Corticosteroid sparing agents in asthma

Glucocorticoid-resistant asthma: more than meets the eye

INTRODUCTION

For decades glucocorticoids have been considered as the gold standard for the treatment of asthma. We present a case report of typical glucocorticoid-resistant asthma and current consensus in definitions of "severe refractory", "difficult" and "glucocorticoid-resistant" asthma.

METHODS

Full-text papers and abstracts were identified on the basis of a comprehensive literature search primarily in MEDLINE (1966 to June 2012) but also in the Cochrane Central Register of Controlled Trials database.

RESULTS

Glucocorticoid-resistant asthmatics are a small subset of patients who pose noteworthy diagnostic challenges while contributing disproportionately to health care costs. Recognition of various asthma phenotypes has aided in characterizing groups with severe asthma and given a better understanding of its pathophysiological process. The molecular mechanism of glucocorticoid action is complicated and several pathways have been identified to explain drug resistance, which in turn is crucial for drug development. Tobacco smoking appears to be the single most important contributor of glucocorticoid resistance. We present the emerging and promising concepts in the management of glucocorticoid-resistant asthma, which mainly include drugs targeting specific molecules, receptors, inflammatory cells or immune processes.

CONCLUSION

The challenges in making a diagnosis of glucocorticoid-resistant asthma may contribute to underestimating its prevalence and impact on patient care. Considerable progress has been made in identifying distinct phenotypes and mechanisms of glucocorticoid resistance; therefore the future of new drug development in management of asthma is promising.

Safety and efficacy of extracorporeal granulocyte and monocyte adsorption apheresis in patients with severe persistent bronchial asthma

The Adacolumn is an adsorptive-type extracorporeal device, which is filled with cellulose diacetate beads that selectively adsorb granulocytes and monocytes. Patients with severe persistent asthma experience highly variable continuous symptoms and severe exacerbations in spite of medication based on inhaled glucocorticosteroids. Granulocyte and monocyte adsorption apheresis using extracorporeal circulation through the Adacolumn was performed in nine patients with severe persistent asthma. The extracorporeal circulation through the Adacolumn was performed once a week for 5 weeks. We were able to perform this therapy without any severe adverse effects in all patients, although one patient complained of general fatigue just after the circulations. In six of the nine patients, the increase in peak expiratory flow (PEF) was more than 50 mL/min. The average increase in morning PEF was 23.3% while that in the evening PEF was 26.4% after the therapy. This therapy was not harmful for patients with severe persistent asthma. A placebo-controlled study will be desired to evaluate the efficacy of this nonpharmacological strategy accurately.

[Treatment with nebulized lidocaine in steroid-dependent asthma]

BACKGROUND

The management of glucocorticoid dependent and resistant asthma encompasses a group of problems, affecting as much control of clinical symptoms as the onset of adverse effects to prolonged use of steroids.

MATERIALS AND METHODS

Woman 52 years old, steroid dependent asthma fifteen years ago. She has important adverse effects in consequence of the use of systemic glucocorticoids. The employment of methotrexate attained decrease in the dosage of steroids temporarily. The worsening of the clinical situation and deterioration of secondary effects by use of steroids necessitated treatment with nebulized lidocaine. A 2% solution to initial dosage was administered three times daily. The maximal dosage needed was 80 mg three times daily.

RESULTS

After three months of lidocaine treatment, the patient was able to reduce oral steroids eventually discontinuing these drugs, and the effects secondary to exogenous hypercortisolism disappeared. Moreover, an improvement in clinical symptoms and quality of life was observed with stability in the pulmonary function.

CONCLUSIONS

The use of nebulized lidocaine could be useful and provide alternatives in patients with severe asthma.

Colchicine as an oral corticosteroid sparing agent for asthma

BACKGROUND

Oral corticosteroids are used as a treatment for asthma, but they are often associated with serious side effects. Colchicine is an anti-inflammatory, immuno modulating agent, which could potentially have a beneficial effect in the treatment of asthma as well as act as a steroid-sparing agent.

OBJECTIVES

To determine the effectiveness of colchicine as an oral corticosteroid sparing agent for in the treatment of chronic asthma.

SEARCH STRATEGY

We searched the Cochrane Airways Group trials register (November 2002), SIGLE (1980 to 2001) and reference lists of potential articles. We also contacted researchers in the field.

SELECTION CRITERIA

Randomised controlled trials investigating the addition of colchicine compared to placebo in stable steroid dependent asthmatics.

