Young children experience little emotional burden during invasive procedures in asthma research

Research in children should strike the right balance between protecting underage study subjects and advancing the medical field. This study gives insight into the emotional burden that common invasive research procedures in asthma research have on young children, both from the child and parent perspective. Puppetry was used to stimulate children (age 5-6 years) to explain their emotional burden prior to and after the research procedures. We operationalised emotional burden as willingness to participate in future research and reluctance towards participation. Parents filled out a questionnaire on this topic. Symptomatic patients as well as healthy controls were analysed. Forty-one children were included. Children's anticipatory fear for future research showed a clear decrease of 0.7 ± 1.6 on a 5-point Likert scale as a consequence of participation (p = 0.02). Sixty percent of all participating children explicitly indicated willingness to undergo identical research procedures again. Children uninformed by their parents about the venipuncture were significantly more reluctant to the venipuncture after the procedure (p < 0.01), compared to children who had been informed (4.0 ± 0.9 resp. 2.8 ± 1.2).Conclusion: This study suggests that the emotional burden of participation in asthma research for underage children can be prevented when they are properly informed and decreases as a consequence of participations. We believe increased emphasis should be placed on informing children and evaluating the emotional impact of research to help caretakers and research ethics committees make informed decisions about participation of children in medical research. What is Known: • Medical professionals and parents are likely to overestimate children's discomfort undergoing (invasive) research procedures. • Two thirds of children (age 6-18 years) participating in medical research indicated that they would participate in the same research study again. What is New: • Pre-school children experience little emotional burden during invasive procedures in asthma research. • Proper communication about (invasive) research procedures in pre-school children helps to reduce the anticipatory fear of these procedures in the future.

Exposure to Environmental Contaminants and Lung Function in Adolescents-Is There a Link?

Dioxins (polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDF)), polychlorinated biphenyls (PCBs), and brominated flame retardants (BDEs) are well known toxic environmental contaminants. Their possible role in the incidence of respiratory disease is not yet well understood. Previous studies showed a negative effect on lung function in relation to prenatal and lactational dioxin exposure in pre-pubertal children. Effects of BDE exposure on the lung function have not previously been evaluated. As part of a longitudinal cohort study, the effects of perinatal dioxin (PCDD/F) exposure and serum PCDD/F, dl-PCB, and BDE levels on lung function in adolescents were assessed using spirometry, a body box, and diffusion measurements. Thirty-three children (born between 1986 and 1991) consented to the current follow-up study. Prenatal, lactational, and current dioxin, PCB, and BDE concentrations were determined using GC-MS. No relationship was seen between prenatal and lactational dioxin exposure, nor with current PCB body burden, and lung function. Indications of increasing airway obstruction were seen in relation to increasing current BDE exposure. This is a novel finding and certainly warrants further research.

Exploring Immune Development in Infants With Moderate to Severe Atopic Dermatitis

Background

Atopic dermatitis (AD) is the most common chronic inflammatory skin disease in infancy with a complex pathology. In adults, the clinical severity of AD has been associated with increases in T helper cell type (Th) 2, Th22, and Th17 serum markers, including high levels of CC chemokine ligand (CCL) 17 and CCL22 chemokines.

Objective

To explore the possible association between serum chemokine levels and AD severity in infants with moderate-to-severe AD and elevated immunoglobulin E (IgE).

Subjects and methods

Serum samples (n = 41) obtained from a randomized, double-blind, and clinical dietary intervention study were used to study biomarkers in infants with AD. Baseline- and post-intervention samples (4 months) were used, six chemokines and nine ratios thereof were analyzed using Luminex and correlated to AD severity. In the initial study, the infants were randomized to receive extensively hydrolyzed whey-based formula without (control) or with short-chain galacto-oligosaccharides/long-chain fructo-oligosaccharides (9:1) and Bifidobacterium breve M-16V (active).

Results

31 Infants up to 11 months of age, with an objective-SCORAD score (oSCORAD) ≥ 20 and elevated total-IgE and/or specific-IgE levels were included. In time, the median oSCORAD decreased in both groups by −8 (control, p < 0.05; active, p < 0.01). Irrespective of dietary intervention, several changes in Th2 chemokines (CCL17 and CCL22), inflammatory chemokine (CCL20), and the Th1 chemokine, CXC chemokine ligand (CXCL) 9, were detected over time. Overall CCL17 correlated to oSCORAD (r = 0.446, p < 0.01). After 4 months of dietary intervention, CXCL9 was higher (p < 0.01) in the active group compared with control [active, 2.33 (1.99–2.89); controls, 1.95 (1.77–2.43) log 10 median (range)]. In addition, a reduction in Th2/Th1 chemokine ratios for CCL17/CXCL9, CCL22/CXCL9, CCL20/CXCL10, and CCL20/CXCL11 was detected associated with the active intervention.

Conclusion

While this study is small and exploratory in nature, these data contribute to immune biomarker profiling and understanding of AD in infants.

BMI predicts exercise induced bronchoconstriction in asthmatic boys

BACKGROUND

Exercise induced bronchoconstriction (EIB) is a frustrating morbidity of asthma in children. Obesity has been associated with asthma and with more severe EIB in asthmatic children.

OBJECTIVES

To quantify the effect of BMI on the risk of the occurrence of EIB in children with asthma.

METHODS

Data were collected from six studies in which exercise challenge tests were performed according to international guidelines. We included 212 Children aged 7-18 years, with a pediatrician-diagnosed mild-to-moderate asthma.

RESULTS

A total of 103 of 212 children (49%) had a positive exercise challenge (fall of FEV₁  ≥ 13%). The severity of EIB, as measured by the maximum fall in FEV₁ , was significantly greater in overweight and obese children compared to normal weight children (respectively 23.9% vs 17.9%; P = 0.045). Asthmatic children with a BMI z-score around +1 had a 2.9-fold higher risk of the prevalence of EIB compared to children with a BMI z-score around the mean (OR 2.9; 95%CI: 1.3-6.1; P < 0.01). An increase in BMI z-score of 0.1 in boys led to a 1.4-fold increased risk of EIB (OR 1.4; 95%CI: 1.0-1.9; P = 0.03). A reduction in pre-exercise FEV₁ was associated with a higher risk of EIB (last quartile six times higher risk compared to highest quartile (OR 6.1 [95%CI 2.5-14.5]).

CONCLUSIONS

The severity of EIB is significantly greater in children with overweight and obesity compared to non-overweight asthmatic children. Furthermore, this study shows that the BMI-z-score, even with a normal weight, is strongly associated with the incidence of EIB in asthmatic boys.

Remaining symptoms in half the children treated for milk allergy

The aim of this study was to investigate the cumulative incidence and predictive variables of treatment failure with a whey-based extensively hydrolyzed formula (w-eHF) in children with cow's milk allergy (CMA). All children were diagnosed with CMA, using double-blind placebo-controlled food challenge (DBPCFC) with amino acid-based formula as placebo, and receive w-eHF treatment after diagnosis. Forty-nine children with CMA were included. w-eHF treatment failure was defined as incomplete resolution of original CMA symptoms upon w-eHF treatment and disappearance of these symptoms upon replacement of w-eHF with amino acid-based formula. A multiple logistic regression model was used to investigate which variables could predict treatment failure. Twenty-five (51%; 95% confidence interval (CI) 38-64%) of the children with CMA failed on w-eHF. Only "gastrointestinal discomfort" was found to contribute independently to the probability of failing w-eHF, odds ratio (95% CI) 8.994 (1.007-79.457).

CONCLUSIONS

In half of the children with proven CMA, there is incomplete resolution of symptoms upon w-eHF treatment. This study needs to be repeated including DBPCFC with w-eHF to provide more definitive diagnosis, especially since gastrointestinal discomfort seems to be the sole predictive variable for treatment failure. In the meantime, a change in formula should be considered in children with incomplete symptom resolution upon w-eHF treatment.

Predicting asthma in preschool children at high risk presenting in primary care: development of a clinical asthma prediction score

BACKGROUND

A setting-specific asthma prediction score for preschool children with wheezing and/or dyspnoea presenting in primary healthcare is needed since existing indices are mainly based on general populations.

AIMS

To find an optimally informative yet practical set of predictors for the prediction of asthma in preschool children at high risk who present in primary healthcare.

METHODS

A total of 771 Dutch preschool children at high risk of asthma were followed prospectively until the age of six years. Data on asthma symptoms and environmental conditions were obtained using validated questionnaires and specific IgE was measured. At the age of six years the presence of asthma was assessed based on asthma symptoms, medication, and bronchial hyper-responsiveness. A clinical asthma prediction score (CAPS) was developed using bootstrapped multivariable regression methods.

RESULTS

In all, 438 children (56.8%) completed the study; the asthma prevalence at six years was 42.7%. Five parameters optimally predicted asthma: age, family history of asthma or allergy, wheezing-induced sleep disturbances, wheezing in the absence of common colds, and specific IgE. CAPS scores range from 0 to 11 points; scores <3 signified a negative predictive value of 78.4% while scores of >7 signified a positive predictive value of 74.3%.

CONCLUSIONS

We have developed an easy-to-use CAPS for preschool children with symptoms suggesting asthma who present in primary healthcare. After suitable validation, the CAPS may assist in guiding shared decision-making to tailor the need for medical or non-medical interventions. External validation of the CAPS is needed.

Altered exhaled biomarker profiles in children during and after rhinovirus-induced wheeze

Preschool rhinovirus-induced wheeze is associated with an increased risk of asthma. In adult asthma, exhaled volatile organic compounds (VOC) are associated with inflammatory activity. We therefore hypothesised that acute preschool wheeze is accompanied by a differential profile of exhaled VOC, which is maintained after resolution of symptoms in those children with rhinovirus-induced wheeze. We included 178 children (mean±sd age 22±9 months) from the EUROPA cohort comparing asymptomatic and wheezing children during respiratory symptoms and after recovery. Naso- and oropharyngeal swabs were tested for rhinovirus by quantitative PCR. Breath was collected via a spacer and analysed using an electronic nose. Between-group discrimination was assessed by constructing a 1000-fold cross-validated receiver operating characteristic curve. Analyses were stratified by rhinovirus presence/absence. Wheezing children demonstrated a different VOC profile when compared with asymptomatic children (p<0.001), regardless of the presence (area under the curve (AUC) 0.77, 95% CI 0.07) or absence (AUC 0.81, 95% CI 0.05) of rhinovirus. After symptomatic recovery, discriminative accuracy was maintained in children with rhinovirus-induced wheeze (AUC 0.84, 95% CI 0.06), whereas it dropped significantly in infants with non-rhinovirus-induced wheeze (AUC 0.67, 95% CI 0.06). Exhaled molecular profiles differ between preschool children with and without acute respiratory wheeze. This appears to be sustained in children with rhinovirus-induced wheeze after resolution of symptoms. Therefore, exhaled VOC may qualify as candidate biomarkers for early signs of asthma.

Inpatient treatment of children and adolescents with severe obesity in the Netherlands: a randomized clinical trial

IMPORTANCE

Severe childhood obesity has become a major health problem, and effective, evidence-based interventions are needed. The relative effectiveness of inpatient compared with ambulatory treatment remains unknown.

