Steroid resistance in COPD? Overlap and differential anti-inflammatory effects in smokers and ex-smokers

Association of blood eosinophils with corticosteroid treatment failure stratified by smoking status among inpatients with AECOPD

BACKGROUND

Recent studies have suggested elevated blood eosinophils are independent predictors of response to corticosteroid therapy in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD). Smoking status has been shown to affect corticosteroid response. Whether the association between high blood eosinophils and corticosteroid treatment failure is modified by smoking has not been fully investigated so far.

OBJECTIVES

This study aimed to assess whether the association between high blood eosinophils and corticosteroid treatment failure is modified by smoking.

METHODS

We included 3402 inpatients with AECOPD treated with corticosteroids at Beijing Chao-Yang Hospital from July 2013 to June 2021. Blood eosinophil counts were measured within 24 hours of admission. An eosinophil percentage ≥2% was considered as high eosinophilic. Smokers in this study were defined as current or former smokers. Treatment failure was defined as a worsening of AECOPD that led to adverse clinical outcomes or required further treatment or an extended hospital stay or hospitalisation following the exacerbation. Multivariate-adjusted logistic models were used to estimate the OR and 95% CI associated with treatment failure.

RESULTS

There were 958 (28.2%) treatment failure events occurring. Patients with high eosinophils had a lower risk of treatment failure (OR 0.74, 95% CI 0.63 to 0.87) than patients with low eosinophils. Compared with never smoking and low eosinophilic group, the ORs for treatment failure were 0.70 (95% CI 0.52 to 0.96) for never smoking and high eosinophilic group, 0.82 (95% CI 0.64 to 1.05) for smoking and low eosinophilic group and 0.62 (95% CI 0.47 to 0.81) for smoking and high eosinophilic group. Furthermore, there was no significant interaction between eosinophils and smoking status in relation to treatment failure (p for interaction=0.73). Similar results were obtained from multiple secondary outcomes and subgroup analyses.

CONCLUSION

Elevated blood eosinophils are associated with a lower rate of corticosteroid treatment failure, regardless of smoking status. Smoking does not modify the association between blood eosinophil level and corticosteroid treatment failure among inpatients with AECOPD.

Stepwise management of COPD: What is next after bronchodilation?

Inhaled bronchodilator therapy with long-acting muscarinic antagonists (LAMAs) and long-acting β2-agonists (LABAs) in combination is currently the mainstay of treatment for chronic obstructive pulmonary disease (COPD). Treatment guidelines recommend the addition of inhaled corticosteroids (ICS) to LABA/LAMA only in patients with a history of frequent/severe exacerbations and high blood eosinophil counts, or in those with concomitant asthma. Despite this, real-world data suggest that clinicians are not adhering to this guidance and that ICS are frequently overused. This is possibly due to the incorrect assumption that when LABA/LAMA therapy is not sufficient, adding an ICS to the treatment regimen is the logical next step. In this narrative review, we describe global and country-specific guideline recommendations from Germany, Spain, and Japan and compare these with real-world data on LABA/LAMA and ICS use in clinical practice. We also provide a clinical guide to the use of add-on therapies with LABA/LAMA for different patient phenotypes, including (1) patients still symptomatic (but not exacerbating) despite LABA/LAMA treatment; (2) patients still exacerbating despite LABA/LAMA treatment who have high blood eosinophil counts; and (3) patients still exacerbating despite LABA/LAMA treatment who do not have high blood eosinophils or concomitant asthma.

IL-26 in the Lung and Its Role in COPD Inflammation

IL-26 is a cytokine expressed by infiltrating pro-inflammatory IL-17-producing T cells in the tissues of patients with chronic lung inflammation. IL-26 induces the chemotactic response of human neutrophils to bacteria and other inflammatory stimuli. In recent years, the innovative properties of IL-26 have been described. Studies have shown that, as DNA is released from damaged cells, it binds to IL-26, which plays the role of a carrier molecule for extracellular DNA, further contributing to its binding to the site of inflammation. This mechanism of action indicates that IL-26 may serve both as a driver as well as a stimulus of the inflammatory process, leading to the installation of a noxious amplification loop and, eventually, persistent inflammation. IL-26 also demonstrates direct antimicrobial effects derived from its capability to create pores and disrupt bacterial membranes, as indicated by the presence of membrane blebs on the surface of the bacteria and cytosolic leakage pores in bacterial walls, produced in response to microbial stimuli in human airways by several different immune and structural cells. Surprisingly, while this particular cytokine induces the gathering of neutrophils in areas of infection, it also exhibits inhibitory and pro-inflammatory effects on airway epithelial and immune cells. These remarkable effects underline the necessity of a better understating of its biological behavior and its role in the pathophysiology and disease burden in several smoking-related airway inflammatory disorders, such as Chronic Obstructive Pulmonary Disease (COPD) and chronic bronchitis. In this review, we aim to discuss the current role of IL-26 in the lung, with an emphasis on systemic inflammation in patients suffering from COPD and chronic bronchitis.

