[COPD and inflammation: statement from a French expert group: inflammation and remodelling mechanisms]

Cytokine profile in the sputum of subjects with post-tuberculosis airflow obstruction and in those with tobacco related chronic obstructive pulmonary disease

BACKGROUND

Previous studies have shown that tuberculosis (TB) is a risk factor for chronic airflow limitation. Chronic obstructive pulmonary disease (COPD) is recognized as the result of chronic inflammation, usually related to noxious particles. Post-TB airflow obstruction and tobacco-related COPD have the same functional pathway characterized by persistent airflow limitation. We sought to compare the profile of 29 cytokines in the sputum of subjects with post-TB airflow obstruction and those with COPD related to tobacco.

RESULTS

The forced expiratory volume in the first second (FEV1) and forced expiratory volume/forced vital capacity (FEV/FVC) ratio were lower in the COPD patients with the history of smoking compared to the post-TB airflow obstruction subgroup. The stages of the disease were more advanced in COPD / tobacco patients. Among the cytokines, IL-1α, IL-1β, MIP-1β, sCD40L and VEGF levels were higher in COPD patients, compared to the controls with p values ​​of 0.003, 0.0001, 0.03, 0.0001 and 0.02 respectively. When the two COPD subgroups were compared, IL-1α, IL-6, TNF-α and IL-8 levels were higher in the COPD patients with the history of tobacco compared to the COPD patients with the history of TB with p-values ​​of 0.031, 0.05, 0.021 and 0.016, respectively.

CONCLUSION

COPD related to tobacco is more severe than post-TB airflow obstruction. The pathogenesis of post-TB airflow obstruction appears to involve the cytokines IL-1RA, IL-1α, IL-1β, IL-17, GRO and sCD40L, while COPD related to tobacco involves more cytokines.

[Systemic inflammatory profile of smokers with and without COPD]

INTRODUCTION

Studies comparing the systemic inflammatory profiles of smokers with and without COPD present discordant findings.

AIM

To compare the systemic inflammatory profile of smokers with and without COPD.

METHODS

This is a cross-sectional comparative study. Two groups of active smokers of more than 10 pack-years were included: 56 consecutives stable COPD (postbronchodilator FEV₁/FVC<0.70) and 32 consecutives non-COPD (postbronchodilator FEV₁/FVC≥0.70). Smoking and clinical, anthropometric and spirometric data were noted. The following blood biomarkers were identified: leukocytes, hemoglobin, tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), C-reactive protein (CRP), erythrocyte sedimentation rate (ESR). According to the levels (normal/abnormal) of these markers, two groups of smokers were formed. Quantitative and qualitative data were expressed, respectively, as means±SD and percentages.

RESULTS

Compared to the non-COPD group, the COPD group was older (56±12 vs. 65±8 years) and had a higher smoking consumption (30±18 vs. 52±31 pack-years). Compared to the non-COPD group, the COPD group had higher values of CRP (2.06±1.24 vs. 11.32±11.03mg/L), of ESR (9.59±8.29 vs. 15.96±11.56), of IL-6 (9.28±4.69 vs. 20.27±5.31ng/L) and of TNF-α (18.38±7.98ng/L vs. 8.62±3.72ng/L). Compared to the non-COPD group, the COPD group included higher percentages of smokers with elevated CRP (0 % vs. 32 %), with leukocytosis (6 % vs. 16 %), with higher levels of IL-6 (81 % vs. 98 %) or TNF-α (91 % vs. 100 %).

CONCLUSION

Smokers with COPD, compared to smokers free from COPD, have a marked systemic inflammation.

Risk of cardiovascular events after initiation of long-acting bronchodilators in patients with chronic obstructive lung disease: A population-based study

Objectives:

Long-acting bronchodilators are mainstay treatment for moderate to severe chronic obstructive pulmonary disease. A growing body of evidence indicates an increased risk of cardiovascular events upon initiation of these medications. We hypothesize that this risk is higher in patients with chronic obstructive pulmonary disease who had a preexisting cardiovascular disease regardless of receipt of any cardiovascular medication.

Methods:

A retrospective cohort of patients with a diagnosis of chronic obstructive pulmonary disease based on two outpatient visits or one inpatient visit for chronic obstructive pulmonary disease (International Classification of Diseases, 9th Edition, Clinical Modification codes 491.x, 492.x, 496) in any year between 2001 and 2012 from a commercial insurance database. We then selected those initiating long-acting bronchodilator treatments between April 2001 and September 2012. Each patient had a 1 year look back period to determine history of cardiovascular disease or cardiovascular disease treatment from the time of first prescription of long-acting beta agonist, long-acting muscarinic antagonist, or long-acting beta agonist combined with inhaled corticosteroids. Patients were followed for 90 days for hospitalizations or emergency department visits for cardiovascular event. The cohort was divided into four groups based on the presence of cardiovascular disease (including ischemic heart disease, hypertension, ischemic stroke, heart failure, tachyarrhythmias and artery disease based on International Classification of Diseases, 9th Edition, Clinical Modification codes) and cardiovascular disease treatment defined as acetylsalicylic acid, beta blockers, angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, antiplatelet, anticoagulants, calcium channel blockers, nitrate, digoxin, diuretics, antiarrhythmics or statins. Odds of emergency department visit or hospitalization in the 90 days after prescription were examined using multivariable logistic regression models.

