Development of reference equations for spirometry in Japanese children aged 6-18 years

Practical guide for the diagnosis and management of primary ciliary dyskinesia

OBJECTIVE

Primary ciliary dyskinesia (PCD) is a relatively rare genetic disorder that affects approximately 1 in 20,000 people. Approximately 50 genes are currently known to cause PCD. In light of differences in causative genes and the medical system in Japan compared with other countries, a practical guide was needed for the diagnosis and management of Japanese PCD patients.

METHODS

An ad hoc academic committee was organized under the Japanese Rhinologic Society to produce a practical guide, with participation by committee members from several academic societies in Japan. The practical guide including diagnostic criteria for PCD was approved by the Japanese Rhