Rapid corticosteroid effect on beta(2)-adrenergic airway and airway vascular reactivity in patients with mild asthma

Albuterol/budesonide for the treatment of exercise-induced bronchoconstriction in patients with asthma: The TYREE study

BACKGROUND

PT027 is a fixed-dose combination of albuterol (salbutamol) and budesonide in a single pressurized metered-dose inhaler.

OBJECTIVE

To evaluate the efficacy and safety of albuterol/budesonide compared with placebo in patients with asthma and exercise-induced bronchoconstriction (EIB).

METHODS

In this randomized, double-blind, 2-period, single-dose crossover study, adolescents and adults with asthma and EIB (defined by ≥20% decrease from pre-exercise challenge forced expiratory volume in 1 second [FEV₁]) were randomized to albuterol/budesonide (180/160 µg) followed by placebo (n = 29) or the reverse sequence (n = 31). Subjects were stratified by background therapy (as-needed short-acting β₂-agonist alone or low-to-medium dose inhaled corticosteroid plus as-needed short-acting β₂-agonist). FEV₁ was measured 5 minutes pre-dose, 30 minutes postdose (5 minutes pre-exercise challenge [baseline]), and 5, 10, 15, 30, and 60 minutes postexercise. The primary end point was maximum percentage fall from baseline in FEV₁ up to 60 minutes postexercise challenge.

RESULTS

Least squares mean maximum percentage fall in FEV₁ up to 60 minutes postexercise challenge was 5.45% with albuterol/budesonide vs 18.97% with placebo (difference, -13.51% [95% confidence interval, -16.94% to -10.09%]; P < .001). More subjects were fully protected (maximum percentage fall in FEV₁ post-exercise challenge < 10%) with albuterol/budesonide than with placebo (78.3% vs 28.3%; P < .001). The treatment effect was consistent irrespective of background inhaled corticosteroid therapy, and albuterol/budesonide was well tolerated.

CONCLUSION

In adolescents and adults with asthma and EIB, a single dose of albuterol/budesonide 180/160 µg taken approximately 30 minutes before exercise was significantly more effective than placebo in preventing EIB.

Dilatation Reserve of Pulmonary Arteries at Stages of the Chronic Obstructive Pulmonary Disease Model

OBJECTIVES

To assess the state of pulmonary vascular mediator systems during the stepwise formation of the chronic obstructive pulmonary disease (COPD) model.

MATERIALS AND METHODS

The COPD model was induced in rats by nitrogen dioxide (NO2) inhalation for 60 days. At different stages of COPD (15, 30, and 60 days), the effect of reagents-vasodilators (β-adrenoceptor agonist isoproterenol, nitric oxide donor nitrosorbide, acetylcholine, activator of C-fibers capsaicin, corticosteroid beclometasone) on the isolated pulmonary arteries (diameter <0.5 mm) was studied. Vascular reactivity was assessed by determining isometric contraction (tension in milligrams) of arterial rings by using an electromechanical transducer.

RESULTS

All vasodilators dose-dependently decreased the vascular tone of pulmonary arteries isolated from intact rats. After 15 days of NO2 exposure, dilatation effect of low doses of vasodilators did not differ from that of intact specimens. The functional state of the adrenergic system deteriorated faster than that of the nonadrenergic noncholinergic system as reflected by the weakening of the isoproterenol relaxation effect. On prolonged NO2 exposure, pulmonary arteries responded to the impact of all vasodilators with smaller relaxation. Dose dependence of the dilatation reaction disappeared for isoproterenol, capsaicin, beclometasone, and was less expressed for nitrosorbide and acetylcholine after 60 days of exposure.

CONCLUSION

In the course of COPD model generation, the functioning of almost all neurotransmitter systems of pulmonary artery wall was negatively affected. This led to a decrease in the influence of vasodilators on pulmonary artery vascular tone and could facilitate the development of pulmonary hypertension, which is typical of COPD.

Acute effect of an inhaled glucocorticosteroid on albuterol-induced bronchodilation in patients with moderately severe asthma

BACKGROUND

We have previously shown that in patients with asthma a single dose of an inhaled glucocorticosteroid (ICS) acutely potentiates inhaled albuterol-induced airway vascular smooth muscle relaxation through a nongenomic action. An effect on airway smooth muscle was not seen, presumably because the patients had normal lung function. The purpose of the present study was to conduct a similar study in patients with asthma with airflow obstruction to determine if an ICS could acutely also potentiate albuterol-induced airway smooth muscle relaxation in them.

