Acute asthma. Single dose oral steroids in paediatric community clinics

Evaluating the effectiveness of systemic corticosteroids to mitigate relapse in children assessed and treated for acute asthma: A network meta-analysis

OBJECTIVE

The objective of this systematic review was to explore the effectiveness of various systemic corticosteroid (SCS) regimens to mitigate relapse in children with asthma discharged from an acute care setting.

DATA SOURCES

Medline, EMBASE, Global Health, International Pharmaceutical Abstracts, EMB ALL, CINAHL, SCOPUS, Proquest Dissertations and Theses Global, and LILACS were searched using controlled vocabulary and key words. Additional citations were searched via clinical trial registries, Google Scholar, bibliographies, a SCOPUS forward search of a sentinel paper, and hand searching conference abstracts.

STUDY SELECTION

No limitations based on language, publication status, or year of publication were applied. Two independent reviewers searched to identify randomized controlled trials comparing the effectiveness of SCS regimens to prevent relapse in children following treatment for acute asthma.

RESULTS

Fifteen studies were included. In 3 studies comparing SCS to placebo, asthma relapse was significantly reduced (RR = 0.10; 95% CI: 0.01, 0.77; I² = 0%). A network analysis identified a significant reduction in relapse in children treated with intramuscular corticosteroids (OR = 0.038; 95% CrI: 0.001, 0.397), short-course oral prednisone (OR = 0.054; 95% CrI: 0.002, 0.451), and oral dexamethasone (OR = 0.071; 95% CrI: 0.002, 0.733) compared to placebo.

CONCLUSION

This review found evidence that SCS reduces relapse in children following treatment for acute asthma, albeit based on a limited number of studies. Additional studies are required to assess the differential effect of SCS doses and treatment duration to prevent relapse in children following discharge for acute asthma.

Rhinovirus and the developing lung

Human rhinovirus (HRV) infections are now widely accepted as the commonest cause of acute respiratory illnesses (ARIs) in children. Advanced PCR techniques have enabled HRV infections to be identified as causative agents in most common ARIs in childhood including bronchiolitis, acute asthma, pneumonia and croup. However, the long-term implications of rhinovirus infections are less clear. The aim of this review is to examine the relationship between rhinovirus infections and disorders of the lower airways in childhood.

Corticosteroids in respiratory diseases in children

We review recent advances in the use of corticosteroids (CS) in pediatric lung disease. CS are frequently used, systemically or by inhalation. Their mechanisms of action in pulmonary diseases are ill defined. CS exert direct inhibitory effects on many inflammatory cells through genomic mechanisms. There is a time lag before clinical response, and the washout of effects is also prolonged. Prompt relief in some conditions, such as croup, may be related to airway mucosal vasoconstriction through a nongenomic mechanism. CS have proven beneficial roles in the treatment of asthma, croup, allergic bronchopulmonary aspergillosis, and subglottic hemangioma. In some conditions, such as bronchiolitis, cystic fibrosis, and bronchopulmonary dysplasia, their use is controversial and is not recommended routinely. In other conditions, such as tuberculosis, interstitial lung disease, acute lung aspiration, and acute respiratory distress syndrome, CS are often used empirically despite the lack of clear evidence of their benefit. New drug regimens, including the more flexible use of inhaled corticosteroids and long-acting β-agonists in asthma, the lack of efficacy of oral corticosteroids in preschool children with acute wheeze, the severe complications of systemic dexamethasone used to prevent bronchopulmonary dysplasia and thus more restricted use, and the beneficial effect of pulse high-dose intravenous methylprednisolone in patients with allergic bronchopulmonary aspergillosis or cystic fibrosis are among the major recent developments. There is concern about adverse effects, especially growth and adrenal suppression, induced by systemic CS in children. These have been reduced, but not eliminated, with the use of the inhaled route. The benefits must be weighed against the potential detrimental effects.

Preventing emergency department visits and hospitalizations for asthma by use of oral corticosteroids at home: are we adhering to national guidelines?

