A parent completed questionnaire to describe the patterns of wheezing and other respiratory symptoms in infants and preschool children

Self-reported respiratory and gastrointestinal outcomes in children with isolated congenital diaphragmatic hernia: A prospective multicentre study

OBJECTIVE

To evaluate medium-term self-reported respiratory and gastrointestinal (GI) outcomes in children with congenital diaphragmatic hernia (CDH).

DESIGN

Self-reported respiratory and GI outcomes correlated with prenatal severity indicators.

SETTING

Prospective study at three fetal medicine units.

POPULATION

Families of children prenatally diagnosed with isolated, left-sided CDH surviving for >1 year.

METHODS

Families received validated questionnaires for GI outcomes (Infant Gastroesophageal Reflux Questionnaire Revised, I-GERQ-R, for infants aged <2 years, or Paediatric Gastro-oesophageal Symptom and Quality of Life Questionnaire, PGSQ, for children aged aged 2-8 years or >9 years) and respiratory outcomes (preschool respiratory outcome questionnaire, for children aged ≤5 years, or the International Study of Asthma and Allergies in Childhood asthma questionnaire, for children aged 6-8 years or ≥9 years). Prenatal data collected from the medical records included lung size (percentage observed/expected lung-to-head ratio, O/E LHR %), liver position, fetal endoluminal tracheal occlusion (FETO) gestational age (GA) at delivery, and perinatal data included birthweight, location, patch repair and respiratory support.

MAIN OUTCOME MEASURES

The GI and respiratory scores were correlated with O/E LHR using linear and logistic regression models. Univariate analysis was used to evaluate associations with perinatal variables.

RESULTS

We obtained 142 responses from 342 families (representing a response rate of 45%). The baseline characteristics of participants and non-participants were comparable. No correlations between perinatal variables and respiratory or GI scores were identified. Children aged ≤5 years with lower O/E LHR values reported higher respiratory scores (P = 0.0175); this finding was not reported in older children. Overall, the children who underwent FETO (n = 51) had GI (P = 0.290) and respiratory (P = 0.052) scores that were comparable with those of children who were expectantly managed.

CONCLUSIONS

Families and children with prenatally diagnosed CDH reported fewer respiratory symptoms with increasing age. There was no correlation between O/E LHR or the use of FETO and self-reported outcomes.

Association of antenatal or neonatal SARS-COV-2 exposure with developmental and respiratory outcomes, and healthcare usage in early childhood: a national prospective cohort study

Background

Perinatal exposure to SARS-CoV-2 may affect neurodevelopment before 12 months of age, but longer-term outcomes remain unknown. We examined whether antenatal or neonatal SARS-CoV-2 exposure compared with non-exposure is associated with neurodevelopment, respiratory symptoms, and health care usage in early childhood.

Methods

This prospective national population-based cohort study was conducted in England and Wales, United Kingdom. We enrolled term-born children (≥37 weeks' gestation) with and without antenatal or neonatal exposure to SARS-CoV-2 infection by approaching parents of eligible children who were cared for in 87 NHS hospitals. Potential participants were identified through the national active surveillance studies of pregnant women and newborn infants hospitalised with confirmed SARS-CoV-2 infection conducted through the UK Obstetric Surveillance System and the British Paediatric Surveillance Unit. We defined antenatal and neonatal SARS-CoV-2 exposure as infants born to mothers hospitalised with confirmed SARS-CoV-2 infection between 14 + 0 and 36 + 6 weeks gestation and infants admitted to hospital with confirmed SARS-CoV-2 infection within the first 28 days after birth. Children born preterm or with major congenital anomaly or who were not residing in the UK were excluded. We assessed children's development (Ages and Stages Questionnaire 3rd Edition (ASQ-3); Ages and Stages Questionnaire Social-Emotional 2nd Edition (ASQ:SE-2)), respiratory symptoms (Liverpool Respiratory Symptom Questionnaire (LRSQ)) and health care usage (parent-completed questionnaire) at 21-32 months of age. Primary outcome: total ASQ-3 score, converted to z-scores. Secondary outcomes: ASQ:SE-2 z-scores; risk of delay in ASQ-3 domains; total LRSQ scores, converted to z-scores. Analyses were adjusted for children's age, sex, maternal ethnicity, parental education, and index of multiple deprivation.

Findings

Between October 20, 2021 and January 27, 2023, we approached 668 and 1877 families out of 712 and 1917 potentially eligible participants in the exposed and comparison cohort. Of the 125 and 306 participants who were enrolled to the exposed and comparison cohort 121 and 301 participants completed the questionnaires and 96 and 243 participants were included in the analysis. In the age adjusted analysis, the mean total ASQ-3 z-score was lower in the exposed than the comparison cohort (-0.3, 95% CI: -0.6 to -0.05), however, when adjusted for sex, parental education, ethnicity and IMD quintile, there was no significant difference (difference in mean z-score = -0.2 95% CI: -0.5 to 0.03). SARS-CoV-2 exposure was associated with increased risk of delayed personal-social skills (odds ratio = 3.81; 95% CI: 1.07-13.66), higher ASQ:SE-2 total z-scores (difference in mean z-score = 0.4; 95% CI: 0.2-0.6) and increased risk of delayed social-emotional development (OR = 3.58, 95% CI: 1.30-9.83), after adjusting for sex, age at assessment, parental education, ethnicity and IMD quintile. The exposed cohort had a higher mean total LRSQ z-score than the comparison cohort (0.3 95% CI: 0-0.6) and higher inpatient (38% vs. 21%, p = 0.0001), outpatient (38% vs. 30%, p = 0.0090), and General Practitioner appointments (60% vs. 50%, p = 0.021) than the comparison cohort, after adjusting for sex, age at assessment, parental education, ethnicity and IMD quintile. No differences in other secondary outcomes between the exposed and comparison cohorts were found.

Interpretation

Although the exposed cohort did not differ from the comparison cohort on the primary outcome, total ASQ-3 score, the exposed cohort were at greater risk of delayed social-emotional development, had a greater prevalence of respiratory symptoms and increased health care usage relative to the comparison cohort. The study is limited by the smaller sample size due to the low response rate and lack of clinical developmental assessments. Given the association of poor social-emotional development with antenatal or neonatal SARS-CoV-2 exposure, developmental screening, and follow-up of children with confirmed antenatal or neonatal SARS-CoV-2 infection may be warranted to identify those in need of early intervention.

Funding

Action Medical Research for Children.

Risk factors for poorer respiratory outcomes in adolescents and young adults born preterm

RATIONALE

The respiratory outcomes for adult survivors of preterm birth in the postsurfactant era are wide-ranging with prognostic factors, especially those encountered after the neonatal period, poorly understood.

OBJECTIVES

To obtain comprehensive 'peak' lung health data from survivors of very preterm birth and identify neonatal and life-course risk factors for poorer respiratory outcomes in adulthood.

METHODS

127 participants born ≤32 weeks gestation (64%, n=81 with bronchopulmonary dysplasia (BPD), initially recruited according to a 2 with-BPD:1 without-BPD strategy), and 41 term-born controls completed a lung health assessment at 16-23 years, including lung function, imaging and symptom review. Risk factors assessed against poor lung health included neonatal treatments, respiratory hospitalisation in childhood, atopy and tobacco smoke exposure.

MEASUREMENTS AND MAIN RESULTS

Young adults born prematurely had greater airflow obstruction, gas trapping and ventilation inhomogeneity, in addition to abnormalities in gas transfer and respiratory mechanics, compared with term. Beyond lung function, we observed greater structural abnormalities, respiratory symptoms and inhaled medication use. A previous respiratory admission was associated with airway obstruction; mean forced expiratory volume in 1 s/forced vital capacity z-score was -0.561 lower after neonatal confounders were accounted for (95% CI -0.998 to -0.125; p=0.012). Similarly, respiratory symptom burden was increased in the preterm group with a respiratory admission, as was peribronchial thickening (6% vs 23%, p=0.010) and bronchodilator responsiveness (17% vs 35%, p=0.025). Atopy, maternal asthma and tobacco smoke exposure did not influence lung function or structure at 16-23 years in our preterm cohort.

CONCLUSIONS

Even after accounting for the neonatal course, a respiratory admission during childhood remained significantly associated with reduced peak lung function in the preterm-born cohort, with the largest difference seen in those with BPD. A respiratory admission during childhood should, therefore, be considered a risk factor for long-term respiratory morbidity in those born preterm, especially for individuals with BPD.

Outcomes at 7 Years of Age of Former Very Preterm Neonates with Repeated Surfactant Treatment for Prolonged Respiratory Distress in the Neonatal Period

This study aimed at evaluating the 7-year outcomes of 118 very preterm newborns (VPNs, gestational age = 26 ± 1.4 w) involved in a randomized controlled trial. They presented neonatal respiratory distress (RDS), requiring ventilation for 14 ± 2 days post-natal age (PNA). A repeated instillation of 200 mg/kg poractant alfa (SURF) did not improve early bronchopulmonary dysplasia, but the SURF infants needed less re-hospitalization than the controls for respiratory problems at 1- and 2-year PNA. There was no growth difference at 7.1 ± 0.3 years between 41 SURF infants and 36 controls (80% of the eligible children), and 7.9% SURF infants vs. 28.6% controls presented asthma (p = 0.021). The children underwent cognitive assessment (WISC IV) and pulmonary function testing (PFT), measuring their spirometry, lung volume, and airway resistance. The spirometry measures showed differences (p < 0.05) between the SURF infants and the controls (mean ± standard deviation (median z-score)) for FEV1 (L/s) (1.188 ± 0.690(-0.803) vs. 1.080 ± 0.243 (-1.446)); FEV1 after betamimetics (1.244 ± 0.183(-0.525) vs. 1.091 ± 0.20(-1.342)); FVC (L) (1.402 ± 0.217 (-0.406) vs. 1.265 ± 0.267 (-1.141)), and FVC after betamimetics (1.452 ± 0.237 (-0.241) vs. 1.279 ± 0.264 (-1.020)). PFT showed no differences in the volumes or airway resistance. The global IQ median (interquartile range) was 89 (82:99) vs. 89 (76:98), with 61% of the children >85 in both groups. Repeated surfactant treatment in VPNs presenting severe RDS led to the attenuation of early lung injuries, with an impact on long-term pulmonary sequelae, without differences in neurodevelopmental outcomes.

Effect of SARS-CoV-2 infection in neonates or in pregnancy on developmental outcomes at 21-24 months (SINEPOST): study protocol for a prospective cohort study

INTRODUCTION

Exposure to SARS-CoV-2 during pregnancy or in the neonatal period may impact fetal or neonatal brain development either through direct central nervous system infection or indirectly through the adverse effects of viral infection-related inflammation in the mother or newborn infant. This study aims to determine whether there are early neurodevelopmental effects of SARS-CoV-2 infection.

METHODS AND ANALYSIS

We will conduct a prospective national population-based cohort study of children aged 21-24 months who were born at term (≥37 weeks' gestation) between 1 March 2020 and 28 February 2021 and were either antenatally exposed, neonatally exposed or unexposed (comparison cohort) to SARS-CoV-2. Nationally, hospitals will identify and approach parents of children eligible for inclusion in the antenatally and neonatally exposed cohorts using information from the UK Obstetric Surveillance System (UKOSS) and British Paediatric Surveillance Unit (BPSU) national surveillance studies and will identify and approach eligible children for the comparison cohort through routine birth records. Parents will be asked to complete questionnaires to assess their child's development at 21-24 months of age. Outcome measures comprise the Ages and Stages Questionnaire, Third Edition (ASQ-3), Ages and Stages Questionnaire Social-Emotional, Second Edition (ASQ-SE-2), Liverpool respiratory symptoms questionnaire and questionnaire items to elicit information about healthcare usage. With parental consent, study data will be linked to routine health and education records for future follow-up. Regression models will compare ASQ-3 and ASQ-SE-2 scores and proportions, frequency of respiratory symptoms and healthcare usage between the exposed and comparison cohorts, adjusting for potential confounders.

ETHICS AND DISSEMINATION

Ethics approval was obtained from the London-Westminster Research Ethics Committee. Findings will be disseminated in scientific conference presentations and peer-reviewed publications.

ISRCTN REGISTRATION NUMBER

ISRCTN99910769.

Single-Center-Single-Blinded Clinical Trial to Evaluate the Efficacy of a Nutraceutical Containing Boswellia Serrata, Bromelain, Zinc, Magnesium, Honey, Tyndallized Lactobacillus Acidophilus and Casei to Fight Upper Respiratory Tract Infection and Otitis Media

Some nutraceuticals have been studied as supportive treatment for fighting upper respiratory tract infection and middle ear disease. Our study aims at evaluating the effect of a specific oral supplementation in the treatment of pediatric otits media. The subjects were randomly assigned by the physician (single-blinded study) to one of three groups: Control Group (CG), Treatment Group 1 (TG1), or Treatment Group 2 (TG2). Both TG were treated with Flogostop Duo (for 20 days—TG1 or 30 days—TG2) in combination with the standard treatment, while CG underwent standard treatment only. The standard treatment was nasal aerosol with Fluticasone and Mucolytic, and nasal washing with hypertonic solution. All patients were analyzed by otoscopy, impedance, fibroscopy, and pure auditory test at the baseline (T0), after 20 days (T1) and 35 days (T2). 120 children were included in the study, 40 in the CG, 40 in the TG1, and 40 in the TG2. Both TG1 and TG2 presented statistically significant differences with respect to controls in otoscopy, impedance, fibroscopy, and PTA at T2. The otoscopy improved at T2 with statistically significant value only in TG2. The impedance and fibroscopy improved at T1 both in TG1 and TG2 compared to CG. A statistically significant improvement was observed in TG2 at T2 in comparison to both CG and TG1. Statistically significant differences were observed in PTA at T2 only compared with controls. This study confirmed the efficacy of nutraceutical as supporting therapy in the upper respiratory tract infection in children. In particular, the supplement containing Boswellia serrata and Bromelain, which are molecules with strong anti-inflammatory and pain-control capacities, could add the benefit without the adverse effects which are related to NSAID use.

Humidified and standard oxygen therapy in acute severe asthma in children (HUMOX): A pilot randomised controlled trial

Background

Oxygen (O2) is a mainstay of treatment in acute severe asthma but how it is administered varies widely. The objectives were to examine whether a trial comparing humidified O2 to standard O2 in children is feasible, and specifically to obtain data on recruitment, tolerability and outcome measure stability.

Methods

Heated humidified, cold humidified and standard O2 treatments were compared for children (2–16 years) with acute severe asthma in a multi-centre, open, parallel, pilot randomised controlled trial (RCT). Multiple outcomes were assessed.

Results

Of 258 children screened, 66 were randomised (heated humidified O2 n = 25; cold humidified O2 n = 21; standard O2 n = 20). Median (IQR) length of stay (hours) in hospital was 37.9 (29.1), 52 (35.4) and 49.1 (29.7) for standard, heated humidified and cold humidified respectively and time (hours) on O2 was 15.9 (9.4), 13.6 (14.9) and 13.1 (14.9) for the three groups respectively. The mean (standard deviation) time (hours) taken to step down nebulised to inhaled treatment was 5.6 (14.3), 35.1 (28.2) and 32.7 (20.1). Asthma Severity Score decreased in all three groups similarly, although missing data prevented complete analysis. Humidified O2 was least well tolerated with eight participants discontinuing their randomised treatment early. An important barrier to recruitment was research nurse availability.

Conclusion

Although, the results of this pilot study should not be extrapolated beyond the study sample and inferential conclusions should not be drawn from the results, this is the first RCT to compare humidified and standard O2 therapy in acute severe asthmatics of any age. These findings and accompanying screening data show that a large RCT of O2 therapy is feasible. However, challenges associated with randomisation and data collection should be addressed in any future trial design.

Rhinovirus bronchiolitis, maternal asthma, and the development of asthma and lung function impairments

BACKGROUND

Children with a history of rhinovirus (RV) positive bronchiolitis have a high risk of developing subsequent asthma. Maternal asthma might also increase this risk. The aim of this study was to investigate the combined effects of hospitalization for RV positive bronchiolitis in infancy and a history of maternal asthma on the development of asthma at preschool age.

METHODS

This is a prospective cohort study of 139 preschool-aged children, with a history of hospital admission for bronchiolitis in infancy, followed-up to ascertain asthma and asthma-like symptoms, skin prick allergy test positivity, and lung function measured pre- and post-bronchodilator using impulse oscillometry.

RESULTS

Children with a past hospitalization for RV positive bronchiolitis (42.4% of all) and a history of maternal asthma (36.7% of all) had the greatest prevalence and risk ratio (RR) for doctor-diagnosed asthma (prevalence 81.8% and RR 2.10, 95% confidence interval [CI] 1.37-3.19, p = .001), use of inhaled corticosteroids (68.2% and RR 2.17, 95% CI 1.19-3.99, p = .001) and short-acting β-agonists in the last 12 months (95.2% and RR 1.49, 95% CI 1.17-1.89, p = .001), as compared to those with RV negative bronchiolitis and no maternal asthma history. More children in this group had an abnormal airway resistance (33.3% and adjusted risk ratio [aRR] 3.11, 95% CI 1.03-9.47, p = .045) and reactance (27.8% and aRR 2.11, 95% CI 1.06-4.26, p = .035) at 5 Hz, as compared to those with RV negative bronchiolitis and no maternal asthma history.

CONCLUSION

Hospitalization for RV positive bronchiolitis in early life combined with a history of maternal asthma identifies a subgroup of children with a high asthma burden while participants with only one of the two risk factors had intermediate risk for asthma.

Lung abnormalities do not influence aerobic capacity in school children born preterm

PURPOSE

Children born preterm have impaired lung function and altered lung structure. However, there are conflicting reports on how preterm birth impacts aerobic exercise capacity in childhood. We aimed to investigate how neonatal history and a diagnosis of bronchopulmonary dysplasia (BPD) impact the relationship between function and structure of the lung, and aerobic capacity in school-aged children born very preterm.

METHODS

Preterm children (≤ 32 w completed gestation) aged 9-12 years with (n = 38) and without (n = 35) BPD, and term-born controls (n = 31), underwent spirometry, lung volume measurements, gas transfer capacity, a high-resolution computer tomography (CT) scan of the chest, and an incremental treadmill exercise test.

RESULTS

Children born preterm with BPD had an elevated breathing frequency to tidal volume ratio compared to term controls (76% vs 63%, p = 0.002). The majority (88%) of preterm children had structural changes on CT scan. There were no differences in peak V̇O₂ (47.1 vs 47.7 mL/kg/min, p = 0.407) or oxygen uptake efficiency slope when corrected for body weight (67.6 vs 67.3, p = 0.5) between preterm children with BPD and term controls. There were no differences in any other exercise outcomes. The severity of structural lung disease was not associated with exercise outcomes in this preterm population.

CONCLUSION

Children born preterm have impaired lung function, and a high prevalence of structural lung abnormalities. However, abnormal lung function and structure do not appear to impact on the aerobic exercise capacity of preterm children at school age.

A systematic review of patient-reported outcome measures (PROMs) in cystic fibrosis

BACKGROUND

To determine patient-reported outcome measures (PROMs) which may be suitable for incorporation into the Australian Cystic Fibrosis Data Registry (ACFDR) by identifying PROMs administered in adult and paediatric cystic fibrosis (CF) populations in the last decade.

METHODS

We searched MEDLINE, EMBASE, Scopus, CINAHL, PsycINFO and Cochrane Library databases for studies published between January 2009 and February 2019 describing the use of PROMs to measure health-related quality of life (HRQoL) in adult and paediatric patients with CF. Validation studies, observational studies and qualitative studies were included. The search was conducted on 13 February 2019. The COnsensus-based Standards for the selection of health Measurement INstruments Risk of Bias Checklist was used to assess the methodological quality of included studies.

RESULTS

Twenty-seven different PROMs were identified. The most commonly used PROMs were designed specifically for CF. Equal numbers of studies were conducted on adult (32%, n=31), paediatric (35%, n=34) and both (27%, n=26) populations. No PROMs were used within a clinical registry setting previously. The two most widely used PROMs, the Cystic Fibrosis Questionnaire-Revised (CFQ-R) and the Cystic Fibrosis Quality of Life Questionnaire (CFQoL), demonstrated good psychometric properties and acceptability in English-speaking populations.

DISCUSSION

We found that although PROMs are widely used in CF, there is a lack of reporting on the efficacy of methods and timepoints of administration. We identified the CFQ-R and CFQoL as the most suitable for incorporation in the ACFDR as they captured significant effects of CF on HRQoL and were reliable and valid in CF populations. These PROMs will be used in a further qualitative study assessing patients' with CF and clinicians' perspectives toward the acceptability and feasibility of incorporating a PROM in the ACFDR.

PROSPERO REGISTRATION NUMBER

CRD42019126931.

