Managing wheeze in preschool children

Vitamin D Level and Immune Modulation in Children with Recurrent Wheezing

INTRODUCTION AND AIM

A direct causal relationship between vitamin D (vit D) deficiency and recurrent wheezing has not been proven. The present study investigated the role of vit D in enhancing the risk of asthma or recurrent wheezing by modifying the intensity of the inflammatory process.

MATERIAL AND METHOD

Forty children with wheezing presenting at the emergency service and sixteen healthy control subjects were included in the study. Children with wheezing were either in the first episode (20) or with recurrent wheezing (20). Children with chronic diseases, and other conditions that present with acute wheezing or that might influence the vit D level, were excluded. Blood samples were taken at presentation and 3-6 months later, to evaluate the serum levels of total IgE, vit D, IL-10 and IL-31. Statistical analysis was performed using the SPSS 25 program, with a significance level of p < 0.05.

RESULTS AND CONCLUSION

The vit D level was lower in patients with recurrent wheezing compared with those with a single episode and with the control group, and this increased with time. IL-10 was significantly higher in children with wheezing than in the control group, with the highest values in those with an acute episode of wheezing. IL-31 was higher in children with recurrent wheezing than in those with a first episode only at the initial point, while at the final time point it was lower. Low levels of vit D appear to be detected more frequently in recurrent wheezing than in simple wheezing. Immune modulation, as measured by Th2 status reflected by IL-10 and IL-31 levels, appears to depend on the wheezing phenotype and on the general health status.

Enigma variations: The multi-faceted problems of pre-school wheeze

Numerous publications on wheezing disorders in children younger than 6 years have appeared in the medical literature over the last decades with the aim of shedding light on the mechanistic pathways (endotypes) and treatment. Nevertheless, there is yet no consensus as to the appropriate way to manage preschool wheeze mainly because of the lack of a clear definition of "preschool asthma" and the paucity of scientific evidence concerning its underlying endotypes. A symptom-based approach is inadequate since the human airway can respond to external stimuli with a limited range of symptoms and signs, including cough and wheeze, and these manifestations represent the final expression of many clinical entities with potentially different pathophysiologies requiring different individualized treatments. Hence, new studies challenge the symptom-based approach and promote the importance of managing the wheezy child based on the "airway phenotype." This will enable the clinician to identify not only the child with a serious underlying pathology (e.g., a structural airway disorder or immunodeficiency) who is in need of prompt and specific treatment but also increase the specificity of treatment for the child with symptoms suggestive of an "asthma" syndrome. In the latter case, focus should be given to the identification of treatable traits. This review summarizes the current understanding in management of preschool wheezing and highlights the unmet need for further research.

Can vitamin D3 supplementation reduce the time to severe asthma exacerbations in children with asthma?

Vitamin D deficiency in children needs to be treated irrespective of asthma benefits. The VDKA trial showed that vitamin D supplementation in school-age asthmatic children with vitamin D insufficiency did not improve asthma control. https://bit.ly/2UF3j61.

The Role of Interferons in Driving Susceptibility to Asthma Following Bronchiolitis: Controversies and Research Gaps

Bronchiolitis is the most common cause of hospitalization in infancy and is associated with a higher risk for the development of childhood asthma. However, not all children hospitalized with bronchiolitis will develop asthma. The mechanisms underlying asthma development following bronchiolitis hospitalization are complex. Immune responses to respiratory viruses may underlie both bronchiolitis severity and long-term sequela (such as asthma). Interferons (IFNs) are important components of innate immune responses to respiratory viruses and could influence both asthma development and asthma exacerbations. However, the nature of the relationship between interferon production and wheezing illnesses is controversial. For example, low peripheral blood IFN responses at birth have been linked with recurrent wheeze and asthma development. In contrast, there is evidence that severe illnesses (e.g., hospitalization for bronchiolitis) are associated with increased IFN responses during acute infection (bronchiolitis hospitalization) and a higher risk for subsequent asthma diagnosis. Furthermore, mechanistic studies suggest that bronchial epithelial cells from asthmatic children have impaired IFN responses to respiratory viruses, which may enable increased viral replication followed by exaggerated secondary IFN responses. This review aims to discuss controversies around the role of IFNs as drivers of susceptibility to asthma development following bronchiolitis hospitalization. Past evidence from both mechanistic and cohort studies are discussed. We will highlight knowledge gaps that can inform future research study design.

Things We Do for No Reason: Systemic Corticosteroids for Wheezing in Preschool-Aged Children

Wheezing is common in preschool-aged children (ages 2-5 years), with up to half in this age group having experienced a wheezing episode and up to one-third, recurrent wheezing.1,2 Young children with wheezing require ED visits and hospitalizations at much higher rates than older children and adults.3 Several studies have also demonstrated that children in this age group have higher rates of SCS prescriptions compared with older children.4,5 Despite the high prevalence of wheezing in this age group, there is great heterogeneity in the etiology and clinical progression of early childhood wheezing, with up to six described phenotypes each with varying levels of association with the development of asthma.6 Given the high frequency of asthma, preschool-aged children admitted with wheezing are often treated with SCS, as this is the standard of care for an acute asthma exacerbation.7

Children with Asthma Have Fixed Airway Obstruction through Childhood Unaffected by Exacerbations

BACKGROUND

Children with asthma may have a disease course with or without exacerbations, but the relationship between exacerbations and lung function development is poorly understood.

OBJECTIVE

To compare lung function trajectories from birth till adolescence in asthmatic children with and without exacerbations.

METHODS

Children with asthma from the Copenhagen Prospective Studies on Asthma in Childhood₂₀₀₀ (COPSAC₂₀₀₀) birth cohort had lung function and bronchial reactivity assessed repeatedly from 1 month to 13 years. Exacerbations were diagnosed at the COPSAC clinic defined as symptoms requiring hospitalization, oral or high-dose inhaled corticosteroid treatment. Mixed models were applied to analyze lung function trajectories.

RESULTS

Children with asthma with exacerbations (N = 50) had a trajectory of increased, fixed airway obstruction compared with children without exacerbations (N = 47): z-score difference in airway resistance (sRaw_z) (95% confidence interval [CI]): +0.34 (+0.03; +0.66), P = .03, and maximal mid-expiratory flow (MMEF_z): -0.41 (-0.69; -0.13), P = .004, but no differences in forced expiratory volume (FEV_z): -0.14 (-0.41; +0.13), P = .29, or bronchial reactivity to methacholine (PD_z): +0.08 (-0.26; +0.42), P = .65. This did not change comparing lung function trajectories before and after exacerbations: z-score difference (95% CI) sRaw_z: -0.04 (-0.35; 0.27), P = .80; MMEF_z: 0.01 (-0.02; 0.04), P = .55; FEV_z: 0.02 (-0.02; 0.05), P = .42; and PD_z: -0.01 (-0.06; 0.05), P = .88.

CONCLUSION

Children with asthma with exacerbations compared with children with asthma without exacerbations are characterized by increased airway obstruction since infancy through childhood. The airway obstruction is a fixed trajectory without progression due to exacerbations, suggesting that exacerbations are a consequence rather than a cause of diminished airway caliber in childhood.

A risk factor for early wheezing in infants: rapid weight gain

Background

The aim of this study was to investigate the correlation between rapid weight gain and early wheezing.

Methods

This study screened 701 infants with lower respiratory tract infection who were no more than 4 months from Jan 1st to Dec 31st in 2018. According to weight-for-age Z-value (WAZ), these infants were divided into the considerably slow weight gain group (group I), the normal weight gain group (group II) and the excessively rapid weight gain group (group III), respectively. The clinical characteristics, weight growth speeds and serum lipid levels were analyzed, and multivariable Logistic model was conducted to select significant variables.