BACKGROUND

Oral corticosteroids (OCS) in the home management of asthma exacerbations have been recommended in the NIH/NHLBI guidelines since 1991. As a routine component of written action plans, OCS treatment at home is associated with reduced emergency department (ED) visits and hospitalizations as well as decreased mortality.

METHODS

A literature search of English language journals from 1991 to 2009 was performed using several databases, including PubMed, EMBASE, and SCOPUS. We assessed studies that evaluated adherence to national guidelines for home management of asthma exacerbations.

RESULTS

Our review of the literature found that several studies reveal that a small percentage (<3-26%) of patients are receiving OCS at home to manage asthma exacerbations prior to an ED visit. Additional studies were found showing very low use of written action plans, strongly suggesting lack of OCS for home management of asthma exacerbations.

CONCLUSIONS

Despite evidence of reduced ED visits and hospitalizations and the recommendations of national and international guidelines, the home use of OCS in managing asthma exacerbations remains unacceptably low. New strategies are needed to ensure home use of OCS as part of written action plans to prevent ED visits and hospitalizations for asthma exacerbations.

Controversies in the management of preschool viral wheeze

The clinical diagnosis of asthma represents several putative wheeze phenotypes, each associated with a unique cluster of risk factors, underlying inflammation, and response to therapy. In school-age children, the 'classical' atopic asthma phenotype predominates. By contrast, asthma in children aged between 1 and 5 years is frequently characterised by transient episodes of wheeze trigged by viral colds, with few or no interval symptoms (preschool viral wheeze). This phenotype has a different cluster of risk factors from atopic asthma and thus might not respond to asthma therapies of proven efficacy in older children. The objective of this review is to look at the current evidence in the management of 'preschool viral wheeze'.

Written action plans for asthma in children

BACKGROUND

While all asthma consensus statements recommend the use of written action plan (WAP) as a central part of asthma management, a recent systematic review of randomised trials highlighted the paucity of trials where the only difference between groups was the provision or not of a written action plan.

OBJECTIVES

The objectives of this review were firstly to evaluate the independent effect of providing versus not providing a written action plan in children and adolescents with asthma, and secondly to compare the effect of different written action plans.

SEARCH STRATEGY

We searched the Cochrane Airways Group Specialised Register (November 2004), which is derived from searches of CENTRAL, MEDLINE, EMBASE, CINAHL, as well as handsearched respiratory journals, and meeting abstracts. We also searched bibliographies of included studies and identified review articles.

SELECTION CRITERIA

Randomised controlled trials were included if they compared a written action plan with no written action plan, or different written action plans with each other.

DATA COLLECTION AND ANALYSIS

Two authors independently selected the trials, assessed trial quality and extracted the data. Study authors were contacted for additional information.

MAIN RESULTS

Four trials (three RCTs and one quasi-RCT) involving 355 children were included. Children using symptom-based WAPs had lower risk of exacerbations which required an acute care visit (N = 5; RR 0.73; 95% CI 0.55 to 0.99). The number needed to treat to prevent one acute care visit was 9 (95% CI 5 to 138). Symptom monitoring was preferred over peak flow monitoring by children (N = 2; RR 1.21; 95% CI 1.00 to 1.46), but parents showed no preference (N = 2; RR 0.96; 95% CI 0.18 to 2.11). Children assigned to peak flow-based action plans reduced by 1/2 day the number of symptomatic days per week (N = 2; mean difference: 0.45 days/week; 95% CI 0.04 to 0.26). There were no significant group differences in the rate of exacerbation requiring oral steroids or admission, school absenteeism, lung function, symptom score, quality of life, and withdrawals.

AUTHORS' CONCLUSIONS

The evidence suggests that symptom-based WAP are superior to peak flow WAP for preventing acute care visits although there is insufficient data to firmly conclude whether the observed superiority is conferred by greater adherence to the monitoring strategy, earlier identification of onset of deteriorations, higher threshold for presentation to acute care settings, or the specific treatment recommendations.