OBJECTIVE

To determine whether an inpatient treatment program is more effective than an ambulatory treatment program at achieving a sustained weight loss in children and adolescents with severe obesity.

DESIGN, SETTING, AND PARTICIPANTS

We conducted a randomized clinical trial with a 2-year follow-up at a tertiary referral center for pediatric obesity in the Netherlands. We recruited 90 children and adolescents aged 8 to 18 years with severe obesity (body mass index [BMI] z score, ≥3.0 or >2.3 with obesity-related health problems).

INTERVENTIONS

Patients were randomly assigned to an inpatient (6 months of hospitalization on working days) or an ambulatory (12 days of hospital visits at increasing intervals during a 6-month period) treatment program. Both treatment programs involved an intensive, family-based, lifestyle intervention, including exercise, nutritional education, and behavior modification for the patients and their caregiver(s).

MAIN OUTCOMES AND MEASURES

Change in BMI z score. Secondary outcomes included fasting insulin, fasting plasma glucose, 2-hour plasma glucose, and lipid levels, insulin sensitivity, liver function test results, waist circumference, blood pressure, body composition, and aerobic fitness (peak oxygen consumption, Vo₂). Outcomes were analyzed by intention to treat.

RESULTS

Immediately after treatment, reductions in the BMI z score were significantly larger for the inpatient than the ambulatory groups (mean [SE] difference, -0.26 [0.12; 95% CI, -0.59 to -0.01]; P = .04). Change from baseline for the BMI z score in the inpatient group was -18.0% (P = .001) immediately after treatment, -8.5% (P = .008) at 18 months, and -6.3% (P = .38) at 30 months; in the ambulatory group, changes from baseline were -10.5% (P = .001), -6.2% (P = .39), and -1.5% (P > .99), respectively. The favorable outcomes of the inpatient group could not be sustained at 12 and 24 months after treatment. In addition, significant differences in favor of the inpatient group immediately after treatment were found for levels of fasting insulin (-6.37 IU/L; P = .02), total cholesterol (-19.51 mg/dL; P = .01), low-density lipoprotein cholesterol (-13.48 mg/dL; P = .03), and triglycerides (-25.39 mg/dL; P = .01), and insulin sensitivity (-1.37; P = .02), fat mass (-3.31%; P = .03), and peak Vo₂ (378.2 mL/min; P = .01).

CONCLUSIONS AND RELEVANCE

In severely obese children and adolescents, inpatient treatment was superior to ambulatory treatment immediately after treatment, but effects were not sustained at long-term follow-up. These findings stress the need to further study maintenance strategies for sustainable weight loss.

TRIAL REGISTRATION

trialregister.nl Identifier: NTR1172.

Problematic severe asthma in children treated at high altitude: tapering the dose while improving control

BACKGROUND

Multidisciplinary treatment at high altitude is a possible treatment option for problematic severe asthma (PSA) in children. This management can result in the tapering of inhaled corticosteroids.

AIM

Our aim was to analyze the effect of multidisciplinary treatment at high altitude, notably the ability to taper corticosteroids. To get an insight into possible factors influencing tapering, we examined whether demographic variables, disease control and quality of life at treatment entrance could predict the tapering of corticosteroids.

METHODS

This prospective open-phase cohort study analyzed the data of 43 children aged 8-17 years referred to a specialized high altitude treatment centre. Lung function (FEV1, FEV1/VC), inflammation (FeNO), medication level, asthma control (ACT) and quality of life [PAQLQ(S)] were evaluated on admission and at discharge.

RESULTS

Thirty-two (74%) children fulfilled PSA criteria. Three (7%) children used daily oral steroids. After 72 ± 30 (mean ± SD) days of treatment, the mean dosage of inhaled corticosteroids (ICS) could be significantly reduced from 1315 μg ± 666 budesonide equivalent to 1132 μg ± 514. Oral steroid maintenance therapy could be stopped in all patients. FeNO, asthma control and quality of life improved (p < 0.001) from admission to discharge; FEV1 was in the normal range on both occasions. Apart from ICS levels at entrance, multiple regression analyses did not show any associated factor predicting the reduction of ICS dosage during treatment.

CONCLUSION

The results indicate that high altitude treatment may be a treatment option for children with PSA, but it is not possible to predict ICS tapering off from health status variables at treatment entrance.

A systematic review with attempted network meta-analysis of asthma therapy recommended for five to eighteen year olds in GINA steps three and four

Background

The recommendations for the treatment of moderate persistent asthma in the Global Initiative for Asthma (GINA) guidelines for paediatric asthma are mainly based on scientific evidence extrapolated from studies in adults or on consensus. Furthermore, clinical decision-making would benefit from formal ranking of treatments in terms of effectiveness.

Our objective is to assess all randomized trial-based evidence specifically pertaining to 5-18 year olds with moderate persistent asthma. Rank the different drug treatments of GINA guideline steps 3&4 in terms of effectiveness.

Methods

Systematic review with network meta-analysis. After a comprehensive search in Central, Medline, Embase, CINAHL and the WHO search portal two reviewers selected RCTs performed in 4,129 children from 5-18 year old, with moderate persistent asthma comparing any GINA step 3&4 medication options. Further quality was assessed according the Cochrane Collaboration’s tool and data-extracted included papers and built a network of the trials. Attempt at ranking treatments with formal statistical methods employing direct and indirect (e.g. through placebo) connections between all treatments.

Results

8,175 references were screened; 23 randomized trials (RCT), comparing head-to-head (n=17) or against placebo (n=10), met the inclusion criteria. Except for theophylline as add-on therapy in step 4, a closed network allowed all comparisons to be made, either directly or indirectly. Huge variation in, and incomplete reporting of, outcome measurements across RCTs precluded assessment of relative efficacies.