The Use of Inhaled Corticosteroids for Patients with COPD Who Continue to Smoke Cigarettes: An Evaluation of Current Practice

The use of inhaled corticosteroids (ICS) in combination with inhaled bronchodilators for patients with chronic obstructive pulmonary disease (COPD) is a common practice in primary care settings. However, ICS-containing therapies may be less effective in patients with COPD compared with asthma, and in individuals with COPD who continue to smoke cigarettes. Preclinical studies suggest that inflammation in COPD is very different from in asthma. Glucocorticoid receptor functioning and other innate anti-inflammatory mechanisms are altered in cells exposed to cigarette smoke. COPD may be relatively insensitive to ICS, especially in individuals who continue to smoke. ICS-containing therapies in patients with asthma who continue to smoke may also be less effective compared with patients who do not smoke. ICS-containing therapies may be inappropriately used in some patients with COPD, and their long-term use is associated with an increased risk for side effects, including pneumonia and bone fractures in some patients. Treatment for patients with COPD should be carefully evaluated, and anti-inflammatory/bronchodilatory strategies should be chosen based on individual patient characteristics and recommendations in current guidelines.

Pharmacotherapy of chronic obstructive pulmonary disease: Therapeutic considerations with a focus on inhaled corticosteroids

International and national guidelines on chronic obstructive pulmonary disease (COPD) emphasise bronchodilators as first-line therapy. However, in considering them the 'foundation' of treatment, attention has shifted from the fact that COPD is fundamentally an inflammatory disease. The mainstay ought to be anti-inflammatory medication, and inhaled corticosteroids (ICS) are the best agents we have presently. There was initial scepticism about their role, but ICS were subsequently shown to have numerous anti-inflammatory effects. They are synergistic with bronchodilators at a molecular and clinical level and unequivocally improve dyspnoea, quality of life, exacerbation frequency and, more recently, mortality. These benefits are most apparent in the COPD eosinophilic phenotype. These beneficial effects have been met with some reservations because of the predisposition to pneumonia of ICS. This must be seen in context: over 90% of COPD patients in all clinical trials do not get pneumonia. The fact that patients with COPD are predisposed to pneumonia because of the disease itself is disregarded; this is a crucial omission as this constitutes the baseline incidence of about 3%. When one allows for this, then in the clinical reports, the excess risk of pneumonia ranges from zero to a maximum of 3%. Equally, some of the systemic effects attributed to ICS fail to appreciate that the disease, smoking and older age are risk factors in themselves, and ICS do not aggravate these. Chronic obstructive pulmonary disease has considerable impact on respiratory reserve and is associated with increasing morbidity; optimal outcomes are best achieved with long-acting bronchodilators and ICS co-prescription.

Inhaled Corticosteroids in COPD: Trying to Make a Long Story Short

The use of inhaled corticosteroids (ICSs) in long-term treatment of COPD has been a debated topic for a long time. According to the evidence produced till now, ICSs are presently advocated in combination with long-acting bronchodilators for high-risk symptomatic COPD patients with a history of frequent COPD exacerbations. However, the heterogeneity of COPD patients in terms of prevalent underlying disease, with its associated biological and functional characteristics, and different types of exacerbation makes this recommendation highly questionable. This review aims to discuss the usefulness of ICSs in the pharmacological management of COPD and trys to detect those aspects that may likely anticipate a beneficial response following their therapeutic use related to respiratory function, functional decline, prevention of exacerbation, and quality of life. In this respect, the BERN acronym, meaning Bronchiolitis, Eosinophilia, Responsiveness to bronchodilator, and Non-smoker, may be of practical utility to select among COPD patients those that can take more advantage from ICS adoption when positive and vice versa when negative.

Impact of smoking status on the efficacy of inhaled corticosteroids in chronic obstructive pulmonary disease: a systematic review

OBJECTIVES

Inhaled corticosteroids (ICS) reduce exacerbation rates and the decline in lung function in people with chronic obstructive pulmonary disease (COPD). There is evidence that smoking causes 'steroid resistance' and thus reduces the effect of ICS. This systematic review aimed to investigate the effect of smoking on efficacy of ICS in COPD in terms of lung function and exacerbation rates.

DESIGN

Systematic review.