Parent-initiated oral corticosteroid therapy for intermittent wheezing illnesses in children

BACKGROUND

Intermittent wheezing illnesses, which include viral associated wheeze and asthma, are amongst the most common reasons for children to present urgently to a doctor. Whether parents should commence oral corticosteroids (OCS) for an episode of acute wheeze in their child without waiting for a medical review is an important question, as the potential benefits of early oral corticosteroid intervention have to be weighed against the potential adverse effects of treatment.

OBJECTIVES

The objectives were to assess the benefits and harmful effects of parent-initiated OCS, in the management of intermittent wheezing illnesses in children, based on the results of randomised clinical trials.

SEARCH STRATEGY

The Cochrane Airways Group Specialised Register, The Cochrane Controlled Trials Register (CENTRAL), MEDLINE, EMBASE, LILACS, Web of Science and Dissertation Abstracts were combined (all searched November 2005). Manufacturers and researchers in the field were also contacted.

SELECTION CRITERIA

Only randomised clinical trials studying patients aged between one and eighteen years old, with an intermittent wheezing illness (asthma, viral wheeze, preschool viral wheeze) were included. Interventions encompassed OCS at any dose or duration versus placebo or other drug combination. The trials could be unpublished or published and no language limitations were applied.

DATA COLLECTION AND ANALYSIS

Two reviewers independently selected trials for inclusion, assessed trial quality and extracted the data. The statistical package (RevMan 4.2) provided by the Cochrane Collaboration was used.

MAIN RESULTS

From 572 original citations, a total of 2 randomised clinical trials (303 randomised participants) were included. The quality of the included trials was high; however, marked clinical heterogeneity precluded a meta-analysis. The two trials did not find evidence that parent-initiated OCS are associated with a benefit in terms of hospital admissions, unscheduled medical reviews, symptoms scores, bronchodilator use, parent and patient impressions, physician assessment, or days lost from work or school. Adverse outcomes were inadequately documented.

AUTHORS' CONCLUSIONS

Limited current evidence is available and it is inconclusive regarding the benefit from parent-initiated OCS in the treatment of intermittent wheezing illnesses in children. Widespread use of this strategy cannot be recommended until the benefits and harms can be clarified further.

Treatment of childhood asthma: how do the available options compare?

The National Asthma Council of Australia suggests that "the aim of preventive therapy should be to enable patients to enjoy a normal life (comparable with that of non-asthmatic children), with the least amount of medication and at minimal risk of adverse events. The level of maintenance therapy should be determined by symptom control and lung function in the interval periods." The British Thoracic Society/Scottish Intercollegiate Guidelines Network states that the aims of the pharmacological treatment of asthma should be to control symptoms, prevent exacerbations and achieve the best possible lung function with minimal adverse effects. We have used the current published international guidelines to highlight the international differences in management recommendations, and compared the possible pharmacological options with a focus on the above ideals. Cromones have been used for many years in childhood asthma. Most evidence suggests they now have little role. Regarding inhaled corticosteroids (ICS), beclomethasone and budesonide are essentially similar in their efficacy. Fluticasone propionate is equally as effective at one-half the equivalent dose of budesonide or beclomethasone. Adverse effects are rare in dosages <400 microg/day of budesonide and beclomethasone or <200 microg/day of fluticasone propionate, but may occur in individual patients. Relevant clinical adverse effects are rare and pharmacological systemic effects are less noticeable with budesonide and fluticasone propionate than with beclomethasone, but data are conflicting. Long-acting beta2-adrenoceptor agonists (beta2-agonists) are recommended once low-dose ICS have failed to control symptoms. The main pharmacological difference between the agents is that formoterol is a full beta2-adrenergic agonist, whereas salmeterol is a partial agonist at the beta2-adrenoceptor and has a unique pharmacological action. The main clinical distinction between these two agents is that their onset of bronchodilation differs. Bronchodilation begins at about 3 minutes after inhalation of formoterol, which is similar to the short-acting agents, whereas salmeterol has a much slower onset of action at about 15-30 minutes. The many in vitro differences between the two drugs are probably not clinically relevant. There are no comparative pediatric data on the leukotriene modifiers to make clear recommendations.