Conclusion

Evidence-based ranking of effectiveness of drug treatments in GINA steps 3&4 is not possible yet. Existing initiatives for harmonization of outcome measurements in asthma trials need urgent implementation.

Monitoring pulmonary function during exercise in children with asthma

OBJECTIVE

Exercise-induced bronchoconstriction (EIB) is defined as acute, reversible bronchoconstriction induced by physical exercise. It is widely believed that EIB occurs after exercise. However, in children with asthma the time to maximal bronchoconstriction after exercise is short, suggesting that the onset of EIB in such children occurs during exercise.

AIM

In this study the authors investigate pulmonary function during exercise in cold air in children with asthma.

METHODS

33 Children with asthma with a mean age of 12.3 years and a clinical history of exercise induced symptoms, underwent a prolonged, submaximal, exercise test of 12 min duration at approximately 80% of the predicted maximum heart rate. Pulmonary function was measured before and each minute during exercise. If EIB occurred (fall in forced expiratory volume in 1 s >15% from baseline), exercise was terminated and salbutamol was administered.

RESULTS

19 Children showed EIB. In 12 of these children bronchoconstriction occurred during exercise (breakthrough EIB), while seven children showed bronchoconstriction immediately after exercise (non-breakthrough EIB). Breakthrough EIB occurred between 6 and 10 min of exercise (mean 7.75 min).

CONCLUSION

In the majority of children with EIB in this study (ie, 12 out of 19), bronchoconstriction started during, and not after, a submaximal exercise test.

Inhaled corticosteroids in childhood asthma: the story continues

Inhaled corticosteroids (ICS) are the most effective anti-inflammatory drugs for the treatment of persistent asthma in children. Treatment with ICS decreases asthma mortality and morbidity, reduces symptoms, improves lung function, reduces bronchial hyperresponsiveness and reduces the number of exacerbations. The efficacy of ICS in preschool wheezing is controversial. A recent task force from the European Respiratory Society on preschool wheeze defined two different phenotypes: episodic viral wheeze, wheeze that occurs only during respiratory viral infections, and multiple-trigger wheeze, where wheeze also occurs in between viral episodes. Treatment with ICS appears to be more efficacious in the latter phenotype. Small particle ICS may offer a potential benefit in preschool children because of the favourable spray characteristics. However, the efficacy of small particle ICS in preschool children has not yet been evaluated in prospective clinical trials. The use of ICS in school children with asthma is safe with regard to systemic side effects on the hypothalamic-pituitary-adrenal axis, growth and bone metabolism, when used in low to medium doses. Although safety data in wheezing preschoolers is limited, the data are reassuring. Also for this age group, adverse events tend to be minimal when the ICS is used in appropriate doses.

Constipation and colonic transit times in children with morbid obesity

OBJECTIVES

The aim of the study was to determine the frequency of functional constipation according to the Rome III criteria in children with morbid obesity and to evaluate by measuring colonic transit times (CTTs) whether decreased colonic motility is present in these children.

PATIENTS AND METHODS

Ninety-one children with morbid obesity ages 8 to 18 years, entering a prospective, randomized controlled study evaluating the effect of an outpatient versus inpatient treatment program of obesity, participated. All of the children filled out a standardized questionnaire regarding their bowel habits, and CTTs were measured using radioopaque markers. Food diaries were also recorded to evaluate their diet.

RESULTS

A total of 19 children (21%) had functional constipation according to the Rome III criteria, whereas 1 child had functional nonretentive fecal incontinence. Total CTT exceeded 62 hours in only 10.5% of the children with constipation, and among them, 2 had a total CTT of >100 hours. In the nonconstipated group 8.3% had a delayed CTT. Furthermore, no difference was found between the diet of children with or without constipation, specifically not with respect to fiber and fat intake.

CONCLUSIONS

Our study confirms a high frequency of functional constipation in children with obesity, using the Rome III criteria. However, abnormal colonic motility, as measured by CTT, was delayed in only a minority of patients. No relation was found between constipation in these children and fiber or fat intake.

[Pneumomediastinum in a child]

BACKGROUND

Pneumomediastinum is a rare, benign condition in which air leaks through the alveolar membrane and collects in the mediastinum. Typical clinical symptoms include chest pain and dyspnoea. In the absence of underlying pathology, conservative treatment is sufficient for remission. Complications are infrequent.

CASE DESCRIPTION

We present a case of a 14-year-old boy with pneumomediastinum arising during physical exercise after an earlier episode of coughing. Physical examination showed subcutaneous emphysema in the neck and praecordial systolic crepitations. A chest X-ray revealed air in the mediastinum. Conservative treatment was sufficient for full clinical and radiographic recovery.

CONCLUSION

There was no underlying pathology. The diagnosis was therefore a 'spontaneous pneumomediastinum' possibly caused by a Valsalva manoeuvre after physical exercise and chronic coughing.

Probiotics and prebiotics in atopic dermatitis: review of the theoretical background and clinical evidence

The prevalence of atopic dermatitis (AD) has risen over the past decades, especially in western societies. According to the revised hygiene hypothesis this increase is caused by a changed intestinal colonization pattern during infancy, which has an impact on the immune system. Manipulating the intestinal microflora with pro-, pre- or synbiotics is an innovative way to prevent or treat AD. This review provides an overview of the theoretical basis for using probiotics and prebiotics in AD and presents the current evidence from randomized controlled trials (RCTs) regarding prevention and treatment of AD and food allergy in children with pro-, pre- and synbiotics. Seven RCTs on prevention and 12 RCTs on treatment were found by searching the Pubmed, Embase and Cochrane databases. Results of these trials are conflicting. In conclusion, at this moment there is not enough evidence to support the use of pro-, pre- or synbiotics for prevention or treatment of AD in children in clinical practice.

Effects of dioxins, PCBs, and PBDEs on immunology and hematology in adolescents

Dioxins and PCBs are environmental pollutants, proven to be immunotoxic. In the period 1987-1991 a cohort of mother-baby pairs was initiated to detect abnormalities in relation to dioxin levels in the mother's milk. At birth and at follow-up at 8-12 years, immunological and hematological effects were seen, prompting us to perform a new follow-up during adolescence. In addition, we assessed the immunological and hematological parameters in relation to current levels of PBDEs and PCBs. In the Netherlands, the pre- and postnatal exposure to dioxins have been studied prospectively since 1987. Venapuncture was performed to assess hematological (Hemoglobin, thrombocytes, thrombopoietin) and immunological (leukocytes, leukocyte differentiation) parameters and the current serum levels of dioxin, dioxinlike (dl)-PCBs and PBDEs. A decrease in the number of polymorphic neutrophils was found in adolescents with higher dl-PCBs in their serum (p = 0.021). No relation with total leukocytes, thrombocytes, hemoglobin, or thrombopoietin levels was seen. Similarly, we found no relation between prenatal, nor current dioxin levels and the hematological and the immunological parameters determined. The SigmaPBDEs were negatively associated with the number of lymphocytes (p = 0.01) and positively associated with the hemoglobin concentration (p = 0.003). These effects on the innate immunity by current levels of dl-PCBs and on the adaptive immunity by PBDEs are disconcerting, especially as the dl-PCB (0.04-7.8 WHOTEQ pg/g lipid, mean: 2.2 WHOTEQ pg/g lipid) and SigmaPBDE levels (mean 14.0 ng/g lipid, including one outlier with a sum of 73.6 ng/g lipid) were not high.

Delayed initiation of breast development in girls with higher prenatal dioxin exposure; a longitudinal cohort study

OBJECTIVES

While many studies have assessed the health impacts of PCDD/Fs and PCBs on animals and humans, long-term consequences for especially adolescents, have not (yet) been well documented. This is certainly also true for the effects of PBDE exposure. As part of a longitudinal cohort study, now well into its second decade, effects of perinatal and current PCDD/F exposure, as well as current dl-PCB and PBDE exposures, on puberty, were assessed.

STUDY DESIGN

Prenatal, lactational and current PCDD/F, dl-PCB and PBDE concentrations were determined using GC-MS. Pubertal development and growth were assessed by means of physical examination and the Tanner scale. 33 Children (born between 1986 and 1991) consented to the current follow-up study. Outcomes were evaluated using linear regression or the non parametric Spearman's correlation coefficient.

RESULTS

A delay in initiation of breast development was found in girls (n = 18) with higher prenatal (p = 0.023) and lactational PCDD/F exposure (p = 0.048). The males revealed a negative trend with age at first ejaculation. For other endpoints on puberty and growth (pubic hair, axillary hair, genital stage, length, BMI, testicular volume, menarche) no significant relation was found with any of the measured compounds.

DISCUSSION AND CONCLUSION

A relation between prenatal PCDD/F exposure and later initiation of breast development was seen. A Belgian study found a delay in breast development with higher current serum concentrations of dioxin-like compounds. The initiation of puberty is a complex process and it is yet not clear how dioxin-like compounds precisely affect this process prenatally. Further follow-up into adulthood is warranted, in order to detect the possibility of developing malignancies and fertility problems.

Implementation of an asthma guideline for the management of childhood asthma in general practice: a randomised controlled trial

AIM

The aim of the study was to assess, in a randomised, controlled design, the efficacy of different strategies to improve childhood asthma management.

METHOD

Three interventions directed to three groups of general practitioners were compared: Group A - dissemination of a guideline; Group B - guideline dissemination plus an educational session; Group C - guideline dissemination, educational session, plus individualised treatment advice based on airway hyperresponsiveness (AHR) and symptoms. Efficacy of the three strategies was assessed by evaluating change in AHR in 362 children after one year.

RESULTS

The overall between-group effect of the severity of AHR was not significantly different (P=0.09). In Groups A and C an improvement was seen in nocturnal symptoms (P=0.02) and in Group C an improvement was seen in the prescription of inhaled corticosteroids (P=0.03).

CONCLUSION

In this study, the combined implementation strategy did not show a clear improvement in the management of children with asthma in general practice.

Limitations of questioning asthma to assess asthma control in general practice

BACKGROUND

The monitoring of children with asthma in primary care is based on the occurrence and frequency of asthma symptoms. We questioned whether the current approach is adequate to identify all children in whom a sufficient level of asthma control is not achieved.

AIM

The aim of this study is to illustrate that in some children asthma was incorrectly considered controlled, because the children failed to report current symptoms of asthma.

PATIENTS AND METHODS

One hundred and nineteen children were identified with recent wheezing plus moderate or severe airway hyperresponsiveness. We analyzed whether these children reported current symptoms of asthma (as normally questioned during a routine visit).

RESULTS

In 20 children (18%) current asthma symptoms were absent despite moderately or severe airway hyperresponsiveness and wheezing in the last year. In addition, the usage of controller medication was very poor.

CONCLUSION

We conclude that the general practitioner has insufficient tools to adequately assess asthma control in all children. The assessment of airway hyperresponsiveness as an additional guide to manage asthma in children in general practice is recommended. In this way, better asthma control can be achieved.

Assessment of inhalation technique in children in general practice: increased risk of incorrect performance with new device

In a general practice based population 76% of 530 children inhaling asthma medication inhaled correctly. However, important differences among inhalers were found. Children with a pressurized metered-dose inhaler without a spacer device performed worst, with only 22% inhaling without essential errors. At a second evaluation of the inhaler technique, one year after the first assessment, performances with a new device were more often incorrect versus the unchanged devices (21.1% and 10.8%, respectively; p = 0.01). Providing children with a new device should be carefully controlled over time especially because these children are error prone.

Lung function after the minimal invasive pectus excavatum repair (Nuss procedure)

Background

The Nuss procedure was introduced at our center in 1999. The operation was mainly performed for cosmesis. Little information is available regarding the influence of this operation on lung function.

Methods

The aim of this study, a prospective analysis, was to analyze the effect of the Nuss procedure on lung function variables. Between 1999 and 2007 a total of 203 patients with pectus excavatum were treated with the Nuss procedure, of whom 145 (104 male, 41 female) were located at Emma Children’s Hospital. In the latter subset of consecutive patients, static lung function variables [total lung capacity (TLC), functional residual capacity (FRC), vital capacity (VC)] and dynamic lung function variables [forced expired volume in 1 s (FEV₁), maximum expiratory flow (MEF₅₀)] were performed using spirometry and body box measurements at four time points: prior to operation (T0), 6 months after the Nuss procedure (T1, n = 111), prior to removal of the Nuss bar (T2, n = 74), and 6 months after removal (T3, n = 53). All values were expressed as a percent of normal values for sex, age, and height. Results were compared with a paired-samples t-test, with the level of significance at p = 0.05.

Results

At 6 months after bar insertion the TLC, FRC, VC, FEV₁, and MEF₅₀ showed a significant increase; and prior to bar removal the FRC and MEF₅₀ showed significantly increased values. At 6 months after Nuss bar removal, none of the lung function variables showed any significant change compared to the preoperative values.

Conclusion

After the Nuss procedure for pectus excavatum, there was no improvement of pulmonary function, but neither was the patient’s pulmonary function harmed by resolving a largely cosmetic problem.

Electromyographic monitoring of respiratory muscle activity in dyspneic infants and toddlers

The aim of this study was to investigate whether the changes that occurred in the clinical asthma score (CAS) correlated with the changes in the respiratory electromyographic (EMG) activity over the days during admission to hospital in dyspneic infants and toddlers. Sixteen infants and toddlers (9 males) were studied during admission and 7 days after discharge. The CAS was used to assess the severity of dyspnea and consists of five items: respiration rate, wheezing, retractions, observed dyspnea, and inspiration-to-expiration ratio. Each item was scaled 0, 1, or 2, with a maximum score of 10. Electrical activity from the diaphragm (di) and intercostal muscles (int) was derived from surface electrodes. The logarithm of the EMG-Activity-Ratio (log EMGAR; ratio of mean peak-to-bottom EMG activity during admission to the hospital, to that at baseline, 7 days after discharge) was used as EMG parameter. For assessing the association between the repeated observations of the CAS and the EMG measurements we used the quantity r2 obtained with analysis of covariance. On the day of admission the patients had a mean CAS of 5.9 +/- 1.2. On the day of discharge the mean CAS decreased significantly to 2.1 +/- 1.6, indicating that the CAS returned to normal values. In line with this observation, a significant decrease in the log EMGARdi and log EMGARint was observed during the stay in the hospital. Over all subjects the correlation coefficient (r) of log EMGARdi versus CAS was 0.71, log EMGARint versus CAS was 0.67, and the mean log EMGAR versus CAS was 0.75 (p < 0.01, for all values). The correlation coefficients of subjects of < or = 1 year seemed to be lower than those of subjects of > 1 year of age (p < 0.01) and female subjects showed higher correlation coefficients than males. This study showed a moderate, but significant, relationship between the changes that occurred in the CAS and the changes in respiratory EMG activity during admission to hospital in dyspneic infants and toddlers. Moreover, the correlation coefficients of the combined leads of the intercostals and diaphragm (mean log EMGAR) were higher than those of the separate leads. The EMG measurements would extend diagnostic possibilities and would provide an objective measure to evaluate the clinical course of the disease and the efficacy of therapy in infants and toddlers with recurrent wheezing disorders.

The influence of intravenous hydrocortisone on cytokine levels in children with asthma

Nocturnal airway obstruction occurs frequently in childhood asthma and results from increased airway inflammation. Lymphocytes are believed to be key effector cells of airway wall inflammation, releasing pro-inflammatory mediators and cytokines. A previous study showed that hydrocortisone infusion, an effective anti-inflammatory treatment, improves nocturnal and daytime FEV(1) values. This study in 16 children with moderate asthma was designed to assess whether there exists day and night differences in IL-4, IL-5, IL-8, and IFN-gamma production of concanavaline A stimulated peripheral blood mononuclear cells. Furthermore, we investigated whether substitution of low serum cortisol levels with intravenous hydrocortisone would affect those parameters. Saline (as a placebo) or hydrocortisone (30 microg/m(2) body surface area/24 h) was intravenously administered in a randomized, double blind, cross-over design. Measurements under saline or hydrocortisone infusions were separated by 1 wk. At 04:00 and 16:00 hours 10 ml blood was taken for determination of peripheral blood mononuclear cell isolation and stimulation, and an eosinophil count. Hydrocortisone infusion significantly reduced the nocturnal fall in FEV(1). Median values of IFNgamma, IL-4, IL-5, and IL-8 produced by peripheral blood mononuclear cells did not significantly differ at 04:00 and 16:00 hours, both with saline and hydrocortisone infusion. Our results suggest that FEV(1) improvement is not due to suppression of circulating peripheral blood mononuclear cell activation. We hypothesize that it is rather due to its effect on local lung tissue epithelial and/or fibroblasts thereby reducing airway inflammation and vascular leakage.

