frequency of pulmonary exacerbations, mainly related to immunomodulatory effects of macrolide antibiotics, has been demonstrated in bronchiectasis and chronic obstructive pulmonary diseases (COPD). Due to its tolerance, azithromycin is the antibiotic of choice for maintenance therapy at the dose of 250 mg per day or 500 mg × 3 per week (for body weight >55 kg). Maintenance therapy with macrolide could be proposed in selected patients with bronchiectasis or COPD with more than 3 acute exacerbations in the previous year or decreased lung function despite compliance with optimum treatment. The risk of sudden cardiac death with azithromycin is rare and controversial. It should be avoided in patients with a high baseline risk of cardiovascular disease, QT>450 msec, pulse rate>100 bpm and potential drug interactions, particularly those known to cause QT prolongation. It is recommended to search for hearing deficit (audiometry) and sputum culture positive for mycobacteria. Patients must also be aware that it can rapidly lead to macrolide resistance in commensal or pathogenic flora. Follow-up evaluation every 3 month can be proposed with medical history (hearing deficit) and electrocardiography. After one year, the treatment should be stopped in the absence of reduction in the frequency of exacerbations.

Long term streptomycin toxicity in the treatment of Buruli Ulcer: follow-up of participants in the BURULICO drug trial

BACKGROUND

Buruli Ulcer (BU) is a tropical infectious skin disease that is currently treated with 8 weeks of intramuscular streptomycin and oral rifampicin. As prolonged streptomycin administration can cause both oto- and nephrotoxicity, we evaluated its long term toxicity by following-up former BU patients that had received either 4 or 8 weeks of streptomycin in addition to other drugs between 2006 and 2008, in the context of a randomized controlled trial.

METHODS

Former patients were retrieved in 2012, and oto- and nephrotoxicity were determined by audiometry and serum creatinine levels. Data were compared with baseline and week 8 measurements during the drug trial.

RESULTS

Of the total of 151 former patients, 127 (84%) were retrieved. Ototoxicity was present in 29% of adults and 25% of children. Adults in the 8 week streptomycin group had significantly higher hearing thresholds in all frequencies at long term follow-up, and these differences were most prominent in the high frequencies. In children, no differences between the two treatment arms were found. Nephrotoxicity that had been detected in 14% of adults and in 13% of children during treatment, was present in only 2.4% of patients at long term follow-up.

CONCLUSIONS

Prolonged streptomycin administration in the adult study subjects caused significant persistent hearing loss, especially in the high frequency range. Nephrotoxicity was also present in both adults and children but appeared to be transient. Streptomycin should be given with caution especially in patients aged 16 or older, and in individuals with concurrent risks for renal dysfunction or hearing loss.

Azithromycin: mechanisms of action and their relevance for clinical applications

Azithromycin is a macrolide antibiotic which inhibits bacterial protein synthesis, quorum-sensing and reduces the formation of biofilm. Accumulating effectively in cells, particularly phagocytes, it is delivered in high concentrations to sites of infection, as reflected in rapid plasma clearance and extensive tissue distribution. Azithromycin is indicated for respiratory, urogenital, dermal and other bacterial infections, and exerts immunomodulatory effects in chronic inflammatory disorders, including diffuse panbronchiolitis, post-transplant bronchiolitis and rosacea. Modulation of host responses facilitates its long-term therapeutic benefit in cystic fibrosis, non-cystic fibrosis bronchiectasis, exacerbations of chronic obstructive pulmonary disease (COPD) and non-eosinophilic asthma. Initial, stimulatory effects of azithromycin on immune and epithelial cells, involving interactions with phospholipids and Erk1/2, are followed by later modulation of transcription factors AP-1, NFκB, inflammatory cytokine and mucin release. Delayed inhibitory effects on cell function and high lysosomal accumulation accompany disruption of protein and intracellular lipid transport, regulation of surface receptor expression, of macrophage phenotype and autophagy. These later changes underlie many immunomodulatory effects of azithromycin, contributing to resolution of acute infections and reduction of exacerbations in chronic airway diseases. A sub-group of post-transplant bronchiolitis patients appears to be sensitive to azithromycin, as may be patients with severe sepsis. Other promising indications include chronic prostatitis and periodontitis, but weak activity in malaria is unlikely to prove crucial. Long-term administration of azithromycin must be balanced against the potential for increased bacterial resistance. Azithromycin has a very good record of safety, but recent reports indicate rare cases of cardiac torsades des pointes in patients at risk.

Acute Exacerbation and Respiratory InfectionS in COPD (AERIS): protocol for a prospective, observational cohort study

INTRODUCTION

The aetiology of acute exacerbations of chronic obstructive pulmonary disease (COPD) remains incompletely understood and strategies for treatment and prevention have not altered significantly for many years. Improved understanding of the role of respiratory pathogens in acute exacerbations of COPD (AECOPD) is required and the use of molecular microbiological techniques may lead to insights into host-pathogen interactions and the development of more targeted therapeutic approaches.