Oral prednisolone in the acute management of children age 6 to 35 months with viral respiratory infection-induced lower airway disease: a randomized, placebo-controlled trial

OBJECTIVE

To investigate the efficacy of oral prednisolone in virally induced respiratory distress. Study design Randomized, double-blind, placebo-controlled trial involving 230 children age 6 to 35 months in the emergency department. Each patient received either oral prednisolone (2 mg/kg/d) or placebo for 3 days.

RESULTS

The hospitalization rates were similar between the two groups. For admitted children (n=123), the median length of stay was 1 day shorter in the prednisolone group (2 vs 3 days, P=.060). The proportion of children requiring >or=3 days of hospitalization was 47.5% in the prednisolone group and 67.7% in the placebo group (P=.023). There was less need for additional asthma medication (18.0% vs 37.1%, P=.018) in the prednisolone group. The median duration of symptoms of respiratory distress was 1 day in the prednisolone group versus 2 days in the placebo group both among the hospitalized (P<.001) and nonhospitalized children (P=.006).

CONCLUSION

A 3-day course of oral prednisolone effectively reduced disease severity, length of hospital stay, and the duration of symptoms among children 6 to 35 months old with virally induced respiratory distress.

Treating exacerbations of asthma in children: the role of systemic corticosteroids

OBJECTIVE

To review the use of systemic corticosteroids to treat recurrent, acute asthma episodes in children, with a focus on the role of oral corticosteroids.

METHODS

A comprehensive review of the literature was performed using the Medline database (January 1966-October 2002) and the Embase database (January 1980-August 2002).

RESULTS

The significant findings of 17 selected, controlled clinical trials of oral corticosteroids (OCSs) for acute exacerbations of asthma in children, compared with placebo or with other formulations of corticosteroids, can be summarized as follows: 1) OCSs are effective for the outpatient treatment of acute asthma, 2) pulmonary function tests may not be the best means of assessing the efficacy of OCSs for acute asthma, 3) early administration of OCSs for acute asthma reduces hospitalizations, 4) the critical factor for a positive outcome is early administration of the corticosteroid, and 5) OCSs are preferred for the outpatient treatment of acute asthma.

CONCLUSIONS

Early treatment of acute asthma symptoms with OCSs in children with a pattern of recurrent acute asthma may decrease the severity of acute asthma episodes and reduce the likelihood of subsequent relapses. Attention should be given to identifying these children and standardizing a treatment approach based on accepted, consistent definitions of what constitutes an asthma exacerbation and recurrence. A suggested protocol is described.

Corticosteroids for hospitalised children with acute asthma

BACKGROUND

Systemic corticosteroids are used routinely in the management of children with severe acute asthma. There is a lack of consensus regarding the agent, dose and route of corticosteroid administration.

OBJECTIVES

To determine the benefit of systemic corticosteroids (oral, intravenous, or intramuscular) compared to placebo and inhaled steroids in acute paediatric asthma.

SEARCH STRATEGY

All controlled trials were identified from the Cochrane Airways Review Group Register, hand searching of respiratory journals, reference lists and contacts with experts and pharmaceutical companies.

SELECTION CRITERIA

Studies were included if they described a randomised controlled trial (RCT) involving children aged 1-18 years with severe acute asthma who received oral, inhaled, intravenous or intramuscular corticosteroids. Only studies in which patients required hospital admission were included.

DATA COLLECTION AND ANALYSIS

Two reviewers using a standard form extracted all data. All data, numeric calculations and graphic extrapolations were independently confirmed.

MAIN RESULTS

Seven trials were included with a total of 426 children studied (274 with oral prednisone vs. placebo, 106 with intravenous steroids vs placebo and 46 with nebulised budesonide vs prednisolone). A significant number of steroid treated children were discharged early after admission (>4 hours) with an OR of 7.00 (95% CI: 2.98 to 16.45) and NNT of 3 (95%CI: 2 to 8). The length of stay was shorter in the steroid groups with a WMD of -8.75 hours (95% CI: -19.23 to 1.74). There were no significant differences between groups in pulmonary function or oxygen saturation measurements. Children treated with steroids in hospital were less likely to relapse within one to three months with OR 0.19 (95%CI: 0.07 to 0.55) and NNT of 3 (95%CI: 2 to 7). The single small study that compared nebulised budesonide to oral prednisone failed to demonstrate equivalence or a difference between each therapy.