METHODS

In 15 adult patients with asthma (mean ± SE baseline FEV1, 62% ± 3%), the response to inhaled albuterol (180 μg) was assessed by determining the change in FEV1 (ΔFEV1) for airway smooth muscle and in airway blood flow (ΔQaw) for airway vascular smooth muscle measured 15 min after drug inhalation. Using a double-blind design, the patients inhaled a single dose of the ICS mometasone (400 μg) or placebo simultaneously with or 30 min before albuterol inhalation.

RESULTS

After simultaneous drug administration, mean ΔFEV1 was 0.20 ± 0.05 L (10%) after placebo and 0.32 ± 0.04 L (19%) after mometasone (P < .05); mean ΔQaw was -2% after placebo and 30% after mometasone (P < .005). When mometasone or placebo was administered 30 min before albuterol, there was a lesser and insignificant difference in ΔFEV1 between the two treatments, whereas the difference in ΔQaw remained significant.

CONCLUSIONS

This pilot study showed that in adult patients with asthma with airflow obstruction, a single standard dose of an ICS can acutely increase the FEV1 response to a standard dose of inhaled albuterol administered simultaneously. The associated potentiation of albuterol-induced vasodilation in the airway was of greater magnitude and retained when the ICS was administered 30 min before albuterol. The clinical significance of this observation will have to be established by a study involving a larger patient cohort.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT01210170; URL: www.clinicaltrials.gov.

Immediate antiinflammatory effects of inhaled budesonide in patients with asthma

BACKGROUND

In patients with asthma, single doses of inhaled glucocorticosteroids (ICS) have been reported to have antiinflammatory actions that can be detected several hours after drug administration. However, the onset and duration of the effect have not been investigated. We therefore measured airway blood flow ([Formula: see text]aw) as an index of airway inflammation to determine the time course and dose dependence of the antiinflammatory action of an ICS in 20 patients with moderate asthma receiving regular ICS treatment.

METHODS

[Formula: see text]aw and spirometry were measured before and serially for 360 minutes after a single inhaled dose of 360 μg, 720 μg, and 1,440 μg budesonide or placebo as well as after four repetitive 720-μg budesonide doses given 30 minutes apart.

RESULTS

Baseline mean [Formula: see text]aw was increased and FEV1 was decreased without significant differences among the 5 treatment days. After budesonide inhalation, there was a transient, dose-dependent decrease in mean [Formula: see text]aw from 12 to 21%, with significant differences from baseline at 60 and 90 minutes for the 720-μg and 1,440-μg doses (P < 0.05). Thirty minutes after four repetitive budesonide administrations, mean [Formula: see text]aw was 28% below baseline (P < 0.05) and remained 11% below baseline after 270 minutes. There was no change in mean FEV1 after any of the treatments.

CONCLUSIONS

In subjects with moderate asthma who use ICS regularly, inhaled budesonide caused a transient dose-dependent vasoconstriction in the airway, thereby reversing one manifestation of airway inflammation. These results suggest that a pure controller medication can have immediate beneficial effects not paralleled by changes in airflow. Clinical trial registered with www.clinicaltrials.gov (NCT 01219738).

Inhaled corticosteroid treatment modulates ZNF432 gene variant's effect on bronchodilator response in asthmatics

BACKGROUND

Single nucleotide polymorphisms (SNPs) influence a patient's response to inhaled corticosteroids and β2-agonists, and the effect of treatment with inhaled corticosteroids is synergistic with the effect of β2-agonists. We hypothesized that use of inhaled corticosteroids could influence the effect of SNPs associated with a bronchodilator response.

OBJECTIVE

To assess whether, among subjects with asthma, the association of SNPs with bronchodilator response is different between those treated with inhaled corticosteroids versus those on placebo.

