Systemic manifestations and comorbidities of COPD

Relationship between osteoporosis and adipose tissue leptin and osteoprotegerin in patients with chronic obstructive pulmonary disease

INTRODUCTION

The role of fat-bone interactions in the pathogenesis of osteoporosis in chronic obstructive pulmonary disease (COPD) is poorly understood. Our aim was to investigate expressions of leptin and osteoprotegerin (OPG) in the adipose tissue, and their relationships to osteoporosis in patients with COPD.

METHODS

In 39 patients with stable COPD, bone mineral density (BMD) and body composition was assessed by Dual Energy X-Ray Absorptiometry. Serum leptin was determined by the enzyme-linked immunosorbent assay, and bone turnover markers osteocalcin and β-crosslaps by the electrochemiluminiscence immunoassays. Subcutaneous adipose tissue samples were analyzed using real-time PCR.

RESULTS

Twenty-one patients without, and 18 with osteoporosis were enrolled (35 men; age 62.2 ± 7.3years). Compared to patients without osteoporosis, those with the disease had significantly lower serum levels and adipose tissue expressions of leptin, in association with increased serum β-crosslaps (p=0.028, p=0.034, p=0.022, respectively). Log adipose tissue leptin was inversely related to serum β-crosslaps (p=0.015), and directly to serum leptin (p<0.001) and to the total, femoral, and lumbar BMD and T-score (p<0.02 for all relationships). Adipose tissue OPG expression was related to all variables of bone density except for lumbar BMD and T-score (p<0.05 for all relationships). Log adipose tissue leptin and OPG expressions predicted femoral T-score independently of age, gender and pulmonary function (p<0.001, adjusted R(2)=0.383; p=0.008, adjusted R(2)=0.301, respectively). Introducing body mass (or fat mass) index into these models eliminated independent predictive value of leptin and OPG expressions.

CONCLUSION

Our results suggest that adipose tissue leptin and OPG expressions are related to osteoporosis in patients with COPD, and appear to act as mediators between fat mass and BMD.

Systemic manifestations of COPD

COPD is characterized by a poorly reversible airflow limitation resulting from chronic inflammation, mainly due to tobacco exposure. Over the past few years, the understanding of COPD has evolved from it being a disease affecting the lungs to it being a complex, heterogeneous, and generalized disorder in an aging population. Extrapulmonary comorbidities significantly complicate the management and influence the prognosis of patients with COPD. Although certain comorbidities like cardiovascular diseases share some risk factors with COPD, such as cigarette smoking, other frequently observed comorbidities, including musculoskeletal wasting, metabolic syndrome, and depression, cannot be easily attributed to smoking. There is increasing evidence that chronic inflammation is a key factor in COPD and that inflammation might be the common pathway linking these comorbidities and explaining why they typically develop together. Physicians treating patients with COPD need to become aware of these extrapulmonary aspects. Any patient with COPD should be carefully evaluated for comorbidities and the systemic consequences of COPD since they not only influence the prognosis but also have an impact on disease management. The treatment of COPD is no longer focused exclusively on inhaled therapy but is taking on a multidimensional approach, especially because the treatment of the comorbidities might positively affect the course of COPD itself.

Anaemia in chronic respiratory failure

BACKGROUND

In patients with severe chronic obstructive pulmonary disease (COPD), anaemia is common and associated with impaired long-term survival and quality of life. Whether anaemia is also prevalent in patients with other severe, non-inflammatory respiratory diseases has not yet been systematically tested.

METHODS

In 595 patients with obstructive (OD, 54.8%) or restrictive disease (RD, 45.2%) and chronic respiratory failure (CRF), anthropometric data, laboratory parameters, lung function, blood gases and comorbidities were assessed prior to initiation of home mechanical ventilation. Patients were classified as anaemic based on haemoglobin (Hb) levels (Hb<12/13 g/dl, female patients/male patients). Patients with known causes for anaemia were excluded.

RESULTS

In patients with CRF the prevalence of anaemia was 13.3% and not different between RD (11.5%) and OD (14.7%) (p=0.276). A sex-related difference occurred only in OD [7.9% (f) vs. 17.3% (m); p=0.035]. Patients with OD and anaemia presented with higher age (p=0.003), pH (p=0.014) and arterial oxygen pressure (PaO(2) ) (p=0.012), lower body mass index (BMI) (p=0.011) and total protein (p=0.012) and higher rates of coronary heart disease (p=0.01), cardiac arrhythmia (p=0.014) and diabetes mellitus (p=0.003) in comparison to non-anaemic patients. In patients with RD anaemia was associated with higher age, (p=0.008), pH (p=0.011) and lower leucocytes numbers (p=0.006).

CONCLUSIONS

Anaemia is frequent not only in COPD but also in other severe respiratory diseases combined with CRF. It was associated with advanced age, several comorbidities, impaired nutritional state and elevations of pH and PaO(2) , probably because of hyperventilation. Its prognostic impact has to be elucidated in future studies.

COPD: a multifactorial systemic disease

Chronic obstructive pulmonary disease (COPD) has traditionally been considered a disease of the lungs secondary to cigarette smoking and characterized by airflow obstruction due to abnormalities of both airway (bronchitis) and lung parenchyma (emphysema). It is now well known that COPD is associated with significant systemic abnormalities, such as renal and hormonal abnormalities, malnutrition, muscle wasting, osteoporosis, and anemia. However, it is still unclear whether they represent consequences of the pulmonary disorder, or whether COPD should be considered as a systemic disease. These systemic abnormalities have been attributed to an increased level of systemic inflammation. Chronic inflammation, however, may not be the only cause of the systemic effects of COPD. Recent data from humans and animal models support the view that emphysema may be a vascular disease. Other studies have highlighted the role of repair failure, bone marrow abnormality, genetic and epigenetic factors, immunological disorders and infections as potential causes of COPD systemic manifestations. Based on this new evidence, it is reasonable to consider COPD, and emphysema in particular, as 'a disease with a significant systemic component' if not a 'systemic disease' per se. The aim of this review is to give an overview of the most relevant and innovative hypothesis about the extrapulmonary manifestations of COPD.

Role of CA-125 in identification of right ventricular failure in chronic obstructive pulmonary disease

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a progressive and debilitating disease. Cor pulmonale, characterized by right ventricular (RV) failure, can severely influence prognosis in these patients. Hence, early recognition might be important for tailoring therapy. An old biomarker, CA-125, seems to be associated with the right heart. We aimed to show the relationship between CA-125 levels and RV failure in patients with COPD.

