Asthma in children : origins and outcomes

Asthma is one of the most common chronic diseases in the world. At school age, 4-7% of all children is experiencing asthmatic symptoms. Improvement of asthma control and health related quality of life (HRQOL) may lower the huge burden of this disease. This requires insight into the determinants of asthma control and asthma related quality of life. Although it seems to be attractive to control all the determinants of asthma control in order to achieve proper asthma management, in clinical practice we do not succeed. In this thesis, we showed that in children, upper and lower respiratory tract infections are important determinants of asthma control. We also found that during the fall asthmatic children experience lower HRQOL. This may be due to the higher prevalence of viruses during this season. We furthermore identified two self perceived triggers for wheeze that negatively influenced HRQOL: emotions and perceived foods and drinks that trigger wheeze. In 91% of the children that perceived food and drinks to trigger wheeze, food allergic symptoms were present. It is not unlikely that underlying fear for food related respiratory symptoms may be present in this group of children. Besides the important role viruses play in asthma control, some viruses are thought to be associated with the development of asthma. For instance, Respiratory Syncytial Virus (RSV), which is the most frequent cause for hospitalization in infancy. It is unknown why RSV causes mild disease in some children, and severe disease, requiring hospitalization, in others. In most hospitalized no risk factors are present. We showed that hospitalization for RSV bronchiolitis during infancy is associated with increased risk of wheezing, asthma, and impaired lung function at age 6, as compared to an unselected birth cohort. We also studied whether early treatment of RSV bronchiolitis affects these long term outcomes, and showed that high dose inhaled beclomethasone during RSV bronchiolitis does not affect lung function, nor prevents the development the atopic diseases during long term follow-up. An explanation for this ineffectiveness may be the fact that these children are predisposed to develop asthma and already have lower lung functions from birth. We studied this hypothesis and found that neonatal lung functions in children that would be hospitalized for a severe RSV infection in the first year of life were significantly lower than children experiencing a less severe RSV infection

Increased risk of wheeze and decreased lung function after respiratory syncytial virus infection

Contains fulltext : 138292.pdf (publisher's version ) (Open Access)BACKGROUND: A relationship between hospitalization for respiratory syncytial virus (RSV) bronchiolitis and asthma development has been suggested in case-control studies. OBJECTIVE: The aim of this study was to assess the risk of current wheeze, asthma, and lung function at school age in infants previously hospitalized for RSV bronchiolitis compared to non-hospitalized children. METHODS: For this study, data from a prospective birth cohort of unselected, term-born infants (n = 553), of whom 4 (0.7%) were hospitalized for RSV bronchiolitis, and a prospective patient cohort of 155 term infants hospitalized for RSV bronchiolitis were used. Respiratory outcomes at age 6 in children hospitalized for RSV bronchiolitis were compared to non-hospitalized children. RESULTS: The risk of current wheeze was higher in hospitalized patients (n = 159) compared to non-hospitalized children (n = 549) (adjusted odds ratio (OR) 3.2 (95% CI 1.2-8.1). Similarly, the risk of current asthma, defined as a doctor's diagnosis of asthma plus current symptoms or medication use, was higher in hospitalized patients (adjusted OR 3.1 (95% CI 1.3-7.5). Compared to non-hospitalized children, RSV bronchiolitis hospitalization was associated with lower lung function (mean difference FEV1% predicted -6.8 l (95% CI (-10.2 to -3.4). CONCLUSIONS AND CLINICAL RELEVANCE: This is the first study showing that hospitalization for RSV bronchiolitis during infancy is associated with increased risk of wheezing, current asthma, and impaired lung function as compared to an unselected birth cohort at age 6

Lack of long-term effects of high-dose inhaled beclomethasone for respiratory syncytial virus bronchiolitis: a randomized placebo-controlled trial

Item does not contain fulltextBACKGROUND: Previously, we showed that high-dose early initiated inhaled corticosteroids during respiratory syncytial virus bronchiolitis partially and transiently prevents subsequent recurrent wheeze. Here, we study treatment effect on lung function at age 6. METHODS: This is a 6-year follow-up report of a randomized placebo-controlled trial, in which 185 infants hospitalized for respiratory syncytial virus bronchiolitis were treated with early initiated, high-dose inhaled beclomethasone (n = 86) or placebo (n = 99) for 3 months. The primary outcome was forced expiratory volume in 1 second as percentage predicted. Secondary outcomes were bronchial hyperresponsiveness, physician-diagnosed asthma, hay fever and eczema. Possible toxicity was assessed by linear growth measurements. RESULTS: At age 6, no significant differences were found in mean forced expiratory volume in 1 second percentage predicted between beclomethasone-treated and placebo-treated patients (91.4 vs. 93.4, mean difference 2.05 (95% confidence interval: -1.98 to 6.08). The proportion of bronchial hyperresponsiveness, physician-diagnosed asthma, parent reported hay fever and eczema was comparable between groups. There were no differences in linear growth. CONCLUSIONS: Early initiated prolonged treatment with high-dose inhaled beclomethasone during hospitalization for respiratory syncytial virus infection during infancy did not improve the long-term respiratory outcome, but was safe

The expert network and electronic portal for children with respiratory and allergic symptoms: rationale and design

Abstract Data on baseline characteristics of children with asthma to predict individual treatment responses are lacking. We aimed to set up a data-collection system which can easily fill this gap in clinical practice. A web-based application was developed, named 'Portal for children with respiratory and allergic symptoms', hereafter called Electronic Portal (EP). It contains health- and disease-related questionnaires on respiratory- and allergic diseases. All patients, 1–18 years of age, with respiratory- and/or allergic complaints are invited to enter the EP before their first visit. By using the EP large amounts of data, gathered during routine patient care can be used for research purposes. This may help to further investigate the different treatment related asthma phenotypes and will be helpful to monitor risk factors for other atopic diseases and respiratory infections.</p

Increased Risk of Wheeze and Decreased Lung Function after Respiratory Syncytial Virus Infection

<div><p>Background</p><p>A relationship between hospitalization for respiratory syncytial virus (RSV) bronchiolitis and asthma development has been suggested in case-control studies.</p><p>Objective</p><p>The aim of this study was to assess the risk of current wheeze, asthma, and lung function at school age in infants previously hospitalized for RSV bronchiolitis compared to non-hospitalized children.</p><p>Methods</p><p>For this study, data from a prospective birth cohort of unselected, term-born infants (n = 553), of whom 4 (0.7%) were hospitalized for RSV bronchiolitis, and a prospective patient cohort of 155 term infants hospitalized for RSV bronchiolitis were used. Respiratory outcomes at age 6 in children hospitalized for RSV bronchiolitis were compared to non-hospitalized children.</p><p>Results</p><p>The risk of current wheeze was higher in hospitalized patients (n = 159) compared to non-hospitalized children (n = 549) (adjusted odds ratio (OR) 3.2 (95% CI 1.2–8.1). Similarly, the risk of current asthma, defined as a doctor’s diagnosis of asthma plus current symptoms or medication use, was higher in hospitalized patients (adjusted OR 3.1 (95% CI 1.3–7.5). Compared to non-hospitalized children, RSV bronchiolitis hospitalization was associated with lower lung function (mean difference FEV1% predicted −6.8 l (95% CI (−10.2 to −3.4).</p><p>Conclusions and Clinical Relevance</p><p>This is the first study showing that hospitalization for RSV bronchiolitis during infancy is associated with increased risk of wheezing, current asthma, and impaired lung function as compared to an unselected birth cohort at age 6.</p></div

Respiratory morbidity of hospitalized RSV bronchiolitis patients and non-hospitalized children at the age of 6 years.

<p>Data are numbers (percentages) unless stated otherwise;</p>*<p>Adjusted for sex and age;</p>**<p>Adjusted for sex, age, birth weight, birth season, smoke exposure during pregnancy and during life, breastfeeding, daycare, siblings, maternal atopy, ethnicity, year of birth, and maternal educational level;</p>***<p>Defined as combination of a history of doctor’s diagnosed asthma plus asthma symptoms or medication use in the last 12 months (beta-mimetics or inhaled corticosteroids).</p

Group characteristics at age 6 for 159 hospitalized RSV bronchiolitis patients [13], and non-hospitalized children [12].

<p>Data are numbers (percentages) unless stated otherwise.</p>*<p>Caucasian = Not born in Africa, Latin America and Asia (Japan and Indonesia excluded) or Turkey.</p

FEV₁ values presented as % predicted values for hospitalized RSV bronchiolitis patients and non-hospitalized children measured at the age of 6 years.

<p>Hospitalized patients had a lower mean FEV_1% predicted compared to non hospitalized children (93.3 (SD12.2) versus 100.3% (SD 13.9), mean difference −7.0 (95% CI (−9.7 to −4.2)).</p

Respiratory tract infections and asthma control in children

INTRODUCTION: Asthma control is considered the major goal of asthma management, while many determinants of control are difficult to modify. We studied the association between respiratory infection episodes (RTIs) of various types and asthma control. METHODS: Cross-sectional data were used from children aged 4-18 years with physician-diagnosed asthma who participated in a web-based electronic portal for children with asthma, allergies or infections. Asthma control was measured using the Childhood Asthma Control Test (C-ACT) or the Asthma Control Test (ACT). Linear regression was used to analyse the association between categories of numbers of various types of RTIs sustained in the preceding 12 months (categorized) and asthma control, adjusted for potential confounders. RESULTS: Asthma control was assessed in 654 children, and 68.5% were clinically well controlled (ACT ≥ 20). Higher total numbers of RTIs in the last 12 months were strongly associated with a lower level of asthma control (ptrend < 0.001). Similarly strong statistically significant associations were found for subtypes of RTI: ≥4 vs. 0 otitis episodes: coefficient -1.7 (95% CI -3.3 to -0.2); ≥5 vs.0 colds: coefficient -2.3 (95% CI -3.0 to -1.6); ≥3 vs. 0 bronchitis episodes: coefficient -3.1 (95% CI -4.0 to -2.3), each with ptrend < 0.05. CONCLUSION: Higher numbers of reported respiratory tract infections are associated with lower level of asthma control. The different type of respiratory tract infections contribute equally to less controlled asthma