METHODS

A genome-wide association analysis was conducted by using 581 white subjects from the Childhood Asthma Management Program. By using data for 449,540 SNPs, we conducted a gene by environment analysis in PLINK with inhaled corticosteroid treatment as the environmental exposure and bronchodilator response as the outcome measure. We attempted to replicate the top 12 SNPs in the Leukotriene Modifier or Corticosteroid or Corticosteroid-Salmeterol Trial.

RESULTS

The combined P value for the Childhood Asthma Management Program and Leukotriene Modifier or Corticosteroid or Corticosteroid-Salmeterol Trial populations was 4.8 × 10(-8) for rs3752120, which is located in the zinc finger protein gene ZNF432 and has an unknown function.

CONCLUSIONS

Inhaled corticosteroids appear to modulate the association of bronchodilator response with variant(s) in the ZNF432 gene among adults and children with asthma.

Inhaled steroids for acute asthma following emergency department discharge

BACKGROUND

Patients with acute asthma treated in the emergency department (ED) are frequently treated with inhaled beta(2)-agonists and systemic corticosteroids after discharge. The use of inhaled corticosteroids (ICS) following discharge may also be beneficial in improving patient outcomes after acute asthma.

OBJECTIVES

To determine the effectiveness of ICS on outcomes in the treatment of acute asthma following discharge from the ED. To quantify the effectiveness of ICS therapy on acute asthma following ED discharge, when used in addition to, or as a substitute for, systemic corticosteroids.

SEARCH METHODS

Controlled clinical trials (CCTs) were identified from the Cochrane Airways Review Group register, which consists of systematic searches of EMBASE, MEDLINE and CINAHL databases supplemented by handsearching of respiratory journals and conference proceedings. In addition, primary authors and pharmaceutical companies were contacted to identify eligible studies. Bibliographies from included studies, known reviews and texts also were searched. The searches have been conducted up to September 2012

SELECTION CRITERIA

We included both randomised controlled trials (RCTs) and quasi-RCTs. Studies were included if patients were treated for acute asthma in the ED or its equivalent, and following ED discharge were treated with ICS therapy either in addition to, or as a substitute for, oral corticosteroids. Two review authors independently assessed articles for potential relevance, final inclusion and methodological quality.

DATA COLLECTION AND ANALYSIS

Data were extracted independently by two review authors, or confirmed by the study authors. Several authors and pharmaceutical companies provided unpublished data. The data were analysed using the Cochrane Review Manager software. Where appropriate, individual and pooled dichotomous outcomes were reported as odds ratios (OR) or relative risks (RR) with 95% confidence intervals (CIs). Where appropriate, individual and pooled continuous outcomes were reported as mean differences (MD) or standardized mean differences (SMD) with 95% CIs. The primary analysis employed a fixed effect model and heterogeneity is reported using I-squared (I(2)) statistics.

MAIN RESULTS

Twelve trials were eligible for inclusion. Three of these trials, involving a total of 909 patients, compared ICS plus systemic corticosteroids versus oral corticosteroid therapy alone. There was no demonstrated benefit of ICS therapy when used in addition to oral corticosteroid therapy in the trials. Relapses were reduced; however, this was not statistically significant with the addition of ICS therapy (OR 0.68; 95% CI 0.46 to 1.02; 3 studies; N = 909). In addition, no statistically significant differences were demonstrated between the two groups for relapses requiring admission, quality of life, symptom scores or adverse effects.Nine trials, involving a total of 1296 patients compared high-dose ICS therapy alone versus oral corticosteroid therapy alone after ED discharge. There were no significant differences demonstrated between ICS therapy alone versus oral corticosteroid therapy alone for relapse rates (OR 1.00; 95% CI 0.66 to 1.52; 4 studies; N = 684), admissions to hospital, or in the secondary outcomes of beta(2)-agonist use, symptoms or adverse events. However, the sample size was not adequate to exclude the possibility of either treatment being significantly inferior and people with severe asthma were excluded from these trials.

AUTHORS' CONCLUSIONS

There is insufficient evidence that ICS therapy provides additional benefit when used in combination with standard systemic corticosteroid therapy upon ED discharge for acute asthma. There is some evidence that high-dose ICS therapy alone may be as effective as oral corticosteroid therapy when used in mild asthmatics upon ED discharge; however, the confidence intervals were too wide to be confident of equal effectiveness. Further research is needed to clarify whether ICS therapy should be employed in acute asthma treatment following ED discharge. The review does not suggest any reason to stop usual treatment with ICS following ED discharge, even if a course of oral corticosteroids are prescribed.