DATA SOURCES

An electronic database search of PubMed, Ovid MEDLINE, Ovid Embase and Cochrane Library (January 2000 to January 2020).

ELIGIBILITY CRITERIA

Fully published randomised controlled trials (RCTs), in the English language, evaluating the use of ICS in COPD adults that stratified the participants by smoking status. Trials that included participants with asthma, lung cancer and pneumonia were excluded. The primary outcome measures were changes in lung function and yearly exacerbation rates.

DATA EXTRACTION AND SYNTHESIS

Two independent reviewers extracted data and assessed risk of bias using the Cochrane Collaboration's tool.

RESULTS

Seven studies were identified. Four trials (17 892 participants) recorded change in forced expiratory volume in one second (FEV₁) from baseline to up to 30 months after starting treatment. Heavier smokers (>36 pack years) using ICS had a greater decline in FEV₁ that ranged from -22 mL to -75 mL in comparison to lighter smokers. Smokers using ICS had mixed results in FEV₁ change: -8 mL to +77 mL in comparison to ex-smokers. Four trials (21 270 participants) recorded difference in COPD exacerbation rates at 52 weeks. The rate ratios favoured more exacerbations in ICS users who were current or heavier smokers than those who were ex-smokers or lighter smokers (0.81 to 0.99 vs 0.92 to 1.29).

CONCLUSIONS

In COPD, heavier or current smokers do not gain the same benefit from ICS use on lung function and exacerbation rates as lighter or ex-smokers do, however effects may not be clinically important.

PROSPERO REGISTRATION NUMBER

CRD42019121833.

Inhaled corticosteroids for chronic obstructive pulmonary disease: what is their role in therapy?

Inhaled corticosteroids (ICSs) are a mainstay of COPD treatment for patients with a history of exacerbations. Initial studies evaluating their use as monotherapy failed to show an effect on rate of pulmonary function decline in COPD, despite improvements in symptoms and reductions in exacerbations. Subsequently, ICS use in combination with long-acting β2-agonists (LABAs) was shown to provide improved reductions in exacerbations, lung function, and health status. ICS-LABA combination therapy is currently recommended for patients with a history of exacerbations despite treatment with long-acting bronchodilators alone. The presence of eosinophilic bronchial inflammation, detected by high blood eosinophil levels or a history of asthma or asthma-COPD overlap, may define a population of patients in whom ICSs may be of particular benefit. Prospective clinical studies to determine an appropriate threshold of eosinophil levels for predicting the beneficial effects of ICSs are needed. Further study is also required in COPD patients who continue to smoke to assess the impact of cell- and tissue-specific changes on ICS responsiveness. The safety profile of ICSs in COPD patients is confounded by comorbidities, age, and prior use of systemic corticosteroids. The risk of pneumonia in patients with COPD is increased, particularly with more advanced age and worse disease severity. ICS-containing therapy also has been shown to increase pneumonia risk; however, differences in study design and the definition of pneumonia events have led to substantial variability in risk estimates, and some data indicate that pneumonia risk may differ by the specific ICS used. In summary, treatment with ICSs has a role in dual and triple therapy for COPD to reduce exacerbations and improve symptoms. Careful assessment of COPD phenotypes related to risk factors, triggers, and comorbidities may assist in individualizing treatment while maximizing the benefit-to-risk ratio of ICS-containing COPD treatment.

Inhaled corticosteroids in COPD: Personalising the therapeutic choice

There has been a recent surge in interest in the role of inhaled corticosteroids (ICS) in the treatment of COPD, especially regarding patients with high eosinophil counts. Evidence has shown that despite the increase in localised adverse effects and a small increase in non-fatal pneumonia events with ICS use, ICS still have an important role to play in reducing exacerbation rates and addressing the inflammation that is at the heart of the pathogenesis of COPD. Current international guidelines recommend the use of ICS only in patients with severe disease. This review examines the potential role of ICS in all COPD patients.

Inhaled corticosteroid normalizes some but not all airway vascular remodeling in COPD

BACKGROUND

This study assessed the effects of inhaled corticosteroid (ICS) on airway vascular remodeling in chronic obstructive pulmonary disease (COPD).

METHODS

Thirty-four subjects with mild-to-moderate COPD were randomly allocated 2:1 to ICS or placebo treatment in a double-blinded clinical trial over 6 months. Available tissue was compared before and after treatment for vessel density, and expression of VEGF, TGF-β1, and TGF-β1-related phosphorylated transcription factors p-SMAD 2/3. This clinical trial has been registered and allocated with the Australian New Zealand Clinical Trials Registry (ANZCTR) on 17/10/2012 with reference number ACTRN12612001111864.