Results

Our results showed that male (OR = 1.841, 95%CI: 1.233–2.751), family wheezing (OR = 5.118, 95%CI: 2.118–12.365), age (OR = 1.273, 95%CI: 1.155–1.403), eczema (OR = 2.769, 95%CI: 1.793–4.275), respiratory syncytial virus (RSV) infection (OR = 1.790, 95%CI: 1.230–2.604), birth weight (OR = 1.746, 95%CI: 1.110–2.746) and total cholesterol (TC) (OR = 1.027, 95%CI: 1.019–1.036) and ΔWAZ (OR = 1.182, 95%CI: 1.022–1.368) were associated with early wheezing. Results indicated that serum TC (P = 0.018) and ΔWAZ (P = 0.023) were positive correlation with wheezing days.

Conclusion

Besides male, family wheezing, age, eczema, RSV infection, birth weight and TC, the rapid weight growth as a risk factor should be concerned in the early wheezing infants.

Episodic viral wheeze and multiple-trigger wheeze in preschool children are neither distinct nor constant patterns. A prospective multicenter cohort study in secondary care

OBJECTIVES

To evaluate whether episodic viral wheeze (EVW) and multiple-trigger wheeze (MTW) are clinically distinguishable and stable preschool wheezing phenotypes.

METHODS

Children of age 1 to 4 year with recurrent, pediatrician-confirmed wheeze were recruited from secondary care; 189 were included. Respiratory and viral upper respiratory tract infection (URTI) symptoms were recorded weekly by parents in an electronic diary during 12 months. Every 3 months, diary-based symptoms were classified as EVW or MTW and compared to phenotypes assigned by pediatricians based on clinical history. We collected nasal samples for respiratory virus PCR during URTI, respiratory symptoms and in absence of symptoms.

RESULTS

Of 660 3-month periods, the diary-based phenotype was EVW in 11%, MTW in 54% and 35% were free from respiratory episodes. Pediatrician-based classification showed 59% EVW and 26% MTW. The Kappa measure of agreement between diary-based and pediatrician-assigned phenotypes was very low (0.12, 95%CI, 0.07-0.17). Phenotypic instability was observed in 32% of cases. PCR was positive in 71% during URTI symptoms, 66% during respiratory symptoms and 38% in the absence of symptoms.

CONCLUSION

This study shows that EVW and MTW are variable over time within patients. Pediatrician classification of these phenotypes based on clinical history does not correspond to prospectively recorded symptom patterns. The applicability of these phenotypes as a basis for therapeutic decisions and prognosis should be questioned.

Advances in the aetiology, management, and prevention of acute asthma attacks in children

Acute attacks of wheeze or asthma are among the most common reasons for paediatric hospital attendance, and the incidence of severe attacks in the UK is among the highest in Europe. Although most attacks are driven by infection, there are important differences in the underlying pathophysiology of asthma and wheeze between preschool and school-aged children. Allergen sensitisation, airway eosinophilia, and type 2 inflammation predominate in older children, whereas phenotypes in preschool children are variable, often including non-atopic episodes driven by neutrophilic infection. Currently, a universal approach is adopted towards management, but there is a need to make objective assessments of airway function, inflammation, and infection, both during the attack and during stable periods, to identify treatable traits and to target therapy if outcomes are to be improved. An assessment of the risk factors that led to the attack and early, focused follow-up are essential to ensure attacks never occur again.

Asthma in Children: A Brief Review for Primary Care Providers

Pediatric asthma is a common chronic condition with wide-ranging implications for children's health, their families, and the health care system. The diagnosis may be relatively straightforward for the child with characteristic symptoms, triggers, and response to therapy, but there are other less common presentations that can make the diagnosis challenging. Diagnosing asthma in a toddler with recurrent wheezing can be particularly difficult. Treating asthma in a step-wise fashion usually reduces symptom frequency and improves asthma control. Asthma exacerbations and poor outcomes from acute exacerbations remain an area in which we have room for improvement. This article provides an overview of the diagnosis and management of childhood asthma for the primary care provider. [Pediatr Ann. 2019;48(3):e103-e109.].

Analysis of the predicting factors of recurrent wheezing in infants

Background

Clinically, asthma in children under 5 years old is under estimated because lack of diagnostic criteria. The current study was, therefore, designed to identify the predicting factors for recurrent wheezing in infants.

Methods

One hundred forty-five infants under 3-year old hospitalized with respiratory diseases were enrolled into this study. Patients were followed up for one-year period after being discharged from the hospital and were, then, divided into recurrent wheezing group and non-recurrent wheezing group based on whether there was recurrent wheezing or not. Wheezing or recurrent wheezing was specifically monitored in addition to blood tests for allergic and respiratory diseases.

Results

The prevalence of eczema and respiratory syncytial virus (RSV) infection were significantly higher in recurrent wheezing group than in control group (74.2% vs 45.8%; 32.3% vs. 13.3%, respectively, both P < 0.05); the percentage of blood eosinophil and serum eosinophil-derived neurotoxin (EDN) concentration at admission were also higher in recurrent wheezing group than in control group (3.10 ± 2.54% vs. 1.31 ± 1.15%; 68.67 ± 55.05 ng/mL vs. 27. 36 ± 19.51 ng/mL; respectively, both P < 0.001). Multivariate logistic regression analysis on eosinophil count and serum EDN concentration in predicting recurrent wheezing revealed that the eosinophil count showed the lowest sensitivity (51.6%) and highest specificity (90.4%), with the area under the ROC curve (AUC) of 0.752 ± 0.041; and that, in contrast, the serum EDN showed the highest sensitivity (88.7%) and lowest specificity (56.6%), with AUC of 0.795 ± 0.037.

Conclusion

Combination of eosinophil count and serum EDN measurement may be better to predict the risk of recurrent wheezing in early life of childhood.

Approaches to Asthma Diagnosis in Children and Adults

Although the hallmark features of asthma include reversible airflow obstruction, airway eosinophilia, and symptoms of recurrent wheeze associated with breathlessness and cough, it is a heterogeneous disease. The extent of the pathophysiological abnormalities are variable between patients. Despite this, until recently, asthma diagnosis had been made very simplistically predominantly from a clinical history and examination, and often a trial of medication such as short acting bronchodilators. The limitations of this approach have become increasingly apparent with evidence of inappropriate over diagnosis, under diagnosis and misdiagnosis. Although there is no gold standard single test to make a diagnosis of asthma, there are several objective tests that can be used to support the diagnosis including physiological measures such as obstructive spirometry associated with bronchodilator reversibility and airway hyperresponsiveness. In addition, non-invasive tests of airway inflammation such as exhaled nitric oxide or peripheral blood eosinophils are important to identify those with an allergic or eosinophilic phenotype. Diagnostic guidelines reflect the importance of using objective tests to support a diagnosis of asthma, however practical application in the clinic may not be straightforward. The focus of this review is to discuss the need to undertake objective tests in all patients to support asthma diagnosis and not just rely on clinical features. The advantages, challenges and limitations of performing tests of lung function and airway inflammation in the clinic, the difficulties related to training and interpretation of results will be explored, and the utility and relevance of diagnostic tests will be compared in adults and children.

Management of Recurrent Preschool, Doctor-Diagnosed Wheeze

Preschool wheeze occurs in half of the children before they reach 6 y of age and recurrence is also common. Recurrent preschool wheeze is classified as either typical or atypical. For typical recurrent preschool wheeze, the diagnoses are either asthma or bronchiolitis/bronchitis. Responsiveness to a properly administered bronchodilator confirms asthma, atopic or otherwise. All atypical preschool wheeze should be referred to pediatric respirologist for assessment. Lung function test by impulse oscillometry (IOS) before and after bronchodilator is helpful to confirm airway hyperresponsiveness, an essential feature of asthma. Assessment of atopy is important by either skin prick test or serum IgE level. Treatment of acute wheeze includes standard supportive care, bronchodilator for those diagnosed with asthma and hypertonic saline for those diagnosed as having acute bronchiolitis. Other treatments included nebulized adrenaline for acute bronchiolitis and systemic steroids for asthma. For those with significant respiratory distress, continuous positive airway pressure (CPAP) or heated humidified high flow should be considered. Daily or intermittent inhaled corticosteroid or intermittent montelukast would reduce asthma exacerbation rate. A significant proportion of preschool wheeze persists till school age. An early diagnosis of asthma would be important to allow early optimal management.

Fifteen-minute consultation: An evidence-based approach to the child with preschool wheeze

Preschool wheeze is very common and its prevalence is increasing. It consumes considerable healthcare resources and has a major impact on children and their families due to significant morbidity associated with acute episodes.History taking is the main diagnostic instrument in the assessment of preschool wheeze. Diagnosis and management is complicated by a broad differential and associations with many other diseases and conditions that give rise to noisy breathing, which could be misinterpreted as wheeze. Several clinical phenotypes have been described but they have limitations and do not clearly inform therapeutic decisions. New insights in aetiopathogenesis modify treatment options and lay foundation for further research. An understanding of the approach and available evidence to assess and manage wheeze informs best patient care and use of resources.Our objective is to demonstrate a focused history, examination and management options in a preschool child with wheeze.

Prevalence and associated factors of wheezing illnesses of children aged three to five years living in under-served settlements of the Colombo Municipal Council in Sri Lanka: a cross-sectional study

BACKGROUND

A rising trend in Sri Lanka for asthma and wheezing illness is observed with higher morbidity in younger children and a paucity of related research. 'Under-served settlements' (USS) of Colombo Municipal Council (CMC) have poor living environments conducive to childhood wheezing. The objective was to describe the prevalence and associated factors of wheezing illnesses of three to five year old children living in low-income settlements in CMC.

METHODS

A cross-sectional study was conducted on 460 three to five year old children and their caregivers using cluster sampling among residents of two randomly selected USSs of CMC. An interviewer-administered questionnaire, observation checklist and data extraction form were used in data collection. A physician's diagnosis of wheezing/whistling of the chest in their lifetime and a physician's diagnosis of wheezing/whistling within the past twelve months were considered as 'ever-wheezing illness' and 'current-wheezing illness' respectively.

RESULTS

Mean age was 3.98 years (SD = ±0.64 years). A majority were males (51.3%) and Tamils (39.8%). Prevalence of 'ever wheezing illness' and 'current wheezing illness' were 38% (95% confidence interval (CI); 33.6%-42.5%) and 21.3% (95%CI; 17.6%-25.0%), respectively. Maternal (p < 0.001) and paternal (p < 0.001) histories of wheezing, playing with soft toys in the sleeping area (p = 0.004), place of cooking combined with the living area (p = 0.03), unsatisfactory ventilation in the sleeping area (p < 0.001) were found to be significantly associated with increased 'current wheezing' through multivariate analysis in this study. Use of formula milk before six months of age (p = 0.014) was found to be protective through multivariate analysis.

CONCLUSIONS

The magnitude of wheezing illnesses among three to five year old children residing in urban low-income settlements was found to be high. Children with a history of maternal and/or paternal wheezing should be targeted for early interventions to prevent wheezing illnesses. Interventions to avoid exacerbations should focus on the indoor environmental factors that were found to be associated with wheezing illnesses.

Infantile wheeze: rethinking dogma

Wheeze is a common symptom in young children and is usually associated with viral illnesses. It is a major source of morbidity and is responsible for a high consumption of healthcare and economic resources worldwide. A few children have a condition resembling classical asthma. Rarer specific conditions may have a wheezy component and should be considered in the differential diagnosis. Over the last half century, there have been many circular discussions about the best way of managing preschool wheeze. In general, intermittent wheezing should be treated with intermittent bronchodilator therapy, and a controller therapy should be prescribed for a young child with recurrent wheezing only if positively indicated, and only then if carefully monitored for efficacy. Good multidisciplinary support, attention to environmental exposition and education are essential in managing this common condition. This article analyses the pathophysiological basis of wheezing in infancy and critically discusses the evolution of the scientific progress over time in this unique field of respiratory medicine.

A young child with a history of wheeze

The parents of a 3-year old boy are anxious about their son who has recurring episodes of wheezing. They are frustrated that no one seems to be able to give them answers to their questions and would like a referral to a specialist. Does their son have asthma and what is the prognosis; how can the recurrent wheezing be managed and can the risk of asthma be reduced; are there lifestyle changes that could improve the environment and avoid triggers? Communication and support from the family practice team were essential. Listening to the parents' concerns, explaining the diagnostic uncertainty, being realistic about what drug treatments could achieve, and providing practical advice on inhaler use and trigger avoidance reassured the parents that there was a strategy for managing their son's wheeze. The specialist referral was postponed.

Should a Preschool Child with Acute Episodic Wheeze be Treated with Oral Corticosteroids? A Pro/Con Debate

Traditionally, preschool-aged children with an acute wheezing episode have been treated with oral corticosteroids (OCSs) based on the efficacy of OCSs in older children and adolescents. However, this practice has been recently challenged based on the results of recent studies. The argument supporting the use of OCSs underscores the observation that many children with recurrent preschool wheezing develop atopic disease in early life which predicts both an increased risk to develop asthma in later life and response to OCS therapy. Further, review of the literature demonstrates heterogeneity of study designs, OCS dosage, interventions, study medication adherence, and settings and overall lack of predefined preschool wheezing phenotypes. The heterogeneity of these studies does not allow a definitive recommendation discouraging OCS use. Advocates against the use of OCSs in this population argue that most of studies investigating the efficacy of OCSs in acute episodic wheeze in preschool-aged children have not demonstrated beneficial effects. Moreover, repeated OCS bursts may be associated with adverse effects. Finally, both sides can agree that there is a significant need to conduct efficacy trials evaluating OCS treatment in preschool-aged children with recurrent wheezing targeted at phenotypes that would be expected to respond to OCSs. This article presents a summary of recent literature regarding the use of OCSs for acute episodic wheezing in preschool-aged children and a "pro" and "con" debate for such use.

Effects of Triple P parenting intervention on child health outcomes for childhood asthma and eczema: Randomised controlled trial

Childhood chronic health conditions have considerable impact on children. We aimed to test the efficacy of a brief, group-based parenting intervention for improving illness-related child behaviour problems, parents' self-efficacy, quality of life, parents' competence with treatment, and symptom severity. A 2 (intervention vs. care as usual) by 3 (baseline, post-intervention, 6-month follow-up) design was used, with random group assignment. Participants were 107 parents of 2- to 10-year-old children with asthma and/or eczema. Parents completed self-report questionnaires, symptom diaries, and home observations were completed. The intervention comprised two 2-h group discussions based on Triple P. Parents in the intervention group reported (i) fewer eczema-related, but not asthma-related, child behaviour problems; (ii) improved self-efficacy for managing eczema, but not asthma; (iii) better quality of life for parent and family, but not child; (iv) no change in parental treatment competence; (v) reduced symptom severity, particularly for children prescribed corticosteroid-based treatments. Results demonstrate the potential for brief parenting interventions to improve childhood chronic illness management, child health outcomes, and family wellbeing. Effects were stronger for eczema-specific outcomes compared to asthma-specific outcomes. Effects on symptom severity are very promising, and further research examining effects on objective disease severity and treatment adherence is warranted.

AUSTRALIA NEW ZEALAND CLINICAL TRIALS REGISTRATION

ACTRN12611000558921.

Blood eosinophils as a marker of likely corticosteroid response in children with preschool wheeze: time for an eosinophil guided clinical trial?

Childhood wheezing is common particularly in children under the age of 6 years and in this age group is generally referred to as preschool wheezing. Particular diagnostic and treatment uncertainties exist in these young children due to the difficulty in obtaining objective evidence of reversible airways narrowing and inflammation. A diagnosis of asthma depends on the presence of relevant clinical signs and symptoms and the demonstration of reversible airways narrowing on lung function testing, which is difficult to perform in young children. Few treatments are available and inhaled corticosteroids are the recommended preventer treatment in most international asthma guidelines. There is, however, considerable controversy about its effectiveness in children with preschool wheeze and a corticosteroid responder phenotype has not been established. These diagnostic and treatment uncertainties in conjunction with the knowledge of corticosteroid side effects, in particular the reduction of growth velocity, have resulted in a variable approach to inhaled corticosteroid prescribing by medical practitioners and a reluctance in carers to regularly administer the treatment. Identifying children who are likely responders to corticosteroid therapy would be a major benefit in the management of this condition. Eosinophils have emerged as a promising biomarker of corticosteroid responsive airways disease, and evaluation of this biomarker in sputum has successfully been employed to direct management in adults with asthma. Obtaining sputum from young children is time consuming and difficult, and it is hard to justify more invasive procedures such as a bronchoscopy in young children routinely. Recently, in children, interest has shifted to assessing the value of less invasive biomarkers of likely corticosteroid response and the biomarker 'blood eosinophils' has emerged as an attractive candidate. The aim of this review was to summarize the evidence for blood eosinophils as a predictive biomarker for corticosteroid responsive disease with a particular focus on the difficult area of preschool wheeze.

Preschool Wheezing Phenotypes

Wheezing in preschool children is very common, with a wide differential diagnosis. It is essential to be sure of the exact sound that parents are describing; the term ‘wheeze‘ is often applied to non-specific sounds. Structural airway disease such as vascular ring should be considered. Thereafter we propose that umbrella terms for preschool wheeze should be abandoned in favour of ‘Hargreave phenotyping’, in which the presence and extent of the components of infection, inflammation, variable airflow obstruction, and fixed airflow obstruction are determined as far as is possible, rather than using a general umbrella term such as ‘asthma’. The justification for this approach is that it leads to a logical approach to treatment in the disparate airway diseases presenting in the preschool years, and should hopefully prevent over-treatment with inhaled corticosteroids. If, despite this approach, doubt remains as to the nature of the airway disease, then a therapeutic trial of treatment is permissible, but it should be for a short defined period only. In any event, such children should be reviewed regularly to see if treatments need to be changed.

Intermittent inhaled corticosteroid therapy versus placebo for persistent asthma in children and adults

BACKGROUND

International guidelines advocate using daily inhaled corticosteroids (ICS) in the management of children and adults with persistent asthma. However, in real world clinical settings, these medicines are often used at irregular intervals by patients. Recent evidence suggests that the use of intermittent ICS, with treatment initiated at the time of early symptoms, may still have benefits for reducing the severity of an asthma exacerbation.

OBJECTIVES

To compare the efficacy and safety of intermittent ICS versus placebo in the management of children and adults diagnosed with, or suspected to have, symptoms of mild persistent asthma.

SEARCH METHODS

We searched the Cochrane Airways Group Specialised Register of trials (CAGR), the ClinicalTrials.gov website and the World Health Organization (WHO) trials portal in March 2015.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that compared intermittent ICS versus placebo in children and adults with symptoms of persistent asthma. No co-interventions were permitted other than rescue relievers and oral corticosteroids used during exacerbations.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion, methodological quality and extracted data. The primary efficacy outcome was the risk of asthma exacerbations requiring oral corticosteroids and the primary safety outcome was serious adverse health events. Secondary outcomes included exacerbations, lung function tests, asthma control, adverse effects, and withdrawal rates. Quality of the evidence was assessed using the GRADE criteria.

MAIN RESULTS

Six trials (representing 490 preschool children, 145 school-aged children and 240 adults) met the inclusion criteria. Study durations were 12 to 52 weeks. Results for preschool children were presented in a separate analysis as this represents a distinct clinical condition, not necessarily related to the development of long term asthma.There was a reduction in the risk of patients experiencing one or more exacerbations requiring oral corticosteroids in older children (145 participants, odds ratio (OR) 0.57; 95% confidence interval (CI) 0.29 to 1.12, low quality evidence) and adults with asthma (240 participants, OR 0.10; 95% CI 0.01 to 1.95, low quality evidence). These analyses were each based on the findings of a single study. No group difference was observed in the risk of serious adverse health events (385 participants; OR 1.00; 95% CI 0.14 to 7.25, moderate quality evidence). Compared to the placebo group, there was an insufficient number of participants to make firm conclusions whether the intermittent ICS group displayed any reduction in the rate of hospitalisations, day time and night time symptoms scores, or adverse events. Lung function tests reported by a single study favoured the use of ICS. There was no significant group difference in growth rate of children, or overall withdrawals.In preschool children with frequent wheezing episodes, the use of intermittent ICS at the onset of early symptoms reduced the likelihood of requiring rescue oral corticosteroids by half (490 participants; OR: 0.48; 95% CI 0.31 to 0.73, moderate quality evidence with minimal heterogeneity). Intermittent therapy was associated with fewer serious adverse events (439 participants; OR 0.42; 95% CI 0.17 to 1.02, low quality evidence). There was no significant difference in hospitalisations or in a single study measuring parent perceived quality of life. However, intermittent therapy was associated with improvements in both day time and night time symptoms. There was no increase in the rates of withdrawals, and overall and treatment-specific adverse events.

AUTHORS' CONCLUSIONS

In children and adults with mild persistent asthma, two studies have shown that the use of intermittent ICS at the time of exacerbation reduced the chances of needing oral corticosteroids by half. This result is statistically significant if we assume that the effect size is the same for each study population (fixed effects model), but is not statistically significant when using a random effects model. However, the paucity of published evidence limits our conclusions towards the 'as-needed' use of this medication. The small number of studies and participants were the major reasons for downgrading the overall quality of the findings. A corresponding result was found in preschool children with wheeze. In this age group, an improvement in day time and night time asthma symptoms score and parental perceived quality of life of children similarly favoured the ICS group. However, there was no statistical difference in hospitalisation rates in any group. This treatment was not associated with any significant increase in adverse events. There was no growth suppression noted with the use of intermittent ICS in either preschool or school-aged children. Considering the limited number of available studies, we emphasise the need for more randomised controlled studies in order to confirm these findings.

Preschool wheeze is not asthma: a clinical dilemma

Recurrent wheezing is common in preschool children and often gets labelled as asthma. It is important to differentiate preschool wheeze from asthma through focused history, examination and exclusion of other serious conditions that may present as wheeze. Two different pragmatic clinical phenotypes viz. episodic viral wheeze (EVW) and multi-trigger wheeze (MTW) have been described although categories do not remain fixed and cross over is often seen in clinical practice. Episodic use of inhaled bronchodilators such as salbutamol when wheezy, is the mainstay of treatment along with non-pharmacological measures such as avoidance of environmental tobacco smoke and parental education. Inhaled corticosteroids are the first choice for maintenance therapy in MTW whereas montelukast may be useful when maintenance therapy is considered in EVW. Any maintenance therapy should be viewed as a trial and need to be discontinued in cases where no benefit has been demonstrated. Short term systemic steroid therapy should be reserved for excaerbation of wheezy symptoms where hospitalization is necessary. Prognosis is good in recurrent mild EVW although remission in atopic MTW is often not achieved and the children in the latter group go on to develop asthma.