Early use of inhaled corticosteroids in the emergency department treatment of acute asthma

BACKGROUND

Systemic corticosteroid therapy is central to the management of acute asthma. The use of inhaled corticosteroids (ICS) may also be beneficial in this setting.

OBJECTIVES

To determine the benefit of ICS for the treatment of patients with acute asthma managed in the emergency department (ED).

SEARCH METHODS

We identified controlled clinical trials from the Cochrane Airways Group specialised register of controlled trials. Bibliographies from included studies, known reviews, and texts also were searched. The latest search was September 2012.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and quasi-RCTs. Studies were included if patients presented to the ED or its equivalent with acute asthma, and were treated with ICS or placebo, in addition to standard therapy. Two review authors independently selected potentially relevant articles, and then independently selected articles for inclusion. Methodological quality was independently assessed by two review authors. There were three different types of studies that were included in this review: 1) studies comparing ICS vs. placebo, with no systemic corticosteroids given to either treatment group, 2) studies comparing ICS vs. placebo, with systemic corticosteroids given to both treatment groups, and 3) studies comparing ICS alone versus systemic corticosteroids. For the analysis, the first two types of studies were included as separate subgroups in the primary analysis (ICS vs. placebo), while the third type of study was included in the secondary analysis (ICS vs. systemic corticosteroid).

DATA COLLECTION AND ANALYSIS

Data were extracted independently by two review authors if the authors were unable to verify the validity of extracted information. Missing data were obtained from the authors or calculated from other data presented in the paper. Where appropriate, individual and pooled dichotomous outcomes were reported as odds ratios (OR) with 95% confidence intervals (CIs). Where appropriate, individual and pooled continuous outcomes were reported as mean differences (MD) or standardized mean differences (SMD) with 95% CIs. The primary analysis employed a fixed-effect model and a random-effects model was used for sensitivity analysis. Heterogeneity is reported using I-squared (I(2)) statistics.

MAIN RESULTS

Twenty trials were selected for inclusion in the primary analysis (13 paediatric, seven adult), with a total number of 1403 patients. Patients treated with ICS were less likely to be admitted to hospital (OR 0.44; 95% CI 0.31 to 0.62; 12 studies; 960 patients) and heterogeneity (I(2) = 27%) was modest. This represents a reduction from 32 to 17 hospital admissions per 100 patients treated with ICS in comparison with placebo. Subgroup analysis of hospital admissions based on concomitant systemic corticosteroid use revealed that both subgroups indicated benefit from ICS in reducing hospital admissions (ICS and systemic corticosteroid versus systemic corticosteroid: OR 0.54; 95% CI 0.36 to 0.81; 5 studies; N = 433; ICS versus placebo: OR 0.27; 95% CI 0.14 to 0.52; 7 studies; N = 527). However, there was moderate heterogeneity in the subgroup using ICS in addition to systemic steroids (I(2) = 52%). Patients receiving ICS demonstrated small, significant improvements in peak expiratory flow (PEF: MD 7%; 95% CI 3% to 11%) and forced expiratory volume in one second (FEV(1): MD 6%; 95% CI 2% to 10%) at three to four hours post treatment). Only a small number of studies reported these outcomes such that they could be included in the meta-analysis and most of the studies in this comparison did not administer systemic corticosteroids to either treatment group. There was no evidence of significant adverse effects from ICS treatment with regard to tremor or nausea and vomiting. In the secondary analysis of studies comparing ICS alone versus systemic corticosteroid alone, heterogeneity among the studies complicated pooling of data or drawing reliable conclusions.

AUTHORS' CONCLUSIONS

ICS therapy reduces hospital admissions in patients with acute asthma who are not treated with oral or intravenous corticosteroids. They may also reduce admissions when they are used in addition to systemic corticosteroids; however, the most recent evidence is conflicting. There is insufficient evidence that ICS therapy results in clinically important changes in pulmonary function or clinical scores when used in acute asthma in addition to systemic corticosteroids. Also, there is insufficient evidence that ICS therapy can be used in place of systemic corticosteroid therapy when treating acute asthma. Further research is needed to clarify the most appropriate drug dosage and delivery device, and to define which patients are most likely to benefit from ICS therapy. Use of similar measures and reporting methods of lung function, and a common, validated, clinical score would be helpful in future versions of this meta-analysis.