METHODS AND ANALYSES

Acute Exacerbation and Respiratory InfectionS in COPD (AERIS) is a longitudinal epidemiological study to assess how changes in the COPD airway microbiome contribute to the incidence and severity of AECOPD. Patients with COPD aged 40-85 are followed monthly for 2 years, and reviewed within 72 h of onset of symptoms of AECOPD. Exacerbations are detected using daily electronic diary cards. Blood, sputum, nasopharyngeal and urine samples are collected at prespecified timepoints. Molecular diagnostic and typing techniques are used to describe the dynamics of airway infection during AECOPD and stable disease, and associations with clinical outcome. This study aims to refine the case definition of AECOPD to reflect the possible microbiological aetiology. AERIS will assess the impact of AECOPD on health-related quality of life and healthcare resource utilisation, and the possible interactions between nutritional status, infection and immune responses.

ETHICS AND DISSEMINATION

AERIS is conducted in accordance with the Declaration of Helsinki and Good Clinical Practice, and has been approved by the institutional ethics and review board. All participants must provide written informed consent. The results obtained will be disseminated at international medical conferences and in peer-reviewed publications.

DISCUSSION

Few other studies have addressed the complexity of the microbiological and systemic components of COPD or employed real-time electronic tracking of symptoms to identify AECOPD and potential aetiological triggers.

RESULTS

Results of AERIS will increase our understanding of the contribution of pathogens to AECOPD, potentially leading to new targeted therapeutic and preventative interventions.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov NCT01360398.

Efficacy and safety of long-term antibiotics (macrolides) for the treatment of chronic rhinosinusitis

Long-term treatment of airway inflammation/infection with macrolide antibiotics has now been in use for almost 30 years. Whereas the beneficial clinical effect in cystic fibrosis and COPD have been backed up by randomized controlled trials, the evidence from the upper airways is not as strong. We have identified 22 open studies in chronic rhinosinusitis, with and without polyps, but only 2 randomized controlled trials. Of the controlled trials, the one including CRS patients just without polyps, showed a significant effect in sino-nasal outcome test, saccharine transit time, nasal endoscopy, and IL-8 levels in lavage fluid after 12 weeks of roxithromycin, whereas, in the other RCT with a mixed study group of CRS patients with and without polyps, 12 weeks of azithromycin showed no effect compared to placebo. Concerns regarding the risk of macrolides to induce arrhythmia have been raised. Recent FDA guidelines changes has recommended caution in patients with risk factors such as long QT syndrome, bradycardia, hypokalemia, or hypomagnesemia. Ototoxicity is another concern. Long-term macrolide antibiotics in the treatment of CRS patients is still a viable option in a select group of patients.

Population pharmacokinetics of azithromycin in whole blood, peripheral blood mononuclear cells, and polymorphonuclear cells in healthy adults

Azithromycin's extensive distribution to proinflammatory cells, including peripheral blood mononuclear cells (PBMCs) and polymorphonuclear cells (PMNs), may be important to its antimicrobial and anti-inflammatory properties. The need to simultaneously predict azithromycin concentrations in whole blood ("blood"), PBMCs, and PMNs motivated this investigation. A single-dose study in 20 healthy adults was conducted, and nonlinear mixed effects modeling was used to simultaneously describe azithromycin concentrations in blood, PBMCs, and PMNs (simultaneous PK model). Data were well described by a four-compartment mamillary model. Apparent central clearance and volume of distribution estimates were 67.3 l/hour and 336 l (interindividual variability of 114 and 122%, respectively). Bootstrapping and visual predictive checks showed adequate model performance. Azithromycin concentrations in blood, PBMCs, and PMNs from external studies of healthy adults and cystic fibrosis patients were within the 5th and 95th percentiles of model simulations. This novel empirical model can be used to predict azithromycin concentrations in blood, PBMCs, and PMNs with different dosing regimens.

Community-based recruitment of patients with COPD into clinical research

Abstract

Identifying subjects for clinical trials is difficult and the evidence base for recruitment strategies is limited, particularly in the field of COPD. We compared the efficiency and patient characteristics of different community-based recruitment strategies during a non-commercial COPD trial in the UK. Recruiting from general practice COPD registers was less efficient and identified patients with significantly milder disease than recruiting through pulmonary rehabilitation and patient groups. We report our experience and propose that pulmonary rehabilitation and patient groups may represent an enriched pool of COPD patients to recruit into clinical trials.

Trial registration number:

EudraCT 2011-001063-43

Chronic obstructive pulmonary disease (COPD): evaluation from clinical, immunological and bacterial pathogenesis perspectives