HYPOTHESIS

CA-125 might be a useful biomarker in identification of RV failure in patients with COPD.

METHODS

Forty patients with recent exacerbation of COPD were enrolled into the study. Another 40 age- and sex-matched individuals were enrolled for comparison. Levels of CA-125 were measured in the patients during the hospital stay. The COPD patients underwent echocardiographic study on the same day. Right-ventricular parameters were evaluated, and RV failure was identified via transthoracic echocardiography.

RESULTS

Patients with COPD had significantly higher CA-125 levels compared with controls (median 33.94 U/mL vs 9.76 U/mL, respectively; P < 0.001). Levels of CA-125 were correlated with systolic pulmonary artery pressure (r = 0.550, P < 0.001), tricuspid annular plane systolic excursion (r = - 0.496, P = 0.001), and tricuspid lateral annulus S velocity (r = - 0.549, P = 0.002). High CA-125 levels, obtained in hospitalized patients with COPD before echocardiography, enabled identification of RV failure with a sensitivity of 89.5% and specificity of 85.7%.

CONCLUSIONS

The CA-125 biomarker can be used to identify COPD patients with RV failure.

Mortality in COPD: causes, risk factors, and prevention

Chronic obstructive pulmonary disease (COPD) is a leading and increasing cause of death, the extent of which is underestimated as a consequence of underdiagnosis and underreporting on death certificates. Data from large trials, such as the Lung Health Study, Towards a Revolution in COPD Health (TORCH), Understanding Potential Long-term Impacts on Function with Tiotropium (UPLIFT), European Respiratory Society Study on Chronic Obstructive Pulmonary Disease (EUROSCOP), and Inhaled Steroids in Obstructive Lung Disease (ISOLDE), have shown that the causes of death in patients with mild COPD are predominantly cancer and cardiovascular disease, but as COPD severity increases, deaths due to non-malignant respiratory disease are increasingly common. In practice, mortality of patients with COPD can be predicted by a variety of measures including: forced expiratory volume in one second (FEV(1)), the ratio of inspiratory and total lung capacities, exercise capacity, dyspnea scores, and composite indices such as the body-mass index (B), degree of airflow obstruction (O), degree of functional dyspnea (D), and exercise capacity (E) (BODE) index. Smoking cessation improves survival in COPD patients, and in select patients with advanced disease, oxygen therapy, lung volume reduction surgery, or lung transplantation may also improve survival.

Macrolide antibiotics broadly and distinctively inhibit cytokine and chemokine production by COPD sputum cells in vitro

Macrolide antibiotics are known to exert anti-inflammatory actions in vivo, including certain effects in COPD patients. In order to investigate the immunomodulatory profile of activity of macrolide antibiotics, we have studied the effects of azithromycin, clarithromycin, erythromycin and roxithromycin on the in vitro production of a panel of inflammatory mediators from cells isolated from human, steroid-naïve, COPD sputum samples. Macrolide effects were compared to three other commonly used anti-inflammatory compounds, the corticosteroid dexamethasone, the PDE4 inhibitor, roflumilast and the p38 kinase inhibitor, SB203580. Three of the four tested macrolides, azithromycin, clarithromycin and roxithromycin, exhibited pronounced, concentration-related reduction of IL-1β, IL-6, IL-10, TNF-α, CCL3, CCL5, CCL20, CCL22, CXCL1, CXCL5, and G-CSF release. Further slight inhibitory effects on IL-1α, CXCL8, GM-CSF, and PAI-1 production were also observed. Erythromycin was very weakly active. Qualitatively and quantitatively, macrolides exerted distinctive and, compared to other tested classes of compounds, more pronounced immunomodulatory effects, particularly in terms of chemokine (CCL3, CCL5, CCL20, CCL22, and CXCL5), IL-1β, G-CSF and PAI-1 release. The described modulation of inflammatory mediators could potentially contribute to further definition of biomarkers of macrolide anti-inflammatory activity in COPD.

Hemoglobin, erythropoietin and systemic inflammation in exacerbations of chronic obstructive pulmonary disease

BACKGROUND

Systemic inflammation may represent a possible cause of anemia. Previous data support that anemic patients with COPD present high erythropoietin (EPO) levels, suggestive of EPO resistance, possibly mediated through inflammatory mechanisms.

OBJECTIVES

We aimed to determine whether systemic inflammation, which is usually up-regulated during exacerbations of COPD (ECOPD) is associated with low hemoglobin levels expressing erythropoietin resistance.

METHODS

Hemoglobin (Hb), EPO and serum biomarkers of systemic inflammation [CRP, TNF-α, fibrinogen and IL-6] were assessed at three time points (admission, resolution and stable phases) in a selected cohort of 93 COPD patients.

RESULTS

Hemoglobin levels were significantly lower on admission compared to resolution and stable phases (median 12.1 g/dl [interquartile ranges 11.2-12.7], vs 13.5 [12.4-14.3] vs 13.4 [12.7-14.08], respectively p=0.002), whereas EPO was significantly higher on admission compared to resolution and stable phases. A negative association between Hb and IL-6 and a positive association between EPO and IL-6 were observed only during the acute phase of exacerbation. EPO and Hb were negatively associated during the acute phase, whereas they were positively associated during discharge and stable phase.

CONCLUSIONS

In this observational study we have shown that during admission for ECOPD Hb levels are decreased and EPO levels are increased. We have also identified a negative association between Hb and EPO. The above association is mainly related to increased IL-6 levels, indicating a possible EPO resistance through the mechanism of increased systemic inflammatory process.

Physical activity is the strongest predictor of all-cause mortality in patients with COPD: a prospective cohort study

BACKGROUND

Systemic effects of COPD are incompletely reflected by established prognostic assessments. We determined the prognostic value of objectively measured physical activity in comparison with established predictors of mortality and evaluated the prognostic value of noninvasive assessments of cardiovascular status, biomarkers of systemic inflammation, and adipokines.

METHODS

In a prospective cohort study of 170 outpatients with stable COPD (mean FEV(1), 56% predicted), we assessed lung function by spirometry and body plethysmography; physical activity level (PAL) by a multisensory armband; exercise capacity by 6-min walk distance test; cardiovascular status by echocardiography, vascular Doppler sonography (ankle-brachial index [ABI]), and N-terminal pro-B-type natriuretic peptide level; nutritional and muscular status by BMI and fat-free mass index; biomarkers by levels of high-sensitivity C-reactive protein, IL-6, fibrinogen, adiponectin, and leptin; and health status, dyspnea, and depressive symptoms by questionnaire. Established prognostic indices were calculated. The median follow-up was 48 months (range, 10-53 months).