Acute effects of salmeterol and fluticasone propionate alone and in combination on airway blood flow in patients with asthma

BACKGROUND

The airway contains airway smooth muscle and airway vascular smooth muscle. The acute effects of inhaled long-acting β(2)-adrenergic agonists (LABAs) alone, or in combination with an inhaled glucocorticoid (ICS), on airway smooth muscle tone in asthma are known; however, to the best of our knowledge, their effect on airway vascular smooth muscle tone has not been investigated previously. The objective of this study was to investigate the immediate effects of a LABA and an ICS alone and in combination on airway blood flow (Qaw) as an index of airway vascular smooth muscle tone in patients with stable asthma.

METHODS

Fourteen subjects with moderate asthma inhaled single doses of salmeterol (50 μg), fluticasone propionate (250 μg), salmeterol/fluticasone propionate (50/250 μg), or placebo; Qaw was measured before and serially for 240 min after drug administration.

RESULTS

Mean Qaw increased after salmeterol and salmeterol/fluticasone propionate, with peaks at 60 min of 34% and 40%, respectively, and returned to baseline by 240 min after inhalation. Fluticasone propionate alone caused a transient decrease in mean Qaw. The maximal changes in Qaw, which occurred at different times, were 60% for salmeterol, 67% for salmeterol/fluticasone propionate, and -19% for fluticasone propionate (P < .05 vs placebo for all).

CONCLUSIONS

The LABA salmeterol has an acute vasodilator action on the airway of subjects with stable asthma. The addition of fluticasone propionate, which by itself causes vasoconstriction, does not attenuate the salmeterol-induced vasodilation, suggesting that fluticasone propionate potentiates the vasodilator effect of salmeterol. The vasodilation could be of clinical benefit by promoting the vascular clearance of inflammatory mediators including spasmogens from the airway.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT01231230; URL: www.clinicaltrials.gov.

Rapid nongenomic actions of inhaled corticosteroids on long-acting β(2)-agonist transport in the airway

Corticosteroids inhibit organic cation transporters (OCTs) that play an important role in drug absorption, tissue distribution and elimination. Corticosteroid sensitivity of bronchodilator trafficking in the airway tissue, however, is poorly understood. To assess the effects of inhaled corticosteroids on airway absorption and disposal mechanisms of long-acting β(2)-agonists, human airway epithelial and smooth muscle cell uptake of tritiated formoterol and salmeterol was measured in vitro. Corticosteroids caused a rapid, concentration-dependent inhibition of uptake of the cationic formoterol by airway smooth muscle cells, but not airway epithelial cells. Uptake of the non-charged lipophilic salmeterol was corticosteroid-insensitive in both cell types. In smooth muscle cells, inhaled corticosteroids inhibited formoterol uptake with a novel potency rank order: des-ciclesonide > budesonide > beclomethasone 17-monopropionate > beclomethasone dipropionate > ciclesonide > fluticasone. The inhibitory action was rapidly reversible, and was not enhanced by prolonged corticosteroid exposure or sensitive to a transcription inhibitor. Suppression of OCT3 expression using lentivirus-mediated production of shRNA reduced corticosteroid sensitivity of formoterol uptake by smooth muscle cells. Our data support a corticosteroid insensitive absorption and a corticosteroid-sensitive disposition mechanism for cationic long-acting β(2)-agonist bronchodilators in the airway. Potency rank order and other 'classical' features of anti-inflammatory effects do not apply to inhaled corticosteroids' rapid drug transport actions.

Airway endothelial dysfunction in asthma and chronic obstructive pulmonary disease: a challenge for future research

Endothelial dysfunction in the extrapulmonary circulation has been linked to cardiovascular disease. Recent investigations have revealed that in the airway circulation, cigarette smoking, chronic obstructive pulmonary disease (COPD), and asthma are also accompanied by endothelial dysfunction. Inhaled glucocorticosteroids can partially or fully restore normal endothelium-dependent vasodilation in these conditions, thereby identifying the airway endothelium as a novel therapeutic target in the treatment of airway disease. The role of the defective endothelium-dependent vasodilation in the pathophysiology in asthma and COPD is still subject to speculation. However, there appears to be an association between COPD and extrapulmonary vascular dysfunction, and the possibility exists that the use of inhaled glucocorticosteroids has a beneficial effect on cardiovascular disease in COPD as suggested by database studies showing that inhaled glucocorticosteroids reduce the incidence of nonfatal and fatal cardiovascular events in COPD.