Results:

Of 61,651 eligible patients, 36,755 (59.6%) had cardiovascular disease and were on cardiovascular disease treatment (Group 1), 7250 (11.8%) had cardiovascular disease without cardiovascular disease treatment (Group 2), 4715 (7.7%) had no cardiovascular disease but had cardiovascular disease treatment (Group 3) and 12,931 (21%) had no cardiovascular disease and no treatment (Group 4). In these four groups, the unadjusted risk of emergency department visit or hospitalization for cardiovascular disease within 90 days of initiation was 5.45%, 2.95%, 1.55% and 0.96%, respectively. In multivariable analysis, the adjusted odds ratio with 95% confidence interval of emergency department visit/hospitalization for each of the first three groups to those with no cardiovascular disease and no treatment were 3.50 (95% confidence interval, 2.89–4.24), 2.15 (95% confidence interval, 1.71–2.70) and 1.36 (95% confidence interval, 1.01–1.82), respectively.

Conclusion:

The risk of cardiovascular events after initiation of long-acting bronchodilators is highest in patients with baseline cardiovascular disease and on cardiovascular disease medications. Clinicians should be cautious while prescribing these medications in patients with preexisting cardiovascular disease.

In Vivo Computed Tomography as a Research Tool to Investigate Asthma and COPD: Where Do We Stand?

Computed tomography (CT) is a clinical tool widely used to assess and followup asthma and chonic obstructive pulmonary disease (COPD) in humans. Strong efforts have been made the last decade to improve this technique as a quantitative research tool. Using semiautomatic softwares, quantification of airway wall thickness, lumen area, and bronchial wall density are available from large to intermediate conductive airways. Skeletonization of the bronchial tree can be built to assess its three-dimensional geometry. Lung parenchyma density can be analysed as a surrogate of small airway disease and emphysema. Since resident cells involve airway wall and lung parenchyma abnormalities, CT provides an accurate and reliable research tool to assess their role in vivo. This litterature review highlights the most recent advances made to assess asthma and COPD with CT, and also their drawbacks and the place of CT in clarifying the complex physiopathology of both diseases.

Beyond corticosteroids: future prospects in the management of inflammation in COPD

Inflammation plays a central role in the pathophysiology of chronic obstructive pulmonary disease (COPD). Exposure to cigarette smoke induces the recruitment of inflammatory cells in the airways and stimulates innate and adaptive immune mechanisms. Airway inflammation is involved in increased bronchial wall thickness, increased bronchial smooth muscle tone, mucus hypersecretion and loss of parenchymal elastic structures. Oxidative stress impairs tissue integrity, accelerates lung ageing and reduces the efficacy of corticosteroids by decreasing levels of histone deacetylase-2. Protease-antiprotease imbalance impairs tissues and is involved in inflammatory processes. Inflammation is also present in the pulmonary artery wall and at the systemic level in COPD patients, and may be involved in COPD-associated comorbidities. Proximal airways inflammation contributes to symptoms of chronic bronchitis while distal and parenchymal inflammation relates to airflow obstruction, emphysema and hyperinflation. Basal levels of airways and systemic inflammation are increased in frequent exacerbators. Inhaled corticosteroids are much less effective in COPD than in asthma, which relates to the intrinsically poor reversibility of COPD-related airflow obstruction and to molecular mechanisms of resistance relating to oxidative stress. Ongoing research aims at developing new drugs targeting more intimately COPD-specific mechanisms of inflammation, hypersecretion and tissue destruction and repair. Among new anti-inflammatory agents, phosphodiesterase-4 inhibitors have been the first to emerge.

[COPD and inflammation: statement from a French expert group. Phenotypes related to inflammation]

INTRODUCTION

The objective of the present article is to review available data on possible links between phenotypes and inflammatory profiles in patients with chronic obstructive pulmonary disease (COPD).

BACKGROUND

Chronic bronchitis is associated with proximal bronchial inflammation and small airway inflammation with remodeling at the site of obstruction. CT scanning enables patients to be phenotyped according to the predominantly bronchial or emphysematous nature of the morphological abnormality. Exacerbations, in a context of persistently elevated baseline inflammation, are associated with increased inflammation and a poor prognosis. Long-term studies have correlated inflammatory markers (and anti-inflammatory drug effects) with dynamic hyperinflation, possibly confirming that inflammation promotes hyperinflation. The inflammatory cell count in the pulmonary arterial walls correlates with the severity of endothelial dysfunction. The risk of developing pulmonary hypertension would seem to increase with low-grade systemic inflammation. The role of low-grade systemic inflammation in COPD co-morbidities, and in nutritional and muscular involvement in particular, remains a matter of debate. Regular physical exercise may help reduce this inflammation.

CONCLUSIONS

In COPD, many aspects of the clinical phenotype are related to inflammation. Better knowledge of these relationships could help optimize current and future treatments.