RESULTS

All-cause mortality was 15.4%. After adjustments, each 0.14 increase in PAL was associated with a lower risk of death (hazard ratio [HR], 0.46; 95% CI, 0.33-0.64; P < .001). Compared with established predictors, PAL showed the best discriminative properties for 4-year survival (C statistic, 0.81) and was associated with the highest relative risk of death per standardized decrease. Novel predictors of mortality were adiponectin level (HR, 1.34; 95% CI, 1.06-1.71; P = .017), leptin level (HR, 0.81; 95% CI, 0.65-0.99; P = .042), right ventricular function (Tei-index) (HR, 1.26; 95% CI, 1.04-1.54; P = .020), and ABI < 1.00 (HR, 3.87; 95% CI, 1.44-10.40; P = .007). A stepwise Cox regression revealed that the best model of independent predictors was PAL, adiponectin level, and ABI. The composite of these factors further improved the discriminative properties (C statistic, 0.85).

CONCLUSIONS

We found that objectively measured physical activity is the strongest predictor of all-cause mortality in patients with COPD. In addition, adiponectin level and vascular status provide independent prognostic information in our cohort.

Biomarkers of systemic inflammation and depression and fatigue in moderate clinically stable COPD

INTRODUCTION

COPD is an inflammatory disease with major co-morbidities. It has recently been suggested that depression may be the result of systemic inflammation. We aimed to explore the association between systemic inflammation and symptoms of depression and fatigue in patients with mainly moderate and clinically stable COPD using a range of inflammatory biomarkers, 2 depression and 2 fatigue scales.

METHOD

We assessed 120 patients with moderate COPD (FEV1% 52, men 62%, age 66). Depression was assessed using the BASDEC and CES-D scales. Fatigue was assessed using the Manchester COPD-fatigue scale (MCFS) and the Borg scale before and after 6MWT. We measured systemic TNF-α, CRP, TNF-α-R1, TNF-α-R2 and IL-6.

RESULTS

A multivariate linear model of all biomarkers showed that TNF-α only had a positive correlation with BASDEC depression score (p = 0.007). TNF-α remained positively correlated with depression (p = 0.024) after further adjusting for TNF-α-R1, TNF-α-R2, 6MWD, FEV1%, and pack-years. Even after adding the MCFS score, body mass and body composition to the model TNF-α was still associated with the BASDEC score (p = 0.044). Furthermore, patients with higher TNF-α level (> 3 pg/ml, n = 7) had higher mean CES-D depression score than the rest of the sample (p = 0.03). Borg fatigue score at baseline were weakly correlated with TNF-α and CRP, and with TNF-α only after 6MWT. Patients with higher TNF-α had more fatigue after 6MWD (p = 0.054).

CONCLUSION

This study indicates a possible association between TNF-α and two frequent and major co-morbidities in COPD; i.e., depression and fatigue.

Pharmacology, clinical efficacy, and tolerability of phosphodiesterase-4 inhibitors: impact of human pharmacokinetics

Since more than two decades anti-inflammatory effects of inhibitors of phosphodiesterase-4 have been described in numerous cellular and animal studies and were finally confirmed in clinical trials. The path from an early, pioneering study with Ro20-1724 showing reduction of psoriatric plaque size in 1979 to modern PDE4 inhibitors such as oral apremilast in development for psoriasis, the inhaled PDE4 inhibitor GSK256066 in development for asthma and COPD and finally roflumilast, the first PDE4 inhibitor approved and currently marketed as an oral, once-daily remedy for severe COPD was marked by large progress in chemical optimization based on improved understanding of PDE4 biology and drug-like properties determining the appropriate pharmacokinetic profile. In this chapter aspects of the pharmacology and clinical efficacy of PDE4 inhibitors, which have been in clinical development over the years are summarized with specific emphasis on their clinical pharmacokinetic properties.

Metabolic phenotype and adipose tissue inflammation in patients with chronic obstructive pulmonary disease

Potential links between metabolic derangements and adipose tissue (AT) inflammation in patients with chronic obstructive pulmonary disease (COPD) are unexplored. We investigated AT expressions of interleukin (IL)-6, tumor necrosis factor (TNF)-α, CD68 (macrophage cell surface receptor), caspase-3, and Bax, and their relationships to the metabolic phenotype in nine cachectic, 12 normal-weight, 12 overweight, and 11 obese patients with COPD (age 62.3 ± 7.2 years). With increasing body mass index, increases in AT expressions of IL-6, TNF-α, and CD68 were observed (P < .001; P = .005; P < .001, resp.), in association with reduced insulin sensitivity (P < .001). No differences were observed between cachectic and normal-weight patients in AT expressions of inflammatory or proapoptotic markers. Adipose tissue CD68 and TNF-α expressions predicted insulin sensitivity independently of known confounders (P = .005; P = .025; R² = 0.840). Our results suggest that AT inflammation in obese COPD patients relates to insulin resistance. Cachectic patients remain insulin sensitive, with no AT upregulation of inflammatory or proapoptotic markers.

Cardiovascular and musculskeletal co-morbidities in patients with alpha 1 antitrypsin deficiency

Background

Determining the presence and extent of co-morbidities is fundamental in assessing patients with chronic respiratory disease, where increased cardiovascular risk, presence of osteoporosis and low muscle mass have been recognised in several disease states. We hypothesised that the systemic consequences are evident in a further group of subjects with COPD due to Alpha-1 Antitrypsin Deficiency (A1ATD), yet are currently under-recognised.

Methods

We studied 19 patients with PiZZ A1ATD COPD and 20 age, sex and smoking matched controls, all subjects free from known cardiovascular disease. They underwent spirometry, haemodynamic measurements including aortic pulse wave velocity (aPWV), an independent predictor or cardiovascular risk, dual energy X-ray absorptiometry to determine body composition and bone mineral density.

Results

The aPWV was greater in patients: 9.9(2.1) m/s than controls: 8.5(1.6) m/s, p = 0.03, despite similar mean arterial pressure (MAP). The strongest predictors of aPWV were age, FEV₁% predicted and MAP (all p < 0.01). Osteoporosis was present in 8/19 patients (2/20 controls) and was previously unsuspected in 7 patients. The fat free mass and bone mineral density were lower in patients than controls (p < 0.001).

Conclusions

Patients with A1ATD related COPD have increased aortic stiffness suggesting increased risk of cardiovascular disease and evidence of occult musculoskeletal changes, all likely to contribute hugely to overall morbidity and mortality.