The bronchial circulation--worth a closer look: a review of the relationship between the bronchial vasculature and airway inflammation

Until recently, the bronchial circulation has been relatively ignored in the research and clinical arenas, perhaps because of its small volume and seeming dispensability relative to the pulmonary circulation. Although the bronchial circulation only receives around 1% of the cardiac output in health, it serves functions that are critical to maintaining airway and lung function. The bronchial circulation also plays an important role in many lung and airway diseases; through its ability to increase in size, the bronchial circulation is able to provide lung parenchymal perfusion when the pulmonary circulation is compromised, and more recently the role of the bronchial circulation in the pathogenesis of inflammatory airway disease has been explored. Due to the anatomic variability and small volume of the bronchial circulation, much of the research to date has necessitated the use of animal models and invasive procedures. More recently, non-invasive techniques for measuring bronchial blood flow in the mucosal microvascular network have been developed and offer a new avenue for the study of this circulation in humans. In conjunction with molecular research, measurement of airway blood flow (Q(aw)) may help elucidate the role of the bronchial circulation in inflammatory airway disease and become a useful tool for monitoring therapy.

Rescue treatment in asthma. More than as-needed bronchodilation

International guidelines recommend the use of rapid-onset inhaled beta(2)-agonists alone for symptom relief in all asthmatic patients. However, recent clinical trials have shown that the "as-required," or PRN, use of inhaled combinations of a corticosteroid and a rapid-onset beta(2)-agonist provides clinical advantages over the traditional PRN inhaled rapid-onset beta(2)-agonists alone in patients with different degrees of asthma severity. Asthma symptoms are associated not only with bronchoconstriction but also with increased airway inflammation. Inhaled beta(2)-agonists have a rapid onset of bronchodilator action that is mainly mediated by a relaxing effect on airway smooth muscle. Inhaled corticosteroids also have rapid clinical effects that can suppress lower airway inflammation, and there is a rapid synergistic potentiation of the antiinflammatory effect of corticosteroids and of the bronchodilatory action of beta(2)-agonists when the two drugs are given simultaneously. On the basis of this emerging evidence, we propose that the current rescue use of rapid-onset inhaled beta(2)-agonists alone should now be replaced by an inhaled rapid-acting beta(2)-agonist combined with a corticosteroid as preferred PRN strategy. We conclude with a call for clinical trials aimed to test the superiority of this approach in all degrees of asthma severity in a real-world setting in addition to any of the regular treatments recommended by international guidelines. In the future it might even be possible to control asthma entirely with PRN combination inhalers without maintenance therapy, at least in patients with less severe disease.

Airway vascular reactivity and vascularisation in human chronic airway disease

Altered bronchial vascular reactivity and remodelling including angiogenesis are documented features of asthma and other chronic inflammatory airway diseases. Expansion of the bronchial vasculature under these conditions involves both functional (vasodilation, hyperperfusion, increased microvascular permeability, oedema formation, and inflammatory cell recruitment) and structural changes (tissue and vascular remodelling) in the airways. These changes in airway vascular reactivity and vascularisation have significant pathophysiological consequences, which are manifest in the clinical symptoms of airway disease. Airway vascular reactivity is regulated by a wide variety of neurotransmitters and inflammatory mediators. Similarly, multiple growth factors are implicated in airway angiogenesis, with vascular endothelial growth factor amongst the most important. Increasing attention is focused on the complex interplay between angiogenic growth factors, airway smooth muscle and the various collagen-derived fragments that exhibit anti-angiogenic properties. The balance of these dynamic influences in airway neovascularisation processes and their therapeutic implications is just beginning to be elucidated. In this review article, we provide an account of recent developments in the areas of vascular reactivity and airway angiogenesis in chronic airway diseases.