Accuracy of specific IgE in the prediction of asthma: development of a scoring formula for general practice

BACKGROUND

For the diagnosis of asthma in young children, GPs have to rely on history taking and physical examination, as spirometry is not possible. The additional diagnostic value of specific immunoglobulin E (IgE) to inhalent allergens remains unclear.

AIM

To assess the predictive accuracy of specific IgE to cat, dog, and/or house dust mites in young children for the subsequent development of asthma at the age of 6 years.

DESIGN OF STUDY

Prospective follow-up study.

SETTING

Seventy-two general practices.

METHOD

A total of 654 children, aged 1-4 years, visiting their GPs for persistent coughing (>/= 5 days), were tested for IgE antibodies by radio allergosorbent testing (RAST). Parents completed a questionnaire on potential risk indicators. Those children who showed an IgE-positive status (12.7%) and a random sample of those with an IgE-negative status (<0.5 U/ml) were followed up to the age of 6 years when the asthma status was established. The main outcome measure was asthma at the age of 6 years (combination of both symptoms and/or use of asthma medication, and impaired lung function).

RESULTS

Addition of RAST results to a prediction model based on age, wheeze, and family history of pollen allergy increased the area under the receiver operating characteristic (ROC) curve from 0.76 to 0.87. Furthermore, RAST improved patient differentiation as indicated by a change in the range of asthma probabilities from 6-75% before the IgE test, to 1-95% after the IgE-test.

CONCLUSION

Sensitisation to inhalant allergens in 1-4-year-olds, as shown by RAST, is a useful diagnostic indicator for the presence of asthma at the age of 6 years, even after a clinical history has been obtained. This model should preferably be validated in a new population before it can be applied in practice.

Perinatal risk factors for bronchial hyperresponsiveness and atopy after a follow-up of 20 years

BACKGROUND

Perinatal risk factors are associated with lung function and respiratory symptoms in adult life. Whether the same holds for distinctive asthma features, such as bronchial hyperresponsiveness (BHR) and atopy, has scarcely been studied.

OBJECTIVE

We sought to identify the perinatal risk factors for the development of BHR and atopy.

METHODS

BHR and atopy were measured after 20 years' follow-up in 597 of 3162 babies born from 1975 through 1978. Factors directly related to delivery of these children were studied in association with the presence of BHR and atopy.

RESULTS

Twenty-five percent had BHR, and 47% had atopy. Delivery duration of longer than 12 hours was associated with the development of atopy (odds ratio [OR], 2.24; 95% CI, 1.30-3.86), and severe respiratory infection in the first year of life was associated with the development of BHR (OR, 2.69; 95% CI, 1.41-5.16). Nonatopic subjects born after induced labor and current smokers were more likely to have BHR (ORs of 2.41 [95% CI, 1.07-5.41] and 2.50 [95% CI, 1.12-5.59], respectively). Prenatal smoke exposure and childhood pet keeping decreased the risk for atopy, especially in BHR-positive subjects (ORs of 0.51 [95% CI, 0.27-0.99] and 0.46 [95% CI, 0.24-0.88], respectively).

CONCLUSIONS

It has been shown that events before or during birth still have an effect on respiratory health 20 years later. We put forward that an extreme hormonal status during delivery primes the fetal immune system toward atopy development. Furthermore, a severe respiratory infection in the first year of life appears associated with BHR development, and prenatal smoke exposure might be protective for the development of atopy, yet explanatory mechanisms are lacking thus far.

Randomized controlled trial of aerosolized prostacyclin therapy in children with acute lung injury

OBJECTIVES

To investigate whether aerosolized prostacyclin improves oxygenation in children with acute lung injury.

DESIGN

Double-blind, randomized, and placebo-controlled trial.

SETTING

Pediatric intensive care unit at a university hospital.

PATIENTS

Fourteen children with acute lung injury defined by the criteria of an American-European Consensus Conference.

INTERVENTIONS

Aerosolized prostacyclin (epoprostenol sodium) by stepwise increments of different doses (10, 20, 30, 40, and 50 ng x kg x min) vs. aerosolized normal saline (placebo).

MEASUREMENTS AND MAIN RESULTS

Before the start of the study, and before and after each dose of prostacyclin/placebo, the following variables were measured: arterial blood gases, heart rate, mean arterial blood pressure, and ventilator settings required. Changes in oxygenation were measured by calculation of the oxygenation index (mean airway pressure x 100 x Pao2/Fio2). After treatment with aerosolized prostacyclin, there was a significant 26% (interquartile range, 3%, 35%) improvement in oxygenation index at 30 ng x kg x min compared with placebo (p =.001). The response to prostacyclin was not the same in all children. We saw an improvement of > or = 20% in eight of 14 children (i.e., responders), and the number needed to treat was 1.8 (95% confidence interval, 1.2-3.2). No adverse effects were observed.

CONCLUSIONS

Aerosolized prostacyclin improves oxygenation in children with acute lung injury. Future trials should investigate whether this treatment will positively affect outcome.

Impact of wheezing after respiratory syncytial virus infection on health-related quality of life

BACKGROUND

Respiratory syncytial virus (RSV) lower respiratory tract infection (LRTI) is often followed by recurrent wheezing episodes during childhood. The effect of postbronchiolitis wheezing on the well-being of the child is not known. This study aimed to determine the impact of RSV LRTI hospitalization before age 13 months on health-related quality of life (HRQoL) at age 3 years.