DATA COLLECTION AND ANALYSIS

No trials were found that met the inclusion criteria.

MAIN RESULTS

We were unable to perform any meta-analyses. Two small studies have assessed the efficacy of colchicine subsequent to inhaled steroid withdrawal and as a tapering agent in inhaled steroids. Both studies failed to detect a significant difference between colchicine and placebo.

REVIEWER'S CONCLUSIONS

No relevant trials have been published, so there is no evidence to indicate that colchicine is beneficial or otherwise in the management of steroid-dependent asthmatic patients. There is a need for well designed randomised controlled trials to be performed.

Asthma

Asthma is one of the commonest chronic diseases of affluent societies. The striking increase in prevalence of asthma over recent decades and the rarity of this disease in less affluent populations confirms the importance of environmental factors in the cause of asthma--although which environmental factors are responsible is still not clear. Family studies show that genetic factors are also important in determining individual susceptibility to asthma, with results of genetic studies suggesting that there are many genes with moderate effects rather than a few major genes. Asthmatic airways show inflammation and remodelling, with CD4+ helper cells, mast cells, and eosinophils characterising the inflammatory response. Inhaled corticosteroids remain the cornerstone of treatment with the addition of long-acting beta agonists as the next step if symptoms continue. Leukotriene antagonists, the only new drugs to reach the market in the past decade, have modest effects. However, a better understanding of the mechanisms underlying asthma and the genetic and environmental factors that predispose individuals to asthma should lead to better preventative strategies and new therapeutic approaches.

Dapsone as an oral corticosteroid sparing agent for asthma

BACKGROUND

Oral corticosteroids are used as a treatment for asthma, however they are often associated with serious side effects. Dapsone is a sulfone with anti-inflammatory properties, therefore it may have a beneficial effect in the treatment of asthma and act as a corticosteroid-sparing agent.

OBJECTIVES

The objective of this review is to assess the safety and efficacy of adding dapsone to oral corticosteroids in adults with stable asthma who are dependent on oral corticosteroids with the intention of eventually minimizing or eliminating the use of these steroids.

SEARCH STRATEGY

The Cochrane Airways group trials register and reference lists of potential articles were searched.

SELECTION CRITERIA

Randomised controlled trials investigating the addition of dapsone compared to placebo in stable corticosteroid dependent asthmatics.

DATA COLLECTION AND ANALYSIS

No trials were found that met the selection criteria.

MAIN RESULTS

No meta-analyses could be performed.

REVIEWER'S CONCLUSIONS

No randomised controlled trials have been published, so there is no reliable evidence to show whether dapsone is beneficial or otherwise in the management of steroid-dependent asthmatic patients. There is a need for well designed randomised controlled trials to be performed. These must be carried out double-blind, since oral corticosteroid reduction requires a judgement on the part of the physician, who may be open to bias if the treatment allocation is known.

How to manage difficult asthma cases. An action plan for physicians and patients

Patients with difficult-to-manage asthma represent one of the greatest challenges in primary care practice. Because these patients are at risk for life-threatening attacks, close monitoring is essential to ensure compliance and to control attacks or medication side effects. In this article, Dr Hunt discusses the many aspects of management, including assessment, identification of triggers, treatment planning, and patient and family education. An "action plan" that outlines the management program is described.

Effect of single doses of inhaled lignocaine on FEV1 and bronchial reactivity in asthma

Inhaled lignocaine appeared to have considerable steroid sparing properties in an uncontrolled trial in 20 patients with oral-steroid-dependent asthma. Since it can also cause bronchoconstriction, safety needs to be studied under controlled conditions. We have performed a randomized, double-blind, placebo-controlled study in 20 patients with mild to moderate asthma to determine the effects of single doses of inhaled lignocaine 40 and 160 mg compared to saline. Saline and lignocaine 40 and 160 mg caused an initial fall in FEV1, mean maximum change being 0.13, 0.19 and 0.231 respectively with no significant difference between treatments (P = 0.2). There was no fall in FEV1 following salbutamol pretreatment and lignocaine had no significant effect on heart rate or blood pressure or on bronchial reactivity to methacholine carried out at 90 min after inhalation. These results show that single doses of inhaled lignocaine are well tolerated in subjects with mild to moderate asthma and that any tendency to bronchoconstriction can be prevented with salbutamol pretreatment.

Low-dose methotrexate spares steroid usage in steroid-dependent asthmatic patients: a meta-analysis

STUDY OBJECTIVES

To determine if treatment with low-dose methotrexate spares oral steroids in adult, steroid-dependent, asthmatic patients.