RESULTS

There were no significant baseline differences between treatment groups. With ICS, vessels and angiogenic factors did not change in hypervascular reticular basement membrane, but in the hypovascular lamina propria (LP), vessels increased and this had a proportionate effect on lung air trapping. There was modest evidence for a reduction in LP vessels staining for VEGF with ICS treatment, but a marked and significant reduction in p-SMAD 2/3 expression.

CONCLUSION

Six-month high-dose ICS treatment had little effect on hypervascularity or angiogenic growth factors in the reticular basement membrane in COPD, but normalized hypovascularity in the LP, and this was physiologically relevant, though accompanied by a paradoxical reduction in growth factor expression.

Triple inhaled therapy for chronic obstructive pulmonary disease

Combining individual drugs in a single inhaler is the most convenient way to deliver triple therapy. A long-acting muscarinic receptor antagonist (LAMA) added to an inhaled corticosteroid (ICS)/long-acting β₂-adrenoceptor agonist (LABA) fixed-dose combination (FDC) can improve efficacy of pharmacological treatment of patients with chronic obstructive pulmonary disease (COPD). New inhaled ICS/LABA/LAMA FDCs, including fluticasone furoate/vilanterol/umeclidinium, budesonide/formoterol/glycopyrronium and beclometasone/formoterol/glycopyrronium, are in Phase III of clinical development for COPD. Triple inhaled therapy might be particularly useful in patients with severe to very severe COPD, above all in those with peripheral blood or sputum eosinophilia, asthma-COPD overlap syndrome (ACOS) or frequent exacerbators. Future prospective studies should assess efficacy and safety of triple ICS/LABA/LAMA therapy in selected COPD phenotypes.

Update on molecular mechanisms of corticosteroid resistance in chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is an inflammatory and irreversible pulmonary disorder that is characterized by inflammation and airway destruction. In recent years, COPD has become a global epidemic due to increased air pollution and exposure to cigarette smoke. Current therapeutics using bronchiodialator and anti-inflammatory corticosteroids are most widely used for all patients with persistent COPD, but these approaches are disappointing due to limited improvement in symptom control and survival rate. More importantly, a certain number of COPD patients are resistant to the corticosteroid treatment and their symptoms worsen. Therefore, more effective anti-inflammatory drugs and combinational treatment are required. Understanding of the underlying molecular and immunological mechanisms is critical to developing new therapeutics. Lung inflammation and the released pro-inflammatory cytokines affect glucocorticoid receptor (GR), histone deacetylase 2 (HDAC2) and surfactant protein D (SP-D) activities in many cell types. Macrophages, neutrophils, airway epithelial cells and lymphocytes are involved in the induction of corticosteroid resistance. This review updated the recent advances in molecular and immunological mechanisms of steroid resistance among patients and animal models with COPD. Meanwhile we discussed novel therapeutic approaches in controlling lung inflammation and improving corticosteroid sensitivity among the steroid resistant patients with COPD.

Real-life GOLD 2011 implementation: the management of COPD lacks correct classification and adequate treatment

Chronic obstructive pulmonary disease (COPD) is a serious, yet preventable and treatable, disease. The success of its treatment relies largely on the proper implementation of recommendations, such as the recently released Global Strategy for Diagnosis, Management, and Prevention of COPD (GOLD 2011, of late December 2011). The primary objective of this study was to examine the extent to which GOLD 2011 is being used correctly among Czech respiratory specialists, in particular with regard to the correct classification of patients. The secondary objective was to explore what effect an erroneous classification has on inadequate use of inhaled corticosteroids (ICS). In order to achieve these goals, a multi-center, cross-sectional study was conducted, consisting of a general questionnaire and patient-specific forms. A subjective classification into the GOLD 2011 categories was examined, and then compared with the objectively computed one. Based on 1,355 patient forms, a discrepancy between the subjective and objective classifications was found in 32.8% of cases. The most common reason for incorrect classification was an error in the assessment of symptoms, which resulted in underestimation in 23.9% of cases, and overestimation in 8.9% of the patients' records examined. The specialists seeing more than 120 patients per month were most likely to misclassify their condition, and were found to have done so in 36.7% of all patients seen. While examining the subjectively driven ICS prescription, it was found that 19.5% of patients received ICS not according to guideline recommendations, while in 12.2% of cases the ICS were omitted, contrary to guideline recommendations. Furthermore, with consideration to the objectively-computed classification, it was discovered that 15.4% of patients received ICS unnecessarily, whereas in 15.8% of cases, ICS were erroneously omitted. It was therefore concluded that Czech specialists tend either to under-prescribe or overuse inhaled corticosteroids.