Usefulness of mid regional pro-atrial natriuretic peptide in the exacerbations of chronic obstructive pulmonary disease

BACKGROUND

A recent approach for the management of chronic obstructive pulmonary disease (COPD) is the measurement of systemic biomarkers. The aim of this study was to evaluate the usefulness of mid regional pro-atrial natriuretic peptide (MR-proANP) to predict short and long term prognosis.

METHODS

We included 318 COPD patients: 46 in a stable phase, 217 undergoing an exacerbation and 55 with pneumonia. Serum samples were collected at admission. For 20 exacerbated patients, we also collected a second sample one month later. MR-proANP was measured by an inmunofluorescent assay.

RESULTS

Statistically higher levels of MR-proANP were found in patients with pneumonia when comparing to patients in the stable state (p=0.031). For those patients with paired samples, MR-proANP decreased statistically one month later (p=0.027). MR-proANP showed significant lower levels in exacerbations with isolation of pathogenic bacteria (p=0.011). MR-proANP levels were higher in patients that died within one month, decreasing as long as the moment of death occurred later on (p=0.163).

CONCLUSIONS

The identification of exacerbation etiology by means of MR-proANP is not clinically reliable. Levels of MR-proANP vary depending on the clinical status, being higher during pneumonia in comparison to the stable state. MR-proANP levels were higher in patients that died within one month after the exacerbation episode.

Moving towards a new generation of animal models for asthma and COPD with improved clinical relevance

Asthma and chronic obstructive pulmonary disease (COPD) are complex inflammatory airway diseases characterised by airflow obstruction that remain leading causes of hospitalization and death worldwide. Animal modelling systems that accurately reflect disease pathophysiology continue to be essential to the development of new therapies for both conditions. In this review, we describe preclinical in vivo models that recapitulate many of the features of asthma and COPD. Specifically, we discuss the pro's and con's of the standard models and highlight recently developed systems designed to more accurately reflect the complexity of both diseases. For instance, clinically relevant allergens (i.e. house dust mite) are now being used to mimic the inflammatory changes and airway remodelling that result after chronic allergen exposures. Additionally, systems are being developed to mimic steroid-resistant and viral exacerbations of allergic inflammation - aspects of asthma where there is an acute need for new therapies. Similarly, COPD models have evolved to align with the improved clinical understanding of the factors contributing to disease progression. This includes using cigarette smoke to model not only airway inflammation and remodelling, but some systemic changes (e.g. hypertension and skeletal muscle alterations) that are thought to influence disease. Further, mouse genetics are being exploited to gain insights into the genetics of COPD susceptibility. The new models of asthma and COPD described herein demonstrate that improved clinical understanding of the diseases and better preclinical models is an iterative process that will hopefully lead to therapies that can effectively manage severe asthma and COPD.

Association of serotonin transporter gene variation with smoking, chronic obstructive pulmonary disease, and its depressive symptoms

A serotonin transporter gene, SLC6A4, is thought to be related to nicotine dependence and depression, one of the comorbidities of chronic obstructive pulmonary disease (COPD). To investigate the association between SLC6A4 variation and tobacco consumption, susceptibility to COPD, and depression status. In all, 247 patients with COPD and 119 control subjects were genotyped for 5 tag single-nucleotide polymorphisms (SNPs) of SLC6A4. We analyzed the correlation between these genotypes and COPD, using the results of a pulmonary function test or chest computed tomography; data on tobacco consumption (pack-years); and the depression score based on the hospital anxiety and depression scale (HADS) after adjusting for age, gender, and smoking status (and pack-years, when appropriate). The rare allele rs2020936 was significantly associated with COPD incidence in the trend model (P = 0.003; odds ratio, 2.20; 95% confidence interval, 1.31-3.74). This allele was also associated with the number of pack-years (P = 0.026). The major allele of another SNP of SLC6A4, namely rs3794808, correlated with the HADS depression score (P = 0.016). We conclude that SLC6A4 variation affects COPD pathogenesis, and this effect depends partly on tobacco consumption. SLC6A4 variation also affects depressive symptoms. SLC6A4 could be modified to prevent COPD and treat the depressive symptoms of COPD.

Short-term effects of inhalative tiotropium/formoterol/budenoside versus tiotropium/formoterol in patients with newly diagnosed chronic obstructive pulmonary disease requiring surgery for lung cancer: a prospective randomized trial

OBJECTIVE

A new diagnosis of chronic obstructive pulmonary disease (COPD) is often made during the evaluation of patients requiring a surgical intervention for lung cancer. Based on initial impaired lung function, these untreated patients are often considered not fit for lung surgery. There is limited information on the short-term effectiveness of preoperative pharmacologic treatment strategies in patients with newly diagnosed COPD before lung surgery.

METHODS

A prospective randomized study was conducted comparing 1-week-treatment periods of tiotropium/formoterol/budenoside (GR1) with tiotropium/formoterol (GR2) in conjunction with smoking cessation and chest physiotherapy. No patients had been previously treated for COPD. The primary end point was body plethysmography (forced expiratory volume in 1s (FEV1), forced vital capacity (FVC), and airway resistance (RAW)) at the end of each treatment period. Secondary end points were improvement of ≥ 10% in FEV1 (% predicted) and improvement of the severity of COPD after the 1-week treatment, as well as the rate of pulmonary complications after surgery.

RESULTS

A total of 46 patients were randomized in GR1 (n=24) and GR2 (n=22). Both groups were comparable with regard to age, height, weight, smoking history, baseline body plethysmography (FVC, FEV1, and RAW), and the severity of COPD according to the Global Initiative for Obstructive Lung Disease (GOLD) staging, respectively. However, the short-term effects of the treatment with regard to FEV1 (2.0 l vs 1.7 l; p=0.031) and increase of FEV1 (0.31 l vs 0.10 l; p=0.02) were better in GR1. More patients in GR1 had an improvement of ≥ 10% in FEV1 (p=0.004) and improvement of the severity of COPD (p=0.012) after the 1-week treatment. Fewer pulmonary complications (11.1% vs 42.9%, p=0.04) were observed in GR1 after surgery.

CONCLUSIONS

Both therapies resulted in an improvement of lung function. There is benefit from adding inhalative budenoside to tiotropium and formoterol in terms of an improvement in FEV1 and the severity of COPD. These beneficial results might lead to less pulmonary complications in the postoperative period.

The effects of sleep hypoxia on coagulant factors and hepatic inflammation in emphysematous rats

Objectives

To develop a sleep hypoxia (SH) in emphysema (SHE) rat model and to explore whether SHE results in more severe hepatic inflammation than emphysema alone and whether the inflammation changes levels of coagulant/anticoagulant factors synthesized in the liver.

Methods

Seventy-five rats were put into 5 groups: SH control (SHCtrl), treated with sham smoke exposure (16 weeks) and SH exposure (12.5% O₂, 3 h/d, latter 8 weeks); emphysema control (ECtrl), smoke exposure and sham SH exposure (21% O₂); short SHE (SHEShort), smoke exposure and short SH exposure (1.5 h/d); mild SHE (SHEMild), smoke exposure and mild SH exposure (15% O₂); standard SHE (SHEStand), smoke exposure and SH exposure. Therefore, ECtrl, SHEShort, SHEMild and SHEStand group were among emphysematous groups. Arterial blood gas (ABG) data was obtained during preliminary tests. After exposure, hepatic inflammation (interleukin -6 [IL-6] mRNA and protein, tumor necrosis factor α [TNFα] mRNA and protein) and liver coagulant/anticoagulant factors (antithrombin [AT], fibrinogen [FIB] and Factor VIII [F VIII]) were evaluated. SPSS 11.5 software was used for statistical analysis.

Results

Characteristics of emphysema were obvious in emphysematous groups and ABGs reached SH criteria on hypoxia exposure. Hepatic inflammation parameters and coagulant factors are the lowest in SHCtrl and the highest in SHEStand while AT is the highest in SHCtrl and the lowest in SHEStand. Inflammatory cytokines of liver correlate well with coagulant factors positively and with AT negatively.

Conclusions

When SH is combined with emphysema, hepatic inflammation and coagulability enhance each other synergistically and produce a more significant liver-derivative inflammatory and prothrombotic status.

Interleukin-6 and airflow limitation in chemical warfare patients with chronic obstructive pulmonary disease

OBJECTIVES

Chronic obstructive pulmonary disease (COPD) is one of the main late complications of sulfur mustard poisoning. The aim of this study was to evaluate serum levels of interleukin (IL)-6 in war veterans with pulmonary complications of sulfur mustard poisoning and their correlation with severity of airways disease.

METHODS

Fifty consecutive patients with sulfur mustard poisoning and stable COPD, and of mean age 46.3 ± 9.18 years were enrolled in this study. Thirty healthy men were selected as controls and matched to cases by age and body mass index. Spirometry, arterial blood gas, six- minute walk test, BODE (body mass index, obstruction, dyspnea, and exercise capacity), and St George's Respiratory Questionnaire about quality of life were evaluated. Serum IL-6 was measured in both patient and control groups.

RESULTS

Fifty-four percent of patients had moderate COPD. Mean serum IL-6 levels were 15.01 ± standard deviation (SD) 0.61 pg/dL and 4.59 ± 3.40 pg/dL in the case and control groups, respectively (P = 0.03). There was a significant correlation between IL-6 levels and Global Initiative for Chronic Obstructive Lung Disease stage (r = 0.25, P = 0.04) and between IL-6 and BODE index (r = 0.38, P = 0.01). There was also a significant negative correlation between serum IL-6 and forced expiratory volume in one second (FEV(1), r = -0.36, P = 0.016).

CONCLUSION

Our findings suggest that serum IL-6 is increased in patients with sulfur mustard poisoning and COPD, and may have a direct association with airflow limitation.

Cigarette smoke induces PTX3 expression in pulmonary veins of mice in an IL-1 dependent manner

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is associated with abnormal inflammatory responses and structural alterations of the airways, lung parenchyma and pulmonary vasculature. Since Pentraxin-3 (PTX3) is a tuner of inflammatory responses and is produced by endothelial and inflammatory cells upon stimuli such as interleukin-1β (IL-1β), we hypothesized that PTX3 is involved in COPD pathogenesis.

METHODS AND RESULTS

We evaluated whether cigarette smoke (CS) triggers pulmonary and systemic PTX3 expression in vivo in a murine model of COPD. Using immunohistochemical (IHC) staining, we observed PTX3 expression in endothelial cells of lung venules and veins but not in lung arteries, airways and parenchyma. Moreover, ELISA on lung homogenates and semi-quantitative scoring of IHC-stained sections revealed a significant upregulation of PTX3 upon subacute and chronic CS exposure. Interestingly, PTX3 expression was not enhanced upon subacute CS exposure in IL-1RI KO mice, suggesting that the IL-1 pathway is implicated in CS-induced expression of vascular PTX3. Serum PTX3 levels increased rapidly but transiently after acute CS exposure.To elucidate the functional role of PTX3 in CS-induced responses, we examined pulmonary inflammation, protease/antiprotease balance, emphysema and body weight changes in WT and Ptx3 KO mice. CS-induced pulmonary inflammation, peribronchial lymphoid aggregates, increase in MMP-12/TIMP-1 mRNA ratio, emphysema and failure to gain weight were not significantly different in Ptx3 KO mice compared to WT mice. In addition, Ptx3 deficiency did not affect the CS-induced alterations in the pulmonary (mRNA and protein) expression of VEGF-A and FGF-2, which are crucial regulators of angiogenesis.

CONCLUSIONS

CS increases pulmonary PTX3 expression in an IL-1 dependent manner. However, our results suggest that either PTX3 is not critical in CS-induced pulmonary inflammation, emphysema and body weight changes, or that its role can be fulfilled by other mediators with overlapping activities.

Characterisation of COPD heterogeneity in the ECLIPSE cohort

Background

Chronic obstructive pulmonary disease (COPD) is a complex condition with pulmonary and extra-pulmonary manifestations. This study describes the heterogeneity of COPD in a large and well characterised and controlled COPD cohort (ECLIPSE).

Methods

We studied 2164 clinically stable COPD patients, 337 smokers with normal lung function and 245 never smokers. In these individuals, we measured clinical parameters, nutritional status, spirometry, exercise tolerance, and amount of emphysema by computed tomography.

Results

COPD patients were slightly older than controls and had more pack years of smoking than smokers with normal lung function. Co-morbidities were more prevalent in COPD patients than in controls, and occurred to the same extent irrespective of the GOLD stage. The severity of airflow limitation in COPD patients was poorly related to the degree of breathlessness, health status, presence of co-morbidity, exercise capacity and number of exacerbations reported in the year before the study. The distribution of these variables within each GOLD stage was wide. Even in subjects with severe airflow obstruction, a substantial proportion did not report symptoms, exacerbations or exercise limitation. The amount of emphysema increased with GOLD severity. The prevalence of bronchiectasis was low (4%) but also increased with GOLD stage. Some gender differences were also identified.