Change in exhaled nitric oxide during peanut challenge is related to severity of reaction

BACKGROUND

Peanut allergy affects 3% of Australian children and has a higher risk of anaphylaxis than most food allergies. Predicting who is likely to develop anaphylaxis is still an inexact science. The fraction of exhaled nitric oxide (FeNO) shows promise as a biomarker involved in peanut allergy, as nitric oxide plays a role in inhibiting mast cell degranulation which is relevant in anaphylaxis, where mast cell degranulation plays a mediator role. The aim of this study was to assess the change in FeNO in children during peanut challenge.

METHODS

Thirty-six children aged from 5 to 17 years were recruited for open-labelled peanut challenge. Participants had skin prick test to peanut performed, and serum collected for Ara h2 specific IgE and peanut specific IgE. FeNO was measured by portable device (NIOX VERO) prior to and throughout the peanut challenge.

RESULTS

When grouped according to reaction type at peanut challenge (anaphylaxis, clinical allergy not anaphylaxis and tolerant), there were significant differences in the mean change in FeNO measurement between the anaphylaxis group and the clinical allergy, not anaphylaxis group (p = 0.005), and between the anaphylaxis group and tolerant group (p < 0.0001).

CONCLUSIONS

FeNO decreased more significantly in those who subsequently developed anaphylaxis than in those with clinical allergy, not anaphylaxis or negative peanut challenge (tolerance). As a bedside test that can be used in children, it has potential for further research into mechanisms of anaphylaxis in food allergy and potentially assists in predicting an imminent anaphylactic reaction in some patients.Trial registration ClinicalTrials.gov: PEAnut Anaphylaxis Predictors (PEAAP) NCT02424136.

Pepsin as a Marker of Reflux Aspiration in Children With Esophageal Atresia: A Pilot Study

Background: Reflux aspiration secondary to gastroesophageal reflux disease (GERD) is one of the causes of chronic gastrointestinal and respiratory morbidity in children with esophageal atresia (EA). Currently there are no simple, validated non-invasive tests for the diagnosis of reflux aspiration in children. Objectives: The aim of this pilot study was to investigate pepsin detected in exhaled breath condensate (EBC) and saliva as a potential non-invasive marker of reflux aspiration in children with EA. Methods: EBC and saliva samples were prospectively collected from children with EA aged between 5 and 18 years attending a multidisciplinary EA Clinic. Pepsin in the samples was assayed by two methods, a commercial lateral flow device, the Peptest™ and an enzyme-linked immunosorbent assay (ELISA) and correlated with validated gastrointestinal and respiratory symptom questionnaires and objective measures of GERD and respiratory function. Results: EBC were collected from 18 children with EA, 15/18 also provided salivary samples. Pepsin was not detected in any of the EBC samples using the Peptest™ and only 1/14 (7.1%) samples by the ELISA. However, pepsin was detected in 33 and 83% of saliva samples when analyzed with Peptest™ and the ELISA respectively. Salivary pepsin levels were significantly higher in children with reflux symptoms or wheeze. Pepsin was detected by the Peptest™ in the saliva of 5/5 (100%) children with histological evidence of reflux esophagitis compared with 0/2 (0%) in children with normal histology (p = 0.048). Conclusions: Salivary pepsin was detected in a large proportion of children with EA and was significantly associated with GERD symptoms or wheeze. The role of salivary pepsin as a potential non-invasive marker of reflux aspiration in children with EA needs further validation in future studies with larger cohorts.

High incidence of respiratory disease in Australian infants despite low rate of maternal cigarette smoking

AIM

The burden of wheezing illnesses in Australian infants has not been documented since the success of initiatives to reduce maternal cigarette smoking. We aimed to determine the incidence of wheeze and related health-care utilisation during the first year of life among a contemporary Australian birth cohort.

METHODS

A birth cohort of 1074 infants was assembled between 2010 and 2013. Parents completed questionnaires periodically. Several non-exclusive infant respiratory disease phenotypes were defined, including any wheeze, wheeze with shortness of breath and recurrent wheeze. Skin prick testing was performed to determine atopic wheeze. Health-care utilisation for respiratory disease was determined from questionnaires and hospital medical records.

RESULTS

Retention to 1 year was 840/1074 (83%). The incidence of any wheeze was 51.8% (95% confidence interval (CI) 48.3-55.2%), wheeze with shortness of breath 20.6% (95% CI 17.9-23.5), recurrent wheeze 19.4% (95% CI 16.8-22.2) and atopic wheeze 6% (95% CI 4.6-7.8). Respiratory illness resulted in primary health-care utilisation in 82.2% (95% CI 79.3-84.8) of participants and hospital presentation in 8.8% (95% CI 7.2-10.6). Maternal smoking during pregnancy was uncommon (15.7%) and was not associated with wheeze or health resource utilisation. Male gender, familial atopy and asthma and smaller household size were associated with a higher incidence of wheeze.

CONCLUSIONS

The incidence of wheezing illness among Australian infants remains high despite relatively low rates of maternal smoking during pregnancy. The majority of the health-care burden is borne by primary health-care services. Further research is required to inform novel prevention strategies.

Upper Airway Pathology Contributes to Respiratory Symptoms in Children Born Very Preterm

OBJECTIVE

To evaluate the role of upper airway dysfunction, indicated by altered vocal quality (dysphonia), on the respiratory symptoms of children surviving very preterm birth.

STUDY DESIGN

Children born <32 weeks of gestation participated in 2 separate assessments during midchildhood. The first visit assessed voice quality by a subjective evaluation using the Consensus Auditory-Perceptual Evaluation of Voice and a computerized analysis of the properties of the voice via the Acoustic Voice Quality Index. The second assessment recorded parentally reported respiratory symptoms and measures of lung function, including spirometry, lung volumes, oscillatory mechanics, and a cardiopulmonary exercise test.

RESULTS

Preterm children (n = 35; median gestation 24.3 weeks) underwent paired voice and lung assessments at approximately 11 years of age. Preterm children with dysphonia (n = 25) reported significantly more respiratory symptoms than those with normal voices (n = 10) including wheeze (92% vs 40%; P = .001) and asthma diagnosed by a physician (60% vs 10%; P = .007). Lung function outcomes were generally not different between the dysphonic group and the group with normal voice (P > .05), except for the oscillatory mechanics measures, which were all at least 0.5 z score lower in the dysphonic group (Xrs₈ mean difference = -0.91 z scores, P = .003; f_res = 1.06 z scores, P = .019; AX = -0.87 z scores, P = .010; Rrs₈ = 0.63 z scores, P = .068).

CONCLUSIONS

The upper airway may play a role in the respiratory symptoms experienced by some very preterm children and should be considered by clinicians, especially when symptoms are in the presence of normal lung function and are refractory to treatment.

How Maternal BMI Modifies the Impact of Personalized Asthma Management in Pregnancy

BACKGROUND

Maternal asthma is associated with perinatal complications and respiratory illness in offspring. Obesity increases asthma exacerbation risk in pregnancy and risk of wheeze in offspring.

OBJECTIVES

In this secondary analysis of a randomized controlled trial, we investigated the influence of maternal body mass index, gestational weight gain (GWG), and fractional exhaled nitric oxide (F_ENO)-based management on asthma exacerbations in pregnancy and offspring wheeze.

METHODS

A total of 220 women were randomized to asthma treatment adjustment according to symptoms (control group), or F_ENO and symptoms (F_ENO group). Exacerbations were recorded prospectively. Height and weight were measured at baseline, and in late pregnancy. GWG was categorized according to Institute of Medicine guidelines. A validated parent-completed questionnaire assessed infant wheeze-related outcomes.

RESULTS

F_ENO-based management was associated with a significantly lower incidence rate ratio for maternal exacerbations in nonobese mothers (0.52, 95% confidence interval [CI], 0.31-0.88, P = .015, n = 129), and women with GWG within recommendations (0.35, 95% CI, 0.12-0.96, P = .042, n = 43), but not for obese mothers (0.59, 95% CI, 0.32-1.08, P = .089, n = 88), or women with excess GWG (0.58, 95% CI, 0.32-1.04, P = .07, n = 104). Recurrent bronchiolitis occurred in 5.3% (n = 1) of infants born to non-overweight mothers, 16.7% (n = 3) of infants of overweight mothers, and 21.7% (n = 5) of infants of obese mothers in the control group. In the F_ENO group, 2 infants of obese mothers had recurrent bronchiolitis (7.1%, P = .031).

CONCLUSIONS

The benefits of F_ENO-based management are attenuated among obese mothers and those with excess GWG, indicating the importance of weight management in contributing to improved asthma management in pregnancy.

Increased prevalence of expiratory flow limitation during exercise in children with bronchopulmonary dysplasia

Evidence regarding the prevalence of expiratory flow limitation (EFL) during exercise and the ventilatory response to exercise in children born preterm is limited. This study aimed to determine the prevalence of EFL as well as contributing factors to EFL and the ventilatory response to exercise in preterm children with and without bronchopulmonary dysplasia (BPD).

Preterm children (≤32 weeks gestational age) aged 9–12 years with (n=64) and without (n=42) BPD and term controls (n=43), performed an incremental treadmill exercise test with exercise tidal flow–volume loops.

More preterm children with BPD (53%) had EFL compared with preterm children without BPD (26%) or term controls (28%) (p<0.05). The presence of EFL was independently associated with decreased forced expiratory volume in 1 s/forced vital capacity z-score and lower gestational age (p<0.05). There was no difference in peak oxygen uptake between preterm children with BPD and term controls (48.0 versus 48.4 mL·kg⁻¹·min⁻¹; p=0.063); however, children with BPD had a lower tidal volume at peak exercise (mean difference −27 mL·kg⁻¹, 95% CI −49– −5; p<0.05). Children born preterm without BPD had ventilatory responses to exercise similar to term controls.

Expiratory flow limitation is more prevalent in children born preterm with BPD and is associated with airway obstruction and a lower gestational age.

Children born preterm have an increased prevalence of expiratory limitation during exercise associated with reduced lung function and lower gestational agehttp://ow.ly/jLsk30leOVI

Lung function trajectories throughout childhood in survivors of very preterm birth: a longitudinal cohort study

BACKGROUND

Data on longitudinal respiratory follow-up after preterm birth in the surfactant era are scarce and of increasing importance, with concerns that preterm survivors are destined for early onset chronic obstructive airway disease. We aimed to comprehensively assess lung function longitudinally from early childhood to mid-childhood in very preterm children (≤32 weeks gestation), and to explore factors negatively impacting on lung function trajectories.

METHODS

Preterm children (with and without bronchopulmonary dysplasia) and healthy term children as controls were studied. All preterm participants were born at 32 weeks' gestation or earlier at King Edward Memorial Hospital, Perth, WA, Australia, between 1997 and 2003. Bronchopulmonary dysplasia was defined as at least 28 days of supplemental oxygen requirement as assessed at 36 weeks' post-menstrual age. Spirometry, oscillatory mechanics, gas exchange, lung volumes, and respiratory symptoms were assessed at three visits, two in early childhood (4-8 years) and one in mid-childhood (9-12 years). CT of the chest was done in preterm children in mid-childhood. Respiratory symptoms were documented via questionnaire at each visit. Data were analysed longitudinally using linear mixed models.

FINDINGS

200 very preterm children (126 with bronchopulmonary dysplasia and 74 without bronchopulmonary dysplasia) and 67 healthy term control children attended 458 visits between age 4 and 12 years. Chest CT was done on 133 preterm children at a mean age of 10·9 (SD 0·6) years. Preterm children, with and without bronchopulmonary dysplasia, had declines in spirometry z-scores over time compared with controls: forced expiratory volume in 1 s (FEV₁), forced expiratory flow at 25-75% of the pulmonary volume, and FEV₁/forced vital capacity all declined by at least 0·1 z-score per year in children with bronchopulmonary dysplasia (all p<0·001). Respiratory mechanics and gas exchange also deteriorated over time in children with bronchopulmonary dysplasia (relative to term controls, respiratory system reactance at 8 Hz decreased by -0·05 z-score per year [95% CI -0·08 to -0·01; p=0·006] and diffusing capacity of the lungs for carbon monoxide decreased by -0·03 z-score per year [95% CI -0·06 to -0·01; p=0·048]). Preterm children with bronchial wall thickening on chest CT (suggestive of inflammation) had bigger decreases in spirometry outcomes through childhood. For example, children with bronchial wall thickening on chest CT had an FEV₁ z-score decline of -0·61 (95% CI -1·03 to-0·19; p=0·005) more than those without. Similarly, children exposed to tobacco smoke, those with earlier gestation, or those requiring more neonatal supplemental oxygen declined at a faster rate.

INTERPRETATION

Lung function trajectories are impaired in survivors of very preterm birth. Survivors with bronchopulmonary dysplasia, ongoing respiratory symptoms, or CT changes reflecting inflammation have the poorest trajectories and might be at increased risk of lung disease in later life. Close targeted pulmonary follow-up of these individuals is necessary.

FUNDING

National Health and Medical Research Council grants APP634519, APP1073301 (to SJS), APP1077691 (to JJP), and APP1025550 (to GLH), Princess Margret Hospital Foundation, and Raine Medical Foundation.

Managing Asthma in Pregnancy (MAP) trial: FENO levels and childhood asthma

BACKGROUND

The single-center double-blind, randomized controlled Managing Asthma in Pregnancy (MAP) trial in Newcastle, Australia, compared a treatment algorithm using the fraction of exhaled nitric oxide (FENO) in combination with asthma symptoms (FENO group) against a treatment algorithm using clinical symptoms only (clinical group) in pregnant asthmatic women (Australian New Zealand Clinical Trials Registry, no. 12607000561482). The primary outcome was a 50% reduction in asthma exacerbations during pregnancy in the FENO group. However, the effect of FENO-guided management on the development of asthma in the offspring is unknown.

OBJECTIVE

We sought to investigate the effect of FENO-guided asthma management during pregnancy on asthma incidence in childhood.

METHODS

A total of 179 mothers consented to participate in the Growing into Asthma (GIA) double-blind follow-up study with the primary aim to determine the effect of FENO-guided asthma management on childhood asthma incidence.

RESULTS

A total of 140 children (78%) were followed up at 4 to 6 years of age. FENO-guided as compared to symptoms-only approach significantly reduced doctor-diagnosed asthma (25.9% vs 43.2%; odds ratio [OR], 0.46, 95% CI, 0.22-0.96; P = .04). Furthermore, frequent wheeze (OR, 0.27; 95% CI, 0.09-0.87; P = .03), use of short-acting β-agonists (OR, 0.49; 95% CI, 0.25-0.97; P = .04), and emergency department visits for asthma (OR, 0.17; 95% CI, 0.04-0.76; P = .02) in the past 12 months were less common in children born to mothers from the FENO group. Doctor-diagnosed asthma was associated with common risk alleles for early onset asthma at gene locus 17q21 (P = .01 for rs8069176; P = .03 for rs8076131), and higher airways resistance (P = .02) and FENO levels (P = .03). A causal mediation analysis suggested natural indirect effects of FENO-guided asthma management on childhood asthma through "any use" and "time to first change in dose" of inhaled corticosteroids during the MAP trial (OR: 0.83; 95% CI: 0.59-0.99, and OR: 0.90; 95% CI: 0.70-1.03, respectively).

CONCLUSIONS

FENO-guided asthma management during pregnancy prevented doctor-diagnosed asthma in the offspring at preschool age, in part mediated through changes in use and dosing of inhaled corticosteroids during the MAP trial.

Effect of fetal and infant growth on respiratory symptoms in preterm-born children

OBJECTIVES

Fetal growth and rapid postnatal weight gain are associated with adverse respiratory outcomes in childhood. However, the preterm-born population is less well studied. We assessed if the increased respiratory symptoms associated with altered fetal growth and infant weight gain were mediated by early factors.

STUDY DESIGN

We used data from our cohort of preterm- and term-born (n = 4284 and 2865) children, aged 1-10 years. Respiratory outcomes obtained from a respiratory questionnaire were regressed on measures of fetal growth and infant weight gain, defined as >0.67 SD change in fetal measurement or weight between birth and nine months of age, then adjusted for covariates. We used mediation analysis to investigate which variables were effect modifiers.

RESULTS

Accelerated fetal growth between the 1st trimester and birth (OR 2.01; 95%CI 1.25, 2.32), and between the 2nd trimester and birth (1.60; 1.15, 2.22) was associated with increased wheeze-ever in preterm-born children. Rapid infant weight gain was associated with increased wheeze-ever (1.22; 1.02, 1.45); children born ≤32 weeks' gestation exhibiting rapid weight gain had fivefold higher risk of wheeze-ever compared to term-born without weight gain. Current maternal smoking and gestational age were identified as candidate mediating effects.

CONCLUSIONS

Our study suggested that antenatal and postnatal growth rates are important for future respiratory health in preterm-born children, and that their effects may be mediated by modifiable factors. Minimizing exposure to environmental pollutants, especially maternal tobacco smoking, may improve outcomes.

Determining the outcomes of interventions to prevent respiratory syncytial virus disease in children: what to measure?

Respiratory syncytial virus (RSV) is the most common cause of viral acute lower respiratory tract illness (LRTI) in young children, and a major cause of hospital admissions and health-care utilisation globally. Substantial efforts have been made to develop RSV vaccines and vaccine-like monoclonal antibodies to prevent acute RSV LRTI. Prevention of acute disease could improve long-term lung health, with potential effects on wheezing, asthma, and chronic lung disease. This Personal View describes assessments that should be initiated during clinical trials and continued after licensure to fully evaluate the effect of RSV preventive interventions. These assessments include recording the incidence of RSV-specific LRTI and all-cause LRTI through two RSV seasons, and assessment of the prevalence and severity of recurrent wheezing or asthma in children aged up to 6 years. Standardised assessments in diverse settings are needed to fully determine the effect of interventions for the prevention of RSV disease.

Clinical Outcome for Congenital Diaphragmatic Hernia at the Age of 1 Year in the Era of Fetal Intervention

BACKGROUND

Congenital diaphragmatic hernia (CDH) is an abnormal development of the diaphragm leading to high neonatal mortality and morbidity. Beyond the neonatal period, prospective data on overall long-term outcome in CDH survivors is scarce. In particular, for those treated with fetoscopic endoluminal tracheal occlusion (FETO), a promising new technique to increase survival chances for severe cases, the outcomes are even less documented.

AIM

To prospectively document the clinical outcome of CDH at 1 year including FETO-treated infants in relation to ante- and postnatal variables.

METHODS

A single-centre prospective clinical follow-up at 1 year of age included a standardised respiratory questionnaire.

RESULTS

Thirty-four CDH survivors were included, 10 of which were FETO-treated infants. At 1 year, the median weight z score was -1.50 (interquartile range [IQR]: -2.45 to -0.88) and 10/34 were "failure to thrive" (FTT) cases. Gastro-intestinal (GI) problems at 1 year were mainly related to gastro-oesophageal reflux (16/34) with a high need for tube feeding in the first year (9/34). Tachypnoea was present in 10/29 (34%) and 8/34 (24%) were on chronic inhaled medication. The median total respiratory symptom score was 20 (IQR: 13-32) and correlated with the number of neonatal ventilation days (p = 0.048). Hospital re-admission occurred in 19/34 infants (56%), and was for respiratory problems in almost half of them (8/19).

CONCLUSION

In this CDH cohort, morbidity at 1 year was determined more by GI problems and FTT than respiratory morbidity. The respiratory questionnaire may, however, have underestimated the respiratory morbidity since respondents had a 1-in-4 chance to have persistent tachypnoea and be on chronic inhalation therapy.

Respiratory function and symptoms in young preterm children in the contemporary era

OBJECTIVE

To determine the relationships between respiratory symptoms, lung function, and neonatal events in young preterm children.

METHODS

Preterm children (<32 w gestation), classified as bronchopulmonary dysplasia (BPD) or non-BPD, and healthy term controls were studied. Lung function was measured by forced oscillation technique (respiratory resistance [Rrs] and reactance [Xrs]) and spirometry. Respiratory symptom questionnaires were administered.

RESULTS

One hundred and fifty children (74 BPD, 44 non-BPD, 32 controls) 4-8 years were studied. Lung function (median Z-score [10,90th centile]) was significantly impaired in preterm children compared to controls for FVC (0.00 [-1.18, 1.76], 0.69 [-0.17,1.86]), FEV₁ (-0.44 [-1.94, 1.11], 0.49 [-0.83, 2.51]), Xrs (-1.26 [-3.31, 0.11], -0.11 [-0.97, 0.73]), and Rrs (0.55 [-0.48, 1.82], 0.28 [-0.99, 0.96]). Only Xrs differed between the BPD and non-BPD (-1.51 [-3.59, -0.41], -0.89 [-2.64, 0.52]). The prevalence of recent respiratory symptoms (range: 32-36%) did not differ between BPD and non-BPD children. Supplemental O₂ in hospital was positively associated with worsening Xrs and FEV₁ .

CONCLUSION

Preterm children have worse lung function than healthy controls. Only respiratory reactance differentiated between preterm children with and without BPD and was influenced by days of O₂ in hospital. Pediatr Pulmonol. 2016;51:1347-1355. © 2016 Wiley Periodicals, Inc.

Reproducibility of serum IgE, Ara h2 skin prick testing and fraction of exhaled nitric oxide for predicting clinical peanut allergy in children

BACKGROUND

Ara h2 sIgE serum levels improve the diagnostic accuracy for predicting peanut allergy, but the use of Ara h2 purified protein as a skin prick test (SPT), has not been substantially evaluated. The fraction of exhaled nitric oxide (FeNO) shows promise as a novel biomarker of peanut allergy. Reproducibility of these measures has not been determined. The aim was to assess the accuracy and reproducibility (over a time-period of at least 12 months) of SPT to Ara h2 in comparison with four predictors of clinical peanut allergy (Peanut SPT, Ara h2 specific Immunoglobulin E (sIgE), Peanut sIgE and FeNO).

METHODS

Twenty-seven children were recruited in a follow-up of a prospective cohort of fifty-six children at least 12 months after an open-labelled peanut food challenge. Their repeat assessment involved a questionnaire, SPT to peanut and Ara h2 purified protein, FeNO and sIgE to peanut and Ara h2 measurements.

RESULTS

Ara h2 SPT was no worse in accuracy when compared with peanut SPT, FeNO, Ara h2 sIgE and peanut sIgE (AUC 0.908 compared with 0.887, 0.889, 0.935 and 0.804 respectively) for predicting allergic reaction at previous food challenge. SPT for peanut and Ara h2 demonstrated limited reproducibility (ICC = 0.51 and 0.44); while FeNO demonstrated good reproducibility (ICC = 0.73) and sIgE for peanut and Ara h2 were highly reproducible (ICC = 0.81 and 0.85).

CONCLUSIONS

In this population, Ara h2 SPT was no worse in accuracy when compared with current testing for the evaluation of clinical peanut allergy, but had-like peanut SPT-poor reproducibility. FeNO, peanut sIgE and Ara h2 sIgE were consistently reproducible despite an interval of at least 12 months between the repeated measurements.

Management of Prematurity-Associated Wheeze and Its Association with Atopy

Introduction

Although preterm birth is associated with respiratory morbidity in childhood, the role of family history of atopy and whether appropriate treatment has been instituted is unclear. Thus we assessed (i) the prevalence of respiratory symptoms, particularly wheezing, in childhood; (ii) evaluated the role of family history of atopy and mode of delivery, and (iii) documented the drug usage, all in preterm-born children compared to term-born control children.

Methods

We conducted a cross-sectional population-based questionnaire study of 1–10 year-old preterm-born children (n = 13,361) and matched term-born controls (13,361). Data (n = 7,149) was analysed by gestational groups (24–32 weeks, 33–34 weeks, 35–36 weeks and 37–43 weeks) and by age, <5 years old or ≥ 5 years.

Main Results

Preterm born children aged <5 years (n = 2,111, term n = 1,402) had higher rates of wheeze-ever [odds ratio: 2.7 (95% confidence intervals 2.2, 3.3); 1.8 (1.5, 2.2); 1.5 (1.3, 1.8) respectively for the 24–32 weeks, 33–34 weeks, 35–36 weeks groups compared to term]. Similarly for the ≥5 year age group (n = 2,083, term n = 1,456) wheezing increased with increasing prematurity [odds ratios 3.3 (2.7, 4.1), 1.8 (1.5, 2.3) and 1.6 (1.3, 1.9) for the three preterm groups compared to term]. At both age groups, inhaler usage was greater in the lowest preterm group but prematurity-associated wheeze was independent of a family history of atopy.

Conclusions

Increasing prematurity was associated with increased respiratory symptoms, which were independent of a family history of atopy. Use of bronchodilators was also increased in the preterm groups but its efficacy needs careful evaluation.

Early-term birth is a risk factor for wheezing in childhood: A cross-sectional population study

BACKGROUND

Early term-born (37-38 weeks' gestation) infants have increased respiratory morbidity during the neonatal period compared with full term-born (39-42 weeks' gestation) infants, but longer-term respiratory morbidity remains unclear.

OBJECTIVE

We assessed whether early term-born children have greater respiratory symptoms and health care use in childhood compared with full term-born children.

METHODS

We surveyed 1- to 10-year-old term-born children (n = 13,361). Questionnaires assessed respiratory outcomes with additional data gathered from national health databases.

RESULTS

Of 2,845 eligible participants, 545 were early term-born and 2,300 were full term-born. Early term-born children had higher rates of admission to the neonatal unit (odds ratio [OR], 1.7; 95% CI, 1.2-2.5) and admission to the hospital during their first year of life (OR, 1.6; 95% CI, 1.2-2.1). Forty-eight percent of early term-born children less than 5 years old reported wheeze ever compared with 39% of full term-born children (OR, 1.5; 95% CI, 1.1-1.9), and 26% versus 17% reported recent wheezing (OR, 1.7; 95% CI, 1.3-2.4). Early term-born children older than 5 years reported higher rates of wheeze ever (OR, 1.4; 95% CI, 1.05-1.8) and recent wheezing over the last 12 months than full-term control subjects (OR, 1.4; 95% CI, 1.02-2.0). Increased rates of respiratory symptoms in early term-born children persisted when family history of atopy and delivery by means of cesarean sections were included in logistic regression models.

CONCLUSION

Early term-born children had significantly increased respiratory morbidity and use of health care services when compared with full term-born children, even when stratified by mode of delivery and family history of atopy.

Validation of a questionnaire for asthma case identification in pre-schools in Latin America

BACKGROUND AND OBJECTIVE

We recently developed and validated a screening questionnaire for determining which school-aged children may need further investigation to diagnose and manage asthma. In the present study we sought to extend this to pre-school aged children.

METHODS

Questions from the school-aged questionnaire and literature on pre-school asthma were used to inform a focus group of parents with pre-school-aged children with asthma to develop a screening questionnaire. Parents of children attending 6 randomly selected kindergartens in Trelew, Argentina (n = 639) were invited to respond to the questionnaire. A reliability test-retest was undertaken in 187 randomly selected parents who completed the same questionnaire twice within 2-5 weeks. Clinical assessment included a standardized history and physical examination, spirometry before and after a β-agonist inhaler, and chest X-ray. Asthma was diagnosed by the pulmonologist.

RESULTS

Completed surveys were returned for 620 children, 607 of whom underwent clinical evaluation. The mean age was 4.21 years (range of 3.01-5.50) and included 82.5% white and 49.4% male children. Asthma was diagnosed in 103 (17.0%) children); 72 (69.9%) of these children did not have a previous diagnosis of asthma. The specificity, sensitivity, positive predictive value and negative predictive value of the questionnaire were 93.2%, 86.1%, 57.8% and 98.4%, respectively.

CONCLUSIONS

We have demonstrated the utility of a screening questionnaire for identifying pre-school-aged children who may benefit from further assessment for asthma.

Evidence that asthma is a developmental origin disease influenced by maternal diet and bacterial metabolites

Asthma is prevalent in Western countries, and recent explanations have evoked the actions of the gut microbiota. Here we show that feeding mice a high-fibre diet yields a distinctive gut microbiota, which increases the levels of the short-chain fatty acid, acetate. High-fibre or acetate-feeding led to marked suppression of allergic airways disease (AAD, a model for human asthma), by enhancing T-regulatory cell numbers and function. Acetate increases acetylation at the Foxp3 promoter, likely through HDAC9 inhibition. Epigenetic effects of fibre/acetate in adult mice led us to examine the influence of maternal intake of fibre/acetate. High-fibre/acetate feeding of pregnant mice imparts on their adult offspring an inability to develop robust AAD. High fibre/acetate suppresses expression of certain genes in the mouse fetal lung linked to both human asthma and mouse AAD. Thus, diet acting on the gut microbiota profoundly influences airway responses, and may represent an approach to prevent asthma, including during pregnancy.

An observational study examining the relationship between respiratory symptoms, airway inflammation and bacteriology in children with severe neurodisability

Background

Children with severe neurodisability (ND) commonly suffer from chronic respiratory symptoms that impact greatly on quality of life, and lead to recurrent hospital admissions. This morbidity (and its causes) is poorly described, despite being well recognised by paediatricians. In this study, we characterised respiratory symptoms in children with ND at times of stability and deterioration. We also assessed the relationship between respiratory symptoms, lower airway inflammatory markers and levels of infection/colonisation.

Methods

ND children were recruited upon admission for elective surgery (Elective-ND [n = 16]), or acutely upon admission to Intensive Care (PICU-ND [n = 19]), and compared to healthy control children [n = 12]. Parents completed a validated respiratory symptom questionnaire in which symptoms associated with activity were removed (total maximal score of 108). Bronchoalveolar lavage (BAL) was collected, and BAL neutrophil counts, IL-8 and TGFβ-1 levels measured. BAL microbial analysis was performed using a 16S/18S rRNA gene based assay and Pseudomonas aeruginosa PCR.

Results

All ND children had high levels of respiratory symptoms (median [IQR] symptom score PICU-ND, 55[38-64]; Elective-ND, 26[7-45]; Control, 4[0-7]: p<0.01), which affected their families, particularly at nighttime. Elective-ND patients with a total respiratory symptom score >20 invariably had BAL neutrophilia. Elective patients with 16S/18S microbial rDNA positive BAL had higher neutrophil counts (positive, 33[18-70]%; negative, 8[4-38]%: p<0.05) and generally higher symptom scores (positive, 17[5-32]; negative, 5[0-9]: p = 0.097). Streptococcus mitis was commonly identified in BAL from ND children; Pseudomonas aeruginosa was not identified in any sample.

Conclusions

Children with severe ND often have high levels of chronic respiratory symptoms, which may relate to lower airway inflammation. Bacterial airway colonisation, particularly with oral commensals, may play a role in both symptom generation and inflammation.

Ventilation inhomogeneities in children with congenital thoracic malformations

Background

Congenital thoracic malformations (CTM) are rare lung lesions that are managed with surgical resection or active surveillance.

The objective of this study was to comprehensively assess large and small airway function in children with CTM who underwent lobectomy in early life.

We hypothesise that sensitive measures of lung function will demonstrate residual impairments in CTM compared to healthy children.

Methods

Nitrogen lung clearance index (LCI), reactance and resistance (X5Hz and R5Hz), forced expiratory volume in 1 s and forced vital capacity (FEV1 and FVC) were prospectively measured in 10 children with CTM (mean age/SD: 7.6/1.3) who had undergone surgical resection in early life and in 17 healthy children (mean age/SD: 4.8/0.4). Total lung capacity (TLC) was also conducted in children older than 7 years of age with CTM (n = 8).

Results

Mean LCI was 8.0 (95% CI 7.5 to 8.5) in the CTM group and 7.3 (95% CI 7.0 to 7.6) in healthy children (p = 0.016). Mean X5Hz was −0.44kPa/l/s (95% CI −0.58 to −0.31) in the CTM group and −0.31kPa/l/s (95% CI −0.35 to −0.27) in healthy children (p = 0.02). Mean Z score for X5Hz was −2.11 (95% CI −3.59 to −0.63) in the CTM group and −0.11 (95% CI −0.55 to 0.33) in healthy children (p = 0.0008). Mean FEV1 was 1.21 L (95% CI 0.97 to 1.45) in the CTM group and 1.02 L (95% CI 0.90 to 1.15) in healthy children (p = 0.22). Mean % predicted FEV1 was 83% (95% CI 74 to 92) in the CTM group and 97% (95% CI 87 to 107) in healthy children (p < 0.05). Mean % predicted TLC in CTM children was 121.3% (95% CI 88.45 to 154.1). Mean LCI was inversely correlated with height z-scores in the CTM group (rs = −0.88, p = 0.002) but not in healthy children (rs = 0.22, p = 0.4).

Conclusions

Children with CTM have impaired lung function as demonstrated by the significant differences in LCI, reactance and FEV1 but not FVC, resistance and TLC. These findings may be of clinical relevance as ventilation inhomogeneities are closely correlated with somatic growth in this study.

Electronic supplementary material

The online version of this article (doi:10.1186/s12890-015-0023-1) contains supplementary material, which is available to authorized users.

Exhaled biomarkers and gene expression at preschool age improve asthma prediction at 6 years of age

RATIONALE

A reliable asthma diagnosis is difficult in wheezing preschool children.

OBJECTIVES

To assess whether exhaled biomarkers, expression of inflammation genes, and early lung function measurements can improve a reliable asthma prediction in preschool wheezing children.

METHODS

Two hundred two preschool recurrent wheezers (aged 2-4 yr) were prospectively followed up until 6 years of age. At 6 years of age, a diagnosis (asthma or transient wheeze) was based on symptoms, lung function, and asthma medication use. The added predictive value (area under the receiver operating characteristic curve [AUC]) of biomarkers to clinical information (assessed with the Asthma Predictive Index [API]) assessed at preschool age in diagnosing asthma at 6 years of age was determined with a validation set. Biomarkers in exhaled breath condensate, exhaled volatile organic compounds (VOCs), gene expression, and airway resistance were measured.

MEASUREMENTS AND MAIN RESULTS

At 6 years of age, 198 children were diagnosed (76 with asthma, 122 with transient wheeze). Information on exhaled VOCs significantly improved asthma prediction (AUC, 89% [increase of 28%]; positive predictive value [PPV]/negative predictive value [NPV], 82/83%), which persisted in the validation set. Information on gene expression of toll-like receptor 4, catalase, and tumor necrosis factor-α significantly improved asthma prediction (AUC, 75% [increase of 17%]; PPV/NPV, 76/73%). This could not be confirmed after validation. Biomarkers in exhaled breath condensate and airway resistance (pre- and post- bronchodilator) did not improve an asthma prediction. The combined model with VOCs, gene expression, and API had an AUC of 95% (PPV/NPV, 90/89%).

CONCLUSIONS

Adding information on exhaled VOCs and possibly expression of inflammation genes to the API significantly improves an accurate asthma diagnosis in preschool children. Clinical trial registered with www.clinicaltrial.gov (NCT 00422747).

Differential DNA methylation profiles of infants exposed to maternal asthma during pregnancy

BACKGROUND

Asthma is a complex disease that involves both genetic factors and environmental exposures. Aberrant epigenetic modifications, such as DNA methylation, may be important in asthma development. Fetal exposure to maternal asthma during critical periods of in utero development may lead to epigenetic alterations that predispose infants to a greater risk of developing asthma themselves. We investigated alterations in the DNA methylation profile of peripheral blood from infants exposed to maternal asthma during pregnancy.

METHODS

Peripheral blood was collected from 12-month-old infants born to women with (n = 25) and without (n = 15) doctor diagnosed asthma during pregnancy. Genomic DNA was extracted, bisulfite converted, and hybridized to Infinium Methylation 27 arrays (Illumina), containing over27,000 CpGs from 14,495 genes. CpG loci in only autosomal genes were classified as differentially methylated at the 99% level (P < 0.01, |DiffScore| > 22 and delta beta >0.06).

RESULTS

There were 70 CpG loci, corresponding to 67 genes that were significantly differentially methylated. Twelve CpG loci (11 genes) showed greater than 10% comparative difference in DNA methylation, including hyper-methylated loci of FAM181A, MRI1, PIWIL1, CHFR, DEFA1, MRPL28, AURKA, and hypo-methylated loci of NALP1L5, MAP8KIP3, ACAT2, and PM20D1 in maternal asthma. Methylation of MAPK8IP3 was significantly negatively correlated with maternal blood eosinophils (r = -0.38; P = 0.022), maternal eNO (r = -0.44; P = 0.005), and maternal serum total IgE (r = -0.39, P = 0.015). Methylation of AURKA negatively correlated with maternal hemoglobin (r = -0.43; P = 0.008), infants height (r = -0.51; P < 0.001) and weight (r = -0.36; P = 0.021). Methylation of PM20D1 was lower in infants born to mothers with asthma on inhaled corticosteroid treatment. Methylation of PM20D1 was lower and MRI1 was higher in infants born to atopic mothers without asthma.

CONCLUSIONS

In an Australian study population, exposure to maternal asthma during pregnancy is associated with differential methylation profiles of infants' peripheral blood DNA, which may act as risk factors for future asthma development.

Amnioinfusion in very early preterm prelabor rupture of membranes (AMIPROM): pregnancy, neonatal and maternal outcomes in a randomized controlled pilot study

OBJECTIVE

To assess short- and long-term outcomes of pregnant women with very early rupture of membranes randomized to serial amnioinfusion or expectant management, and to collect data to inform a larger, more definitive clinical trial.

METHODS

This was a prospective non-blinded randomized controlled trial with randomization stratified for pregnancies in which the membranes ruptured between 16 + 0 and 19 + 6 weeks' gestation and 20 + 0 and 23 + 6 weeks' gestation to minimize the risk of random imbalance in gestational age distribution between randomized groups. Intention-to-treat analysis was used. The study was conducted in four UK hospital-based fetal medicine units (Liverpool Women's NHS Trust, St Mary's Hospital Manchester, Birmingham Women's NHS Foundation Trust and Wirral University Hospitals Trust). The participants were women with confirmed preterm prelabor rupture of membranes at 16 + 0 to 24 + 0 weeks' gestation. Women with multiple pregnancy, fetal abnormality or obstetric indication for immediate delivery were excluded. Participants were randomly allocated to either serial weekly transabdominal amnioinfusions if the deepest pool of amniotic fluid was < 2 cm or expectant management until 37 weeks' gestation. Short-term maternal, pregnancy and neonatal and long-term outcomes for the child were studied. Long-term respiratory morbidity was assessed using validated respiratory questionnaires at 6, 12 and 18 months of age and infant lung function test at around 12 months of age. Neurodevelopment was assessed using the Bayley Scales of Infant Development, second edition (BSID-II) at corrected age of 2 years.

RESULTS

Fifty-eight women were randomized to the study. Two babies were excluded from the analysis because of termination of pregnancy for lethal anomaly, leaving 56 participants (28 assigned to serial amnioinfusion and 28 to expectant management) recruited between 2002 and 2009. There was no significant difference in perinatal mortality (19/28 vs 19/28; relative risk (RR) 1.0 (95% CI, 0.70-1.43)) and maternal or neonatal morbidity. The overall chance of surviving without long-term respiratory or neurodevelopmental disability was 4/56 (7.1%); 4/28 (14.3%) in the amnioinfusion group and 0/28 in the expectant group (RR 9.0 (95% CI, 0.51-159.70)).

CONCLUSIONS

This pilot study found no major differences in maternal, perinatal or pregnancy outcomes. The study was not designed to show a difference between the groups and the number of survivors was too small to draw any conclusions about long-term outcomes. It does, however, signal that a larger definitive study to evaluate amnioinfusion for improvement in healthy survival is needed. The pilot suggests that, with appropriate funding, such a study is feasible.

Prenatal origins of bronchiolitis: protective effect of optimised asthma management during pregnancy

Objective

Maternal asthma is the most common chronic disease complicating pregnancy and is a risk factor for bronchiolitis in infancy. Recurrent episodes of bronchiolitis are strongly associated with the development of childhood asthma.

Methods

We conducted a follow-up study of infants born to women with asthma who completed a double-blind randomised controlled trial during pregnancy. In this trial, pregnant women with asthma were assigned to treatment adjustment by an algorithm using clinical symptoms (clinical group) or the fraction of exhaled nitric oxide (FeNO group) and we showed that the FeNO group had significantly lower asthma exacerbation rates in pregnancy.

Results

146 infants attended the 12-month follow-up visit. Infants born to mothers from the FeNO group were significantly less likely to have recurrent episodes of bronchiolitis in the first year of life (OR 0.08, 95% CI 0.01 to 0.62; p=0.016) as compared with the clinical group.

Conclusions

Optimised management of asthma during pregnancy may reduce recurrent episodes of bronchiolitis in infancy, which could potentially modulate the risk to develop or the severity of emerging childhood asthma.

Protease concentration in amniotic fluid at term and early childhood respiratory symptoms

OBJECTIVE

Asthma is a common chronic disease associated with altered proteolytic activity. The present study tested the hypothesis that altered protease concentration in amniotic fluid (AF), an index of airway fluid at birth, precedes early cough and wheeze.

METHODS

AF was collected and analysed for the following: matrix metalloproteinases (MMP) -2, -8 and -9, tissue inhibitor of metalloproteinases (TIMP) -1 and 2, plasminogen activator inhibitor (PAI)-1. Infant were followed up at ages 1, 2 and 3 years.

RESULTS

Samples of AF were obtained in 92 infants. There were inconsistent and relatively small differences in some analytes between those individuals with and without symptoms at ages one and two years. PAI-1 concentrations were reduced in association with cough at age 1 year (p = 0.035). Reduced MMP-8:TIMP-2 ratio was associated with wheeze at age 2 years (p = 0.038). There were no associations between AF analytes and symptoms at 3 years of age.

CONCLUSION

There is heterogeneity in concentrations of proteases and their inhibitors in airways at birth but in this exploratory study, there was no consistent evidence that protease concentration at birth was important to later respiratory symptoms.

A motivational interviewing intervention to PREvent PAssive Smoke Exposure (PREPASE) in children with a high risk of asthma: design of a randomised controlled trial

Background

Especially children at risk for asthma are sensitive to the detrimental health effects of passive smoke (PS) exposure, like respiratory complaints and allergic sensitisation. Therefore, effective prevention of PS exposure in this group of vulnerable children is important. Based on previous studies, we hypothesized that an effective intervention program to prevent PS exposure in children is possible by means of a motivational interviewing tailored program with repeated contacts focussing on awareness, knowledge, beliefs (pros/cons), perceived barriers and needs of parents, in combination with feedback about urine cotinine levels of the children. The aim of the PREPASE study is to test the effectiveness of such an intervention program towards eliminating or reducing of PS exposure in children at risk for asthma. This article describes the protocol of the PREPASE study.

Methods

The study is a one-year follow-up randomized controlled trial. Families with children (0–13 years of age) having an asthma predisposition who experience PS exposure at home are randomized into an intervention group receiving an intervention or a control group receiving care as usual. The intervention is given by trained research assistants. The intervention starts one month after a baseline measurement and takes place once per month for an hour during six home based counselling sessions. The primary outcome measure is the percentage of families curtailing PS exposure in children (parental report verified with the urine cotinine concentrations of the children) after 6 months. The secondary outcome measures include: household nicotine level, the child’s lung function, airway inflammation and oxidative stress, presence of wheezing and questionnaires on respiratory symptoms, and quality of life. A process evaluation is included. Most of the measurements take place every 3 months (baseline and after 3, 6, 9 and 12 months of study).

Conclusion

The PREPASE study incorporates successful elements of previous interventions and may therefore be very promising. If proven effective, the intervention will benefit the health of children at risk for asthma and may also create opportunity to be tested in other population.

Trial registration number

NTR2632

Symptoms, but not a biomarker response to inhaled corticosteroids, predict asthma in preschool children with recurrent wheeze

Background. A reliable asthma diagnosis is challenging in preschool wheezing children. As inhaled corticosteroids (ICS) are more effective in asthmatics than in children with transient wheeze, an ICS response might be helpful in early asthma diagnosis. Methods. 175 children (aged two–four years) with recurrent wheeze received 200 μg Beclomethasone extra-fine daily for eight weeks. Changes in Exhaled Breath Condensate (EBC) biomarkers (pH, interleukin (IL)-1α, IL-2, IL-4, IL-5, IL-10, IFN-γ, sICAM, and CCL-11), Fractional exhaled Nitric Oxide (FeNO), airway resistance, and symptoms were assessed. At six years of age a child was diagnosed as transient wheezer or asthmatic. Adjusted logistic regression analysis was performed with multiple testing correction. Results. 106 transient wheezers and 64 asthmatics were analysed at six years of age. Neither changes in EBC biomarkers, nor FeNO, airway resistance, or symptoms during ICS trial at preschool age were related to asthma diagnosis at six years of age. However, asthmatics had more airway symptoms before the start of the ICS trial than transient wheezers (P < 0.01). Discussion. Although symptom score in preschool wheezing children at baseline was associated with asthma at six years of age, EBC biomarkers, airway resistance, or symptom response to ICS at preschool age could not predict asthma diagnosis at six years of age.

Reflux aspiration in children with neurodisability--a significant problem, but can we measure it?

Recurrent respiratory problems are common in children with severe neurodisability, and respiratory deterioration is a leading cause of premature death in this group. Although the etiology is multifactorial, recurrent pulmonary aspiration is thought to play a significant role. Gastroesophageal reflux is known to be common, as is oral-motor discoordination. Differentiating direct aspiration of food and saliva and gastric reflux aspiration is difficult and presents a challenge in managing patients and assessing their suitability for surgical antireflux procedures. This is particularly the case when children present with predominantly respiratory symptoms, where there may be direct aspiration, reflux aspiration, neither, or both. A clinical biomarker to identify and quantify reflux aspiration would therefore be useful in surgical assessment and may also be applicable as an outcome measure for clinical trials of antireflux surgery. In this review, we discuss the evidence base behind existing and potentially novel biomarkers of aspiration in bronchoalveolar lavage fluid. We highlight the limitations of the lipid-laden macrophage index, particularly with regard to its specificity and interrater/intrarater reliability. We discuss the laboratory methods available to measure promising new biomarkers (pepsin and bile acids) and highlight their potential advantages and disadvantages. Finally, to understand how aspiration causes clinical signs and symptoms in our patients, we need to study the effect of aspirated substances on the lung, and here we review the available in vivo and in vitro literature.

Can exhaled inflammatory markers predict a steroid response in wheezing preschool children?

BACKGROUND

The efficacy of inhaled corticosteroids (ICS) varies among wheezing preschool children. Currently, it is not possible to predict which fraction of wheezing children will benefit from an ICS treatment.

OBJECTIVE

We explored whether fractional exhaled nitric oxide (FeNO) and inflammatory markers in exhaled breath condensate (EBC) can predict an ICS response in preschool wheezers.

METHODS

An 8-week ICS study (registered at Clinicaltrial.gov: NCT 00422747; 200 μg; beclomethasone extra-fine daily) was performed in 93 wheezing children (age range 2.0-4.4 years). At baseline, FeNO was determined off-line. EBC was collected using a closed glass-condenser. The acidity of EBC was determined and other EBC markers [interleukin (IL)-1α, IL-2, IL-4, IL-5, IL-10, soluble intercellular adhesion molecule, interferon-γ, eotaxin] were measured using a multiplex immunoassay. The change in airway resistance (Rint) and symptom score following ICS treatment was related to atopy (positive Phadiatop Infant test), FeNO and EBC markers.

RESULTS

Airway resistance and symptoms mildly improved after ICS treatment [median (IQR): 1.4 (1.2-1.7) to 1.3 (1.1-1.5) kPa s/L, symptom score: 26 (23-28) to 28 (24-29), P < 0.01, respectively]. Only IL-10 and atopy had limited predictive value regarding a change in symptoms [β (SE) =-0.13 (0.07), P = 0.08, β (SE) = 2.05 (1.17), P = 0.08, respectively].

CONCLUSIONS AND CLINICAL RELEVANCE

We did not find convincing evidence that FeNO and EBC markers could predict an ICS response in preschool wheezers. Recommendations for future studies on this topic are given.

A primary health-care intervention on pre- and postnatal risk factor behavior to prevent childhood allergy. The Prevention of Allergy among Children in Trondheim (PACT) study

Background

This study aimed to evaluate the impact of a primary prevention intervention program on risk behavior for allergic diseases among children up to 2 years of age. The setting was in ordinary pre- and postnatal primary health care in Trondheim, Norway.

Methods

The Prevention of Allergy among Children in Trondheim, Norway (PACT) study invited all pregnant women and parents to children up to 2 years of age in the community to participate in a non-randomized, controlled, multiple life-style intervention study. Interventional topics was increased dietary intake of cod liver oil and oily fish for women during pregnancy and for infants during the first 2 years of life, reduced parental smoking and reduced indoor dampness. A control cohort was established prior to the intervention cohort with "follow up as usual". Questionnaires were completed in pregnancy, 6 weeks after birth and at 1 and 2 years of age. Trends in exposure and behavior are described.

Results

Intake of oily fish and cod liver oil increased statistically significantly among women and infants in the intervention cohort compared to the control cohort. There was a low postnatal smoking prevalence in both cohorts, with a trend towards a decreasing smoking prevalence in the control cohort. There was no change in indoor dampness or in behavior related to non- intervened life-style factors.

Conclusions

The dietary intervention seemed to be successful. The observed reduced smoking behavior could not be attributed to the intervention program, and the latter had no effect on indoor dampness.

Trial registrations

(Current Controlled Trials registration number: ISRCTN28090297)

Validation of a Pediatric Cough Questionnaire

We conducted a study to determine if a five-item pediatric cough questionnaire (PCQ) is a valid and reliable means of measuring cough-specific quality of life in children. The five questions, which are answered by the child's parent or caregiver, cover cough frequency (Q1), sleep disturbance of the child (Q2), sleep disturbance of the parent (Q3), cough severity (Q4), and the degree of bothersomeness to the child (Q5). Each of the five items was scored on a 6-point Likert scale. The PCQ was administered three times. The first occurred when the parent telephoned to schedule an appointment for the child at a pediatric pulmonology outpatient clinic for a chief complaint of cough. The second PCQ was administered within 2 weeks of the first but before any treatment had been instituted so that test-retest reliability could be assessed. Each child was then diagnosed and treated in accordance with standard care practices. The third PCQ was administered 3 weeks after the second to determine if it would accurately reflect the parent's perception of how the child's cough had changed following treatment. Also, at the second and third encounters, parents were asked to provide their global assessment of whether their child's cough had improved, worsened, or stayed the same since the previous encounter. The parents of 120 children (70 boys and 50 girls; mean age: 6.8 yr) completed all three PCQs. Test-retest reliability was established (p < 0.001) for each of the five PCQ questions by Spearman correlation analysis (Q1: r = 0.5; Q2: r = 0.38; Q3: r = 0.42; Q4: r = 0.53; Q5: r = 0.5). Other statistical analyses confirmed the PCQ's internal consistency, discriminant validity, and convergent validity. Based on our findings, we conclude that the PCQ is a valid and reliable instrument with which to follow children with chronic cough longitudinally.

Identifying preschool children with asthma in Orange County

Airway changes related to childhood asthma occur early in the disease process. This pilot study focuses on the validation of the Breathmobile Case Identification Survey (BCIS) in preschool-age children in Orange County, CA. Fifty-two children from low-income Spanish-speaking families participated in the study. Thirteen children were identified as possibly having asthma from the survey results compared with 20 children diagnosed by an asthma specialist. We found that the complete seven-question survey had a sensitivity of 0.65 and a specificity of 0.94. An abbreviated three-question version had a sensitivity of 0.70 and a specificity of 0.84. Our data suggest that the abbreviated BCIS, which is simple and easily analyzed, may be a useful tool in identifying young children who are at risk for asthma and need further evaluation and appropriate therapy.