REVIEWER'S CONCLUSIONS

Systemic corticosteroids produce some improvements for children admitted to hospital with acute asthma. The benefits may include earlier discharge and fewer relapses. Inhaled or nebulised corticosteroids cannot be recommended as equivalent to systemic steroids at this time. Further studies examining differing doses and routes of administration for corticosteroids will clarify the optimal therapy.

Choosing therapy for childhood asthma

Inhaled corticosteroids remain the primary long-term treatment for controlling childhood asthma. Sodium cromoglycate (cromolyn sodium) and nedocromil sodium are both well tolerated, but usually less effective, alternatives to corticosteroids. Long-acting beta(2)-agonists (beta(2)-adrenoceptor agonists) may be useful adjuncts in patients already receiving inhaled corticosteroids who require frequent use of short-acting bronchodilators or experience nocturnal exacerbations (i.e. overall asthma control suboptimal). Theophylline has bronchodilator and anti-inflammatory effects and may also be used as an adjunct to inhaled corticosteroids. Leukotriene receptor antagonists are now an alternative as monotherapy in young children with mild persistent asthma, or as adjunctive therapy with inhaled corticosteroids as well. Short-acting inhaled beta(2)-agonists or other short-acting bronchodilators should be used as needed for acute episodes. For inhaled delivery, metered-dose inhalers with spacer devices (holding chambers) may be used as the delivery system in many patients, but the choice of inhalation method must be individualised, based largely on patient acceptance and compliance. Systemic corticosteroids may be used to gain prompt control when initiating long-term therapy in patients with severe, persistent asthma that does not respond to inhaled medication or in patients who are unable to take inhaled medication. The anti-immunoglobulin E antibody, omalizumab, is a novel therapy that attacks a fundamental immunopathological process of asthma and has shown promising results in several clinical trials.

Treatment of acute asthma. A new look at the old and at the new

beta-Agonists remain the mainstay of therapy for acute asthma and, for most patients, standard doses are acceptable. Although the onset of action of systemic steroids is still not clear, steroids promote recovery and should be given to patients with acute illness. Intravenous magnesium sulfate appears to improve pulmonary function in the most severely ill patients but is not useful in patients with more moderate episodes. Ipratropium bromide is a weak bronchodilator that still needs to be tested as an adjunct to standard treatment regimens before its role in adults with asthma can be determined; given its ease of use and favorable safety profile it could be considered for patients with more severe acute illness. Aminophylline has not been found by most studies to improve outcomes and the narrow therapeutic range and unfavorable safety profile relegate it to a last-line agent or no use at all. Helium-oxygen mixtures currently have no role in moderately ill patients but have a theoretical advantage as a temporizing measure in severely ill patients. Drugs used in the management of chronic asthma, such as inhaled steroids and leukotriene-modifying agents, are making their way into the acute treatment arena, and other newly developed specific mediator inhibitors or blockers deserve attention. The use of isomers of beta-agonists is another area that is attracting attention and study. Systemic steroids are used to prevent relapse after emergency department discharge and the addition of other agents such as leukotriene-modifying agents or inhaled steroids may further prevent the need for urgent visits or hospitalization. The search for optimal treatment strategies for acutely ill patients is challenging and exciting and, with more attention and resources being devoted to this area, newer treatments will be found that will eventually have a greater impact on the high morbidity associated with acute asthma.

The role of corticosteroids in respiratory diseases of children

Glucocorticosteroids are potent anti-inflammatory agents and have an important role in a variety of respiratory diseases. Although their exact mode of action is unknown, it is thought that they exert their effects by binding to cytoplasmic glucocorticoid receptors. In certain conditions, such as asthma, the value of steroids cannot be questioned, and inhaled steroids have revolutionized management. In other situations, such as interstitial lung disease, the true role of steroids is still to be defined. In the management of diseases such as tuberculosis, the use of steroids is solely based on anecdotal experience.