Chronic obstructive pulmonary disease (COPD), a disease manifested by significantly impaired airflow, afflicts ∼14.2 million cases in the United States alone with an estimated 63 million people world-wide. Although there are a number of causes, the predominant cause is excessive tobacco smoke. In fact, in China, there have been estimates of 315,000,000 people that smoke. Other less frequent causes are associated with indirect cigarette smoke, air pollutants, biomass fuels, and genetic mutations. COPD is often associated with heart disease, lung cancer, osteoporosis and conditions can worsen in patients with sudden falls. COPD also affects both innate and adaptive immune processes. Cigarette smoke increases the expression of matrix metalloproteases and proinflammatory chemokines and increases lung titers of natural killer cells and neutrophils. Yet, neutrophil reactive oxygen species (ROS) mediated by the phagocytic respiratory burst and phagocytosis is impaired by nicotine. In contrast to innate immunity in COPD, dendritic cells represent leukocytes recruited to the lung that link the innate immune responses to adaptive immune responses by activating naïve T cells through antigen presentation. The autoimmune process that is also a significant part of inflammation associated with COPD. Moreover, coupled with restricted FEV1 values, are the prevalence of patients with single or multiple infections by bacteria, viruses and fungi. Finally, we focus on one of the more problematic infectious agents, the Gram-negative opportunistic pathogenic bacterium, Pseudomonas aeruginosa. Specifically, we delve into the development of highly problematic biofilm infections that are highly refractory to conventional antibiotic therapies in COPD. We offer a non-conventional, biocidal treatment that may be effective for COPD airway infections as well as with combinations of current antibiotic regimens for more effective treatment outcomes and relief for patients with COPD.

Introducing the COPD Foundation Guide for Diagnosis and Management of COPD, recommendations of the COPD Foundation

The increasing number of treatment options for managing patients with chronic obstructive pulmonary disease (COPD) promises to improve the outcomes for COPD patients. However, determining which treatments are appropriate for individual patients has become increasingly complex. The COPD Foundation Guide for Diagnosis and Management of COPD was developed to be a practical, easy to use tool for clinicians. The Guide includes specific recommendations for diagnostic studies and treatments based on specific diagnostic criteria. This manuscript describes the rationale for the development of the Guide, the process used, the rationale for the specific recommendations and the plans for further development. The current recommendations of the COPD Foundation have been summarized in the form of Pocket Cards, which may be obtained from the Foundation at no charge (1-866-316-COPD (2673), www.copdfoundation.org).

Bacterial microbiome of lungs in COPD

Chronic obstructive pulmonary disease (COPD) is currently the third leading cause of death in the world. Although smoking is the main risk factor for this disease, only a minority of smokers develop COPD. Why this happens is largely unknown. Recent discoveries by the human microbiome project have shed new light on the importance and richness of the bacterial microbiota at different body sites in human beings. The microbiota plays a particularly important role in the development and functional integrity of the immune system. Shifts or perturbations in the microbiota can lead to disease. COPD is in part mediated by dysregulated immune responses to cigarette smoke and other environmental insults. Although traditionally the lung has been viewed as a sterile organ, by using highly sensitive genomic techniques, recent reports have identified diverse bacterial communities in the human lung that may change in COPD. This review summarizes the current knowledge concerning the lung microbiota in COPD and its potential implications for pathogenesis of the disease.

Impact of heterozygote CFTR mutations in COPD patients with chronic bronchitis

Background

Cigarette smoking causes Chronic Obstructive Pulmonary Disease (COPD), the 3rd leading cause of death in the U.S. CFTR ion transport dysfunction has been implicated in COPD pathogenesis, and is associated with chronic bronchitis. However, susceptibility to smoke induced lung injury is variable and the underlying genetic contributors remain unclear. We hypothesized that presence of CFTR mutation heterozygosity may alter susceptibility to cigarette smoke induced CFTR dysfunction. Consequently, COPD patients with chronic bronchitis may have a higher rate of CFTR mutations compared to the general population.

Methods

Primary human bronchial epithelial cells derived from F508del CFTR heterozygotes and mice with (CFTR+/-) and without (CFTR+/+) CFTR heterozygosity were exposed to whole cigarette smoke (WCS); CFTR-dependent ion transport was assessed by Ussing chamber electrophysiology and nasal potential difference measurements, respectively. Caucasians with COPD and chronic bronchitis, age 40 to 80 with FEV₁/FVC < 0.70 and FEV₁ < 60% predicted, were selected for genetic analysis from participants in the NIH COPD Clinical Research Network’s Azithromycin for Prevention of Exacerbations of COPD in comparison to 32,900 Caucasian women who underwent prenatal genetic testing. Genetic analysis involved an allele-specific genotyping of 89 CFTR mutations.

Results

Exposure to WCS caused a pronounced reduction in CFTR activity in both CFTR (+/+) cells and F508del CFTR (+/-) cells; however, neither the degree of decrement (44.7% wild-type vs. 53.5% F508del heterozygous, P = NS) nor the residual CFTR activity were altered by CFTR heterozygosity. Similarly, WCS caused a marked reduction in CFTR activity measured by NPD in both wild type and CFTR heterozygous mice, but the severity of decrement (91.1% wild type vs. 47.7% CF heterozygous, P = NS) and the residual activity were not significantly affected by CFTR genetic status. Five of 127 (3.9%) COPD patients with chronic bronchitis were heterozygous for CFTR mutations which was not significantly different from controls (4.5%) (P = NS).

Conclusions

The magnitude of WCS induced reductions in CFTR activity was not affected by the presence of CFTR mutation heterozygosity. CFTR mutations do not increase the risk of COPD with chronic bronchitis. CFTR dysfunction due to smoking is primarily an acquired phenomenon and is not affected by the presence of congenital CFTR mutations.