METHODS

HRQoL was measured in a previously described cohort of children with a history of RSV infection and compared with control term children from the open population. HRQoL was determined during the winter season in index and control children. We used a validated questionnaire, which measures the health status of children in 13 domains weighted by the impact of the health status problems on well-being. The lung domain was the focus of this study. In addition daily respiratory symptoms of the index children were recorded prospectively up to age 3 years and correlated with HRQoL scores.

RESULTS

HRQoL was lower in index children (n = 128) than in control children (n = 340) for the lung, gastrointestinal tract and sleeping domains. HRQoL scores for social and developmental domains were similar for index and control children. As anticipated the largest difference between index and control children was found in the lung domain (77.6 +/- 2.2 vs. 93.9 +/- 0.8, P < 0.01). HRQoL in the lung domain was lower during the winter than during the summer season (77.6 +/- 2.2 vs. 85.6 +/- 1.9, P < 0.01), which was explained by increased airway morbidity during the winter season. We found a high correlation between lung HRQoL scores and total number of wheezing days during follow-up.

CONCLUSIONS

Postbronchiolitis wheezing has broad implications for long-term well-being of children. Decreased HRQoL was attributed to postbronchiolitis wheezing, but not to preexistent risk factors, such as premature birth. This study underscores the importance of developing new strategies to prevent and treat long term airway morbidity after RSV LRTI.

Histamine induced airway response in pre-school children assessed by a non-invasive EMG technique

The aim of the study was to investigate the association between surface electromyographic (EMG) activity of the diaphragm and intercostal muscles, and clinical symptoms (wheeze, cough, increased respiratory rate and prolonged expiration) during bronchial challenge testing and after administration of salbutamol in asthmatic pre-school children. A histamine challenge test was performed in 20 asthmatic pre-school children. The histamine dose at the appearance of 1 or more clinical symptoms was defined as the maximum histamine provocation dose (PDcs). The clinical symptoms were recorded with a microphone over the trachea. The logarithm of the EMG-Activity-Ratio (log EMGAR; mean peak activity ratio to baseline of respiratory muscles during tidal breathing) was used as EMG parameter. In both the diaphragmatic and the intercostal log EMGAR values a linear increase was observed in the four histamine dose-steps prior to PDcs. At PDcs the mean log EMGAR of the diaphragm (di) and intercostal muscles (int) was significantly increased as compared to the baseline values. After administration of salbutamol the log EMGARdi and log EMGARint returned to baseline values and the clinical symptoms normalized in all children. At PDcs, no significant differences in the log EMGAR values could be detected at the appearance of the distinctive clinical symptoms, which suggests that wheezing is not the only indicator for the detection of airway responsiveness in young children. We found a linear association between histamine dose and the increase in surface diaphragmatic and intercostal respiratory EMG activity during a bronchial challenge test in pre-school asthmatic children, which returned to baseline values after inhalation of salbutamol. These findings support the idea that EMG measurements of the diaphragm and intercostal muscles may offer an opportunity to estimate airway response in young children in an alternative way.

Airflow limitation in asthmatic children assessed with a non-invasive EMG technique

The aim of the study was to investigate the association between electromyography (EMG) of the diaphragm and intercostal muscles and the forced expiratory volume in 1 s (FEV(1)) at different levels of histamine-induced airflow limitation, and the response to salbutamol. Moreover, we assessed the reproducibility of the EMG measurements on 2 different occasions during different levels of airflow limitation in asthmatic school children. Fourteen children with asthma performed 2 histamine challenges with a 24-h time interval and 1 child performed 1 histamine challenge. The EMG signals were derived from surface electrodes. The logarithm of the EMG-activity-ratio (log EMGAR; mean peak-bottom ratio of respiratory muscle activity) was used as EMG parameter. The log EMGAR of the diaphragm (di) and the log EMGAR of the intercostal muscles (int) associated well with the histamine-induced fall in FEV(1) at 5% steps from the baseline value. After administration of salbutamol log EMGARdi and log EMGARint returned to baseline mean peak-bottom values (for all leads P<0.001). The EMGARdi and EMGARint values were reproducible at different levels of airflow limitation. This study showed that EMGARdi and EMGARint as a parameter for a change in electrical activity of the diaphragm and intercostal muscles associated well with FEV(1), was reversible after salbutamol and was reproducible at different levels of histamine-induced airflow limitation in asthmatic school children.

Role of serum cortisol levels in children with asthma

Decreased serum cortisol levels have been proposed to contribute to nocturnal airway obstruction. We investigated whether endogenous cortisol levels are lower, and also whether the 24-h cortisol variation is greater, in children with asthma than in control subjects and assessed the relationship between serum cortisol and nocturnal airflow limitation in children with asthma. Cortisol and FEV(1) were measured every 4 h over 24 h; blood eosinophils, airway responsiveness to methacholine and adenosine 5'-monophosphate (AMP) were measured at 0400 and 1600. Children with asthma had lower cortisol levels than did control subjects; at midnight the difference was significant. Subjects with nocturnal asthma (24-h FEV(1) variation > or =15%) had significantly lower cortisol levels than did control subjects at 0000, 0800, and 1200. A higher mean 24-h cortisol level in subjects with asthma was associated with a significantly higher FEV(1) as a percentage of the predicted value (FEV(1) %pred) at 0400, 0800, and 2000, yet not in control subjects. Higher 24-h cortisol variation was associated with lower FEV(1) %pred at all time points in both control subjects and subjects with nonnocturnal asthma. There was no significant association between the level or variation of cortisol and PD(20) methacholine (provocative dose of methacholine causing a 20% fall in FEV(1)), PD(20) AMP, or eosinophils. Our data suggest that lower cortisol levels contribute to both overall lower levels of FEV(1) especially at night. This may be due to a lack of suppression of airway inflammation.