Conclusions

The clinical manifestations of COPD are highly variable and the degree of airflow limitation does not capture the heterogeneity of the disease.

Sex differences in mortality and clinical expressions of patients with chronic obstructive pulmonary disease. The TORCH experience

RATIONALE

There is limited knowledge regarding sex differences and outcomes in patients with chronic obstructive pulmonary disease (COPD).

OBJECTIVES

Determine sex differences in survival, causes of death, and patient-centered outcomes in the 3-year Toward a Revolution in COPD Health (TORCH) study.

METHODS

A total of 1,481 women and 4,631 men with COPD were enrolled in TORCH, a trial comparing salmeterol, 50 μg, plus fluticasone propionate, 500 μg, twice a day and each component individually. Causes of death were determined by an endpoint committee. Sex differences in survival were explored using a Cox proportional hazards model adjusted for other baseline factors. Exacerbation rate was compared using a negative binomial model. Dyspnea was evaluated using the Medical Research Council scale and health status using the St. George's Respiratory Questionnaire.

MEASUREMENTS AND MAIN RESULTS

At baseline, women were younger (63 vs. 66 yr), had higher FEV(1) (47% vs. 44% predicted), and worse St. George's Respiratory Questionnaire (51.3 vs. 48.7) and Medical Research Council score. During the study, 707 (15.3%) men and 168 (11.3%) women died. After adjusting for differences in baseline factors, the risk of dying was 16% higher in men than in women; however, this was not statistically significant (hazard ratio 1.16 [95% CI, 0.98-1.39]). Causes of death were similar in women and men. Exacerbation rate was 25% higher in women than in men.

CONCLUSIONS

Women enrolled in TORCH had a lower mortality rate than men but similar causes of death. The risk of dying was similar in women and men after adjusting for important baseline variables. Women reported more exacerbations, and worse dyspnea and health status scores than men. Clinical trial registered with www.clinicaltrials.gov (NCT00268216).

Chronic respiratory disease and multimorbidity: prevalence and impact in a general practice setting

BACKGROUND

Multimorbidity is defined as two or more co-existing chronic conditions in an individual and is common in general practice. It is associated with poorer outcomes for patients. This study aimed to establish the prevalence of multimorbidity in patients with chronic respiratory disease in general practice and to describe its impact on health service use.

METHODS

Cross-sectional study based in general practice in Dublin. Drug and disease code searches were performed to identify adult patients with a diagnosis of chronic respiratory disease. Medical records were reviewed for chronic respiratory diagnosis, other chronic conditions, demographic characteristics, General Practitioner (GP) and practice nurse utilisation rates, and numbers of medications.

RESULTS

In a general practice population of 16,946 patients 3.9% had chronic respiratory disease and 60% of these had one or more co-existing chronic condition(s). GP and practice nurse utilisation rates, and number of medications were significantly higher among those with multimorbidity compared with those with respiratory disease alone. Multivariate analysis showed that increasing age and low socio-economic status were significantly associated with multimorbidity.

CONCLUSION

The majority of patients with chronic respiratory disease have multimorbidity. Clinical guidelines based on single disease entities and outcomes are not as easy to implement and may not be as effective in this group.

The T-helper cell type 1 immune response to gram-negative bacterial infections is impaired in COPD

RATIONALE

The increased susceptibility to bacterial infections in chronic obstructive pulmonary disease (COPD) is critical for exacerbations. Toll-like receptor-4 (TLR4) detects bacteria via LPS and induces IFN-γ-based immune responses. The direct responsiveness of Th1 lymphocytes to LPS is disputed because they lack surface expression of the TLR4 coreceptor CD14.

OBJECTIVES

We hypothesized that the Th1-mediated adaptive immune response to bacterial infections is impaired in COPD.

METHODS

LPS-induced TLR4 expression and IFN-γ release in and from ex vivo-generated Th1 cells was compared among nonsmokers (n = 14), smokers without COPD (n = 13), and smokers with COPD (n = 25) via quantitative reverse transcription polymerase chain reaction, Western blot, and ELISA. TLR4 transfection experiments were performed to functionally link receptor to IFN-γ dysregulation in COPD.

MEASUREMENTS AND MAIN RESULTS

Short-chain LPS from Salmonella species and nontypeable Haemophilus influenzae and nontypeable Haemophilus influenzae whole-cell extract all induced TLR4 expression via TLR4/MyD88/IRAK/mitogen-activated protein-kinase signaling and IFN-γ release via TLR4/TRIF/IKKε/TBK1 signaling in Th1 cells of nonsmokers. These effects were all impaired in smokers with and without COPD. The LPS responses were partially dependent on soluble CD14 and correlated positively to lung-function parameters but negatively to cigarette smoking (pack-years). Endogenous MyD88/IRAK signaling antagonists were up-regulated in Th1 cells of smokers and COPD, and TLR4 overexpression in Th1 cells of COPD restored LPS-dependent IFN-γ release.

CONCLUSIONS

Th1 cells directly respond to short-chain LPS. Cigarette smoking suppresses Th1-mediated immune responses to gram-negative bacterial infections by interfering with MyD88/IRAK signaling thereby reducing LPS-induced TLR4 expression. This can explain the increased susceptibility to bacterial infections in COPD. Targeting TLR signaling might be useful to reduce exacerbation rates.

Increased adipose tissue expression of proinflammatory CD40, MKK4 and JNK in patients with very severe chronic obstructive pulmonary disease

BACKGROUND

CD40, a transmembrane receptor of the tumor necrosis factor gene superfamily, is activated in response to cellular stress, including hypoxia, and orchestrates the process of inflammation via secondary messengers such as mitogen-activated protein kinase kinase 4 (MKK4) and c-Jun NH(2)-terminal kinases (JNK).

OBJECTIVES

We hypothesized that CD40, MKK4 and JNK expression is increased in the adipose tissue of patients with very severe chronic obstructive pulmonary disease (COPD).

METHODS

In 20 patients with stable COPD, lung function was assessed using body plethysmography, and samples of subcutaneous adipose tissue were analyzed using real-time PCR. Body composition, including fat mass index (FMI), was assessed by bioelectrical impedance.