Early diagnosis of asthma in young children by using non-invasive biomarkers of airway inflammation and early lung function measurements: study protocol of a case-control study

Background

Asthma is the most common chronic disease in childhood, characterized by chronic airway inflammation. There are problems with the diagnosis of asthma in young children since the majority of the children with recurrent asthma-like symptoms is symptom free at 6 years, and does not have asthma. With the conventional diagnostic tools it is not possible to differentiate between preschool children with transient symptoms and children with asthma. The analysis of biomarkers of airway inflammation in exhaled breath is a non-invasive and promising technique to diagnose asthma and monitor inflammation in young children. Moreover, relatively new lung function tests (airway resistance using the interrupter technique) have become available for young children. The primary objective of the ADEM study (Asthma DEtection and Monitoring study), is to develop a non-invasive instrument for an early asthma diagnosis in young children, using exhaled inflammatory markers and early lung function measurements. In addition, aetiological factors, including gene polymorphisms and gene expression profiles, in relation to the development of asthma are studied.

Methods/design

A prospective case-control study is started in 200 children with recurrent respiratory symptoms and 50 control subjects without respiratory symptoms. At 6 years, a definite diagnosis of asthma is made (primary outcome measure) on basis of lung function assessments and current respiratory symptoms ('golden standard'). From inclusion until the definite asthma diagnosis, repeated measurements of lung function tests and inflammatory markers in exhaled breath (condensate), blood and faeces are performed. The study is registered and ethically approved.

Discussion

This article describes the study protocol of the ADEM study. The new diagnostic techniques applied in this study could make an early diagnosis of asthma possible. An early and reliable asthma diagnosis at 2–3 years will have consequences for the management of the large group of young children with asthma-like symptoms. It will avoid both over-treatment of children with transient wheeze and under-treatment of children with asthma. This might have a beneficial influence on the prognosis of asthma in these young children. Besides, insight into the pathophysiology and aetiology of asthma will be obtained.

TRIAL REGISTRATION

This study is registered by clinicaltrials.gov (NCT00422747).

Environmental tobacco smoke and interleukin 4 polymorphism (C-589T) gene: environment interaction increases risk of wheezing in African-American infants

OBJECTIVES

To determine whether infants exposed to environmental tobacco smoke (ETS) having the interleukin 4 (IL-4) or interleukin 13 (IL-13) gene polymorphisms were at increased risk of wheezing.

STUDY DESIGN

A birth cohort of 758 infants was evaluated annually by a questionnaire, physical examination, and skin prick testing. DNA samples from 560 children were genotyped for IL-4 C-589T and IL-13 C-1112T. The relationship of ETS exposure and genotype with the outcome of wheezing was analyzed.

RESULTS

At the time of evaluation, mean age was 13.4 +/- 2.2 months. The prevalence of sensitization was 29%, and wheezing without a cold was 26.2%. The interaction of ETS exposure and the CT/TT genotypes for IL-4 C-589T showed a significant association with wheezing (odds ratio: 10.84; 95% confidence interval: 1.12-104.64, P = .04) in African-American infants.

CONCLUSIONS

In African-American infants with a family history of atopy, the interaction of ETS and IL-4 C-589T demonstrated a 10-fold risk associated with wheezing without a cold.

Lung function measurement in prematurely born preschool children with and without chronic lung disease

OBJECTIVE

Prematurely born infants often have recurrent wheeze and long-term respiratory morbidity at follow-up. Assessment of airways obstruction in preschool children is feasible using the interrupter resistance (Rint) but has rarely been examined in preterm children with and without chronic lung disease (CLD). The objective of this study was to determine lung function measured by the interrupter technique, its feasibility in the ambulatory setting and respiratory health in prematurely born preschool children with and without CLD.

STUDY DESIGN

Preterm children of 2 to 4 years with severe CLD (>30% oxygen at 36 weeks and discharged home receiving supplemental oxygen) (n=43, median gestational age 27 weeks and median birth weight 995 g) and without CLD (n=33, median gestational age 29 weeks and median birth weight 1366 g) attempting lung function test for the first time were enrolled. Respiratory symptoms score was calculated using a questionnaire. A single set of 10 consecutive Rint measurements was obtained using a portable device (MicroRint). Median of at least five occlusions with consistent shape of mouth pressure-time curves was taken to be a Rint measurement. To assess feasibility the children were categorized as 'satisfactory', 'failure' and 'rejected' depending on the outcome of the test. Outcome variables were respiratory symptoms score and Rint.

RESULT

Satisfactory Rint measurement was obtained in 46 (61%) children, 9 (36%) 2-year olds, 17 (65%) 3-year olds and 20 (80%) 4-year olds. As compared with the preterm control children (n=18), CLD children (n=28) had significantly higher respiratory symptoms score (18.5 vs 6, P<0.01) and Rint expressed as absolute values (kPa l(-1)) and z-scores (1.33 vs 1.16 and 1.42 vs 1.0, P<0.01), respectively.

CONCLUSION

Rint measurement is feasible in prematurely born children of preschool age in the ambulatory setup. Preschool children with severe CLD may be identified from preterm children without CLD by increased Rint that may be used as a screening tool and as an outcome measure for interventions.

Factor analysis in the Genetics of Asthma International Network family study identifies five major quantitative asthma phenotypes

BACKGROUND

Asthma is a clinically heterogeneous disease caused by a complex interaction between genetic susceptibility and diverse environmental factors. In common with other complex diseases the lack of a standardized scheme to evaluate the phenotypic variability poses challenges in identifying the contribution of genes and environments to disease expression.

OBJECTIVE

To determine the minimum number of sets of features required to characterize subjects with asthma which will be useful in identifying important genetic and environmental contributors. Methods Probands aged 7-35 years with physician diagnosed asthma and symptomatic siblings were identified in 1022 nuclear families from 11 centres in six countries forming the Genetics of Asthma International Network. Factor analysis was used to identify distinct phenotypes from questionnaire, clinical, and laboratory data, including baseline pulmonary function, allergen skin prick test (SPT).

RESULTS

Five distinct factors were identified:(1) baseline pulmonary function measures [forced expiratory volume in 1 s (FEV(1)) and forced vital capacity (FVC)], (2) specific allergen sensitization by SPT, (3) self-reported allergies, (4) symptoms characteristic of rhinitis and (5) symptoms characteristic of asthma. Replication in symptomatic siblings was consistent with shared genetic and/or environmental effects, and was robust across age groups, gender, and centres. Cronbach's alpha ranged from 0.719 to 0.983 suggesting acceptable internal scale consistencies. Derived scales were correlated with serum IgE, methacholine PC(20), age and asthma severity (interrupted sleep). IgE correlated with all three atopy-related factors, the strongest with the SPT factor whereas severity only correlated with baseline lung function, and with symptoms characteristic of rhinitis and of asthma.

CONCLUSION

In children and adolescents with established asthma, five distinct sets of correlated patient characteristics appear to represent important aspects of the disease. Factor scores as quantitative traits may be better phenotypes in epidemiological and genetic analyses than those categories derived from the presence or absence of combinations of +ve SPTs and/or elevated IgE.

A parent-completed respiratory questionnaire for 1-year-old children: repeatability

BACKGROUND AND AIMS

There are few standardised questionnaires for the assessment of respiratory symptoms in preschool children. We have developed and tested the short-term repeatability of a postal questionnaire on respiratory symptoms for 1-year-old children.

METHODS

A newly developed postal questionnaire for the assessment of wheeze and other respiratory symptoms was sent to parents of a population-based random sample of 4300 children aged 12-24 months. After an interval of 3 months, a random sample of 800 respondents received the questionnaire a second time. The responses were compared using Cohen's kappa (kappa) to assess agreement corrected for chance.

RESULTS

The first questionnaire was returned by 3194 (74%) families, the second one by 460/800 (58%). Repeatability was excellent (kappa 0.80-0.96) for questions on household characteristics, environmental exposures and family history, good (kappa 0.61-0.80) for questions on prevalence, severity and treatment of wheeze, and moderate (kappa 0.39-0.66) for chronic cough and upper respiratory symptoms.

CONCLUSIONS

This short postal questionnaire designed for use in population-based studies has excellent repeatability for family and household characteristics and good repeatability for questions on wheeze. Short-term changes in symptom status might be responsible for variable answers on recent chronic cough and upper respiratory symptoms. Overall, the questionnaire is a valuable instrument for community-based research on respiratory symptoms in 1 to 2-year-old children.

The International Study of Wheezing in Infants: questionnaire validation

BACKGROUND

There are no internationally validated questionnaires to investigate the prevalence of infant wheezing. This study was undertaken to validate a questionnaire for the International Study on the Prevalence of Wheezing in Infants (Estudio Internacional de Sibilancias en Lactantes, EISL).

MATERIAL AND METHODS

Construct and criterion validity were tested for the question 'Has your baby had wheezing or whistling in the chest during his/her first 12 months of life?'. Construct validity (i.e. the ability of parents and doctors to refer to the same symptoms with the same words) was tested in a sample of 50 wheezing and 50 non-wheezy infants 12-15 months of age in each of 10 centres from 6 different Spanish- or Portuguese-speaking countries. Criterion validity (i.e. the ability of parents to correctly detect the symptom in the general population) was evaluated in 2 samples (Santiago, Chile and Cartagena, Spain) of 50 wheezing and 50 non-wheezing infants (according to parents) of the same age, randomly selected from the general population, who were later blindly diagnosed by a paediatric pulmonologist.

RESULTS

Construct validity was very high (kappa test: 0.98-1) in all centres. According to Youden's index, criterion validity was good both in Cartagena (75.5%) and in Santiago (67.0%). Adding questions about asthma medication did not improve diagnosis accuracy.

CONCLUSIONS

The EISL questionnaire significantly distinguished wheezy infants from healthy ones. This questionnaire has a strong validity and can be employed in large international multicentre studies on wheezing during infancy.

Phenotype of acute respiratory syncytial virus induced lower respiratory tract illness in infancy and subsequent morbidity

The objective of this study was to investigate the association hypothesis that outcome following respiratory syncytial virus (RSV) induced bronchiolitis (RSVB) and RSV induced wheeze (RSVW) are different. At 3 years respiratory symptoms were more common in those with RSV infection than the control group but there was no increase in allergic sensitisation (11% vs 10%). Those with RSVW were more likely to have evidence of allergic sensitisation when compared with RSVB subjects (22% vs 7%), and have increased symptoms and increased use of inhaled steroids.

CONCLUSION

The data argue that RSV infection during infancy does not induce allergic asthma and that host factors rather than the virus determine long-term outcomes.