DESIGN

Articles identified by computer search were excluded if they (1) did not contain original data relating to the primary question, (2) had no controls, or (3) described subjects younger than 18 years of age.

MEASUREMENTS

From each article, the following was abstracted: reference citation; type of control; whether study incorporated a run-in period in which the baseline level of prednisone was reduced to the lowest possible dose; dosage and length of methotrexate therapy; baseline dosage; and type of steroid. Also, the following was determined during both placebo and methotrexate arms of each study: steroid dosage, FEV1, serious side effects, and alteration in level of serum aspartate aminotransferase.

RESULTS

Eleven eligible studies were identified. Methotrexate treatment resulted in a decrease in prednisone or prednisolone usage by an average of 4.37 mg/d or 23.7% of the initial dosage. The summary effect size in standard deviations (SDs) was -0.53 (95% confidence interval=-0.29 to -0.77). Subgroup analysis showed that patients treated with prolonged (6-month) therapy with methotrexate, those with low long-term usage of steroids (< or = 20 mg/d), and those whose study design incorporated a run-in period, tended to have the greatest steroid-sparing effects with methotrexate.

CONCLUSIONS

Low-dose methotrexate has a significant steroid-sparing effect in steroid-dependent asthmatic patients. The greatest effect was evident in patients in whom an effort was made to reduce baseline steroid dosage and in whom methotrexate was used for 24 weeks.

Pharmacotherapy of Asthma

The approach to asthma therapy has changed from an emphasis on bronchodilation to an emphasis on anti-inflammatory medications. New guidelines from the National Asthma Education and Prevention Program Expert Panel II were released in February 1997 and emphasize that inhaled corticosteroids are the cornerstone of pharmacotherapy. New inhaled corticosteroids and new delivery methods have been introduced which have significant advantages over older products. Pharmacological innovations such as the leukotriene modifiers represent continued research to influence the inflammatory response. Agents or therapies which can decrease the daily dose of systemic corticosteroids continue to be investigated in continued efforts to reduce the side effects and adverse reactions associated with systemic corticosteroid therapy.

Asthma therapy with aerosols: clinical relevance for the next decade

Inhaled therapy is the mainstay of modern asthma management, as this optimizes the therapeutic ratio. Short-acting beta 2-agonists are the most effective bronchodilators and when given by inhalation give rapid relief of symptoms, without adverse effects, although there are concerns about overuse of these drugs. Inhaled long-acting beta 2-agonists are useful in some patients. Inhaled anticholinergics are particularly useful in patients with COPD and in the future long-acting drugs, such as tiotropium bromide, will be available. Inhaled glucocorticoids are the most effective therapy in controlling chronic asthma symptoms, and systemic effects are not a problem in the vast majority of patients. Improved inhalation devices and steroids with reduced oral bioavailability have resulted in reduced systemic side effects, which now arise largely from absorption from the lungs. In the future it is likely that new classes of drug will be developed, but whether they will be used by inhalation or given by mouth will depend on the frequency of side effects and the mode of action of the drugs. There are likely to be several improvements in inhaler delivery systems, so that the inhaled route will remain predominant for many years to come.

A risk-benefit assessment of methotrexate in corticosteroid-dependent asthma

Methotrexate is a folic acid antagonist with proven anti-inflammatory properties. This originally led to its use in the therapy of some rheumatic and dermatological inflammatory disorders and, since the early 1980s, as a corticosteroid-sparing agent in the therapy of bronchial asthma. Although the exact anti-inflammatory mechanism is not known, it appears that in some patients with severe corticosteroid-dependent bronchial asthma, a reduction of at least 50% in the maintenance corticosteroid dosage can be achieved. Controversies regarding methotrexate efficacy may be a result of the small size and heterogeneity of the patient populations studied and the variable definition of corticosteroid "dependence'. Although the potential for serious short and long term adverse effects resulting from methotrexate therapy cannot be ignored, overall, methotrexate appears to be well tolerated at low dosages. Hepatic and pulmonary toxicity are the main adverse effects of concern. The "lesser evil' approach is logical, but it is imperative to administer the drug for at least 3 months to adequately assess its efficacy in a specific patient.

Outpatient asthma management

Asthma is an inflammatory disease. Educated asthmatics can be involved in self-managements strategies that focus on prevention and treatment of airway inflammation using environmental control and inhaled corticosteroids as the cornerstones of therapy. It is hoped that such an approach will reduce asthma morbidity and mortality rates.