RESULTS

12 patients in GOLD stage I-III (age 61.6 ± 8.6 years, 4 females, mean partial pressure of oxygen in arterial blood, PaO(2), 9.38 ± 0.21 kPa) were compared to 8 patients in GOLD stage IV (age 62.6 ± 6.3 years, all male, mean PaO(2) 7.70 ± 0.37 kPa). Compared to patients in GOLD stage I-III, patients in GOLD stage IV had lower FMI (p = 0.004), being associated with significantly higher adipose tissue expression of CD40, MKK4 and JNK [ΔΔCt: 2.55 (1.99, 4.40) vs. 1.87 (1.63, 2.23), p = 0.013; 5.19 (3.13, 5.96) vs. 2.98 (2.82, 3.86), p = 0.002; 9.01 (5.12, 11.41) vs. 4.65 (4.42, 6.26), p = 0.001, respectively]. Log-transformed CD40, MKK4 and JNK expression was significantly inversely related to PaO(2), respectively.

CONCLUSIONS

Upregulation of proinflammatory CD40, MKK4 and JNK gene expression in adipose tissue in very severe COPD raises the possibility of a role of chronic systemic hypoxia in the pathogenesis of adipose tissue inflammation in COPD.

Lung function and blood markers of nutritional status in non-COPD aging men with smoking history: a cross-sectional study

Purpose:

Cigarette smoking and advanced age are well known as risk factors for chronic obstructive pulmonary disease (COPD), and nutritional abnormalities are important in patients with COPD. However, little is known about the nutritional status in non-COPD aging men with smoking history. We therefore investigated whether reduced lung function is associated with lower blood markers of nutritional status in those men.

Subjects and methods:

This association was examined in a cross-sectional study of 65 Japanese male current or former smokers aged 50 to 80 years: 48 without COPD (non-COPD group), divided into tertiles according to forced expiratory volume in one second as percent of forced vital capacity (FEV₁/FVC), and 17 with COPD (COPD group).

Results:

After adjustment for potential confounders, lower FEV₁/FVC was significantly associated with lower red blood cell count (RBCc), hemoglobin, and total protein (TP); not with total energy intake. The difference in adjusted RBCc and TP among the non-COPD group tertiles was greater than that between the bottom tertile in the non-COPD group and the COPD group.

Conclusion:

In non-COPD aging men with smoking history, trends toward reduced nutritional status and anemia may independently emerge in blood components along with decreased lung function even before COPD onset.

Metabolic syndrome is associated with increased risk of acute exacerbation of COPD: a preliminary study

Studies have confirmed correlation between metabolic syndrome (MetS) and chronic obstructive pulmonary disease (COPD). However, to date, no studies have analyzed correlation between exacerbations of COPD (ECOPD) and MetS. The aim of this preliminary study was to examine if presence of MetS increases the frequency and duration of ECOPD. Patients with COPD were prospectively enrolled and followed between March 2008 and September 2009. Medical records, pulmonary function tests, chest X-rays; laboratory test results were gathered to establish the presence of COPD and MetS. Patients were divided in two groups; with and without MetS. The ECOPD was defined as worsening of symptoms requiring increased use of rescue medications and/or need for either systemic steroids or antibiotics or that led to emergency room visit or hospitalizations during 12 months follow-up. A total of 106 patients were recruited, 29 with MetS and 77 without. The mean exacerbation of COPD frequency was 2.4 ± 0.8 in MetS group versus 0.68 ± 0.6 in the control group during the follow-up period (P < 0.001). Mean duration of each exacerbation was 7.5 ± 1.5 days in patients with MetS versus 5 ± 2.4 days in patients without. Serum C-reactive protein (r = 0.31, P = 0.001), fasting blood glucose (r = 0.55, P < 0.001), and triglycerides (r = 0.251, P = 0.01) were positively and significantly correlated with exacerbation frequency. This study demonstrates an association between ECOPD and its duration with the MetS. The systemic inflammation induced by common cytokines may explain the linkage between the two conditions.

Loci identified by genome-wide association studies influence different disease-related phenotypes in chronic obstructive pulmonary disease

RATIONALE

Genome-wide association studies have shown significant associations between variants near hedgehog interacting protein HHIP, FAM13A, and cholinergic nicotinic acetylcholine receptor CHRNA3/5 with increased risk of chronic obstructive pulmonary disease (COPD) in smokers; however, the disease mechanisms behind these associations are not well understood.

OBJECTIVES

To identify the association between replicated loci and COPD-related phenotypes in well-characterized patient populations.

METHODS

The relationship between these three loci and COPD-related phenotypes was assessed in the Evaluation of COPD Longitudinally to Identify Predictive Surrogate End-point (ECLIPSE) cohort. The results were validated in the family-based International COPD Genetics Network (ICGN).

MEASUREMENTS AND MAIN RESULTS

The CHRNA3/5 locus was significantly associated with pack-years of smoking (P = 0.002 and 3 × 10⁻⁴), emphysema assessed by a radiologist using high-resolution computed tomography (P = 2 × 10⁻⁴ and 4.8 × 10⁻⁵), and airflow obstruction (P = 0.004 and 1.8 × 10⁻⁵) in the ECLIPSE and ICGN populations, respectively. However, variants in the IREB2 gene were only significantly associated with FEV₁. The HHIP locus was not associated with smoking intensity but was associated with FEV₁/FVC (P = 1.9 × 10⁻⁴ and 0.004 in the ECLIPSE and ICGN populations). The HHIP locus was also associated with fat-free body mass (P = 0.007) and with both retrospectively (P = 0.015) and prospectively (P = 0.024) collected COPD exacerbations in the ECLIPSE cohort. Single-nucleotide polymorphisms in the FAM13A locus were associated with lung function.

CONCLUSIONS

The CHRNA3/5 locus was associated with increased smoking intensity and emphysema in individuals with COPD, whereas the HHIP and FAM13A loci were not associated with smoking intensity. The HHIP locus was associated with the systemic components of COPD and with the frequency of COPD exacerbations. FAM13A locus was associated with lung function.

Emphysema is associated with increased inflammation in lungs of atherosclerosis-prone mice by cigarette smoke: implications in comorbidities of COPD

Background

Chronic obstructive pulmonary disease is associated with numerous vascular effects including endothelial dysfunction, arterial stiffness and atherogenesis. It is also known that a decline in lung function is associated with increased cardiovascular comorbidity in smokers. The mechanism of this cardiopulmonary dual risk by cigarette smoke (CS) is not known. We studied the molecular mechanisms involved in development of emphysema in atherosclerosis-prone apolipoprotein E-deficient (ApoE^-/-) mice in response to CS exposure.

Methods

Adult male and female wild-type (WT) mice of genetic background C57BL/6J and ApoE^-/- mice were exposed to CS, and lung inflammatory responses, oxidative stress (lipid peroxidation products), mechanical properties as well as airspace enlargement were assessed.

Results and Discussion

The lungs of ApoE^-/- mice showed augmented inflammatory response and increased oxidative stress with development of distal airspace enlargement which was accompanied with decline in lung function. Interestingly, the levels and activities of matrix metalloproteinases (MMP-9 and MMP-12) were increased, whereas the level of eNOS was decreased in lungs of CS-exposed ApoE^-/- mice as compared to air-exposed ApoE^-/- mice or CS-exposed WT mice.

Conclusion

These findings suggest that CS causes premature emphysema and a decline of lung function in mice susceptible to cardiovascular abnormalities via abnormal lung inflammation, increased oxidative stress and alterations in levels of MMPs and eNOS.

Roflumilast: first phosphodiesterase 4 inhibitor approved for treatment of COPD

In April 2010, the European Medicines Agency Committee for Medicinal Products for Human Use recommended approval of roflumilast, a selective phosphodiesterase 4 inhibitor, for the “maintenance treatment of severe chronic obstructive pulmonary disease (COPD, FEV₁ postbronchodilator less than 50% predicted) associated with chronic bronchitis in adult patients with a history of frequent exacerbations as add-on to bronchodilator treatment”. This decision was based, in part, on the results of several large, international, multicenter, randomized, placebo-controlled trials of either six or 12 months’ duration that had been undertaken in COPD patients. Roflumilast 500 μg daily improved lung function and reduced exacerbations in patients with more severe COPD, especially those with chronic bronchitis, frequent exacerbations, or who required frequent rescue inhaler therapy in the placebo-controlled trials. It also improved lung function and reduced exacerbations in patients with moderately severe COPD treated with salmeterol or tiotropium. Advantages of roflumilast over inhaler therapy are that it is an oral tablet and only needs to be taken once daily. While taking roflumilast, the most common adverse effects patients experienced were gastrointestinal upset and headache. Weight loss, averaging 2.2 kg, occurred in patients treated with roflumilast. Patients taking roflumilast were more likely to drop out of the trials than patients in the control groups. Patients who discontinued therapy usually did so during the first few weeks and were more likely to have experienced gastrointestinal side effects. Roflumilast is the first selective phosphodiesterase 4 inhibitor and will offer physicians another treatment option for patients with more severe COPD.

Caregiving burden and quality of life of pneumoconiosis caregivers in Hong Kong

OBJECTIVE

Silicosis is the most common type of pneumoconiosis in Hong Kong. This study explored the clinical correlates of the caregiving burden and quality of life (QOL) among pneumoconiosis caregivers in Hong Kong.

METHODS

The study sample included 112 patients with pneumoconiosis and their caregivers. Caregiving burden was measured using the Caregiving Burden Scale (CBS), and caregivers' QOL was assessed using the physical and mental components (PCS and MCS, respectively) of the Medical Outcomes Short Form-36. Pearson's correlation coefficient and Spearman's ρ were calculated to examine the relationship between CBS, PCS, and MCS scores and caregivers' and patients' sociodemographic variables. Stepwise regression analyses were performed to determine the independent correlates of CBS, PCS, and MCS scores.

RESULTS

Caregiving burden was correlated with certain patient characteristics (duration of disease, severity of dyspnea, exercise tolerance, depressive symptoms, daily functioning, and community living skills) and with caregivers' variables (depressive symptoms and availability of family support). Regression analysis showed that patients' daily functioning (β = -.345), caregivers' depressive symptoms (β = .509), and the availability of family support (β = .240) were independent correlates of caregiving burden, explaining 45% of the variance. The independent correlates of PCS included patients' severity of coexisting diseases (β = -.179) and caregivers' depressive symptoms (β = -.521). Both patients' (β = -.155) and caregivers' (β = -.633) depressive symptoms and patients' severity of dyspnea (β = -.183) were independent correlates of the MCS.

CONCLUSION

Caring for pneumoconiosis patients entails a significant caregiving burden for caregivers, and adversely affects their QOL. Caregivers' depressive symptoms are related to both their caregiving burden and QOL.

Influencing the decline of lung function in COPD: use of pharmacotherapy

Chronic obstructive pulmonary disease (COPD) is a common and deadly disease. One of the hallmarks of COPD is an accelerated decline in lung function, as measured by spirometry. Inflammation, oxidative stress and other pathways are hypothesized to be important in this deterioration. Because progressive airflow obstruction is associated with considerable morbidity and mortality, a major goal of COPD treatment has been to slow or prevent the accelerated decline in lung function. Until recently, the only known effective intervention was smoking cessation. However, newly reported large clinical trials have shown that commonly used medications may help slow the rate of lung function decline. The effect of these medications is modest (and thus required such large, expensive trials) and to be of clinical benefit, therapy would likely need to start early in the course of disease and be prolonged. Such a treatment strategy aimed at preservation of lung function would need to be balanced against the side effects and costs of prolonged therapy. A variety of newer classes of medications may help target other pathophysiologically important pathways, and could be used in the future to prevent lung function decline in COPD.

Inhaled albuterol/salbutamol and ipratropium bromide and their combination in the treatment of chronic obstructive pulmonary disease

IMPORTANCE OF THE FIELD

Chronic obstructive pulmonary disease (COPD) is a major cause of morbidity and mortality throughout the world. Combination therapy with albuterol and ipratropium bromide was approved > 15 years ago for the treatment of COPD. We review the mechanism of action, clinical efficacy, and safety of albuterol, ipratropium and combined albuterol-ipratropium therapy.

AREAS COVERED IN THIS REVIEW

We conducted a PubMed literature search using the keywords COPD, albuterol, ipratropium bromide and Combivent (Boehringer Ingelheim Corp., Ridgefield, CT, USA); pertinent references within the identified citations are included in the review. Data from the manufacturers are also evaluated.

WHAT THE READER WILL GAIN

At the time of its approval, albuterol/ipratropium bromide was an innovative combination of existing medications for the treatment of COPD. The combined formulation provides better improvement in airflow than either component alone and, by reducing the number of separate inhalers, simplifies therapy and improves compliance compared with the individual components.

TAKE HOME MESSAGE

The recent development and approval of longer acting and more potent beta agonists, anticholinergics and newer combination treatments have surpassed many of the advantages of combined albuterol-ipratropium for the treatment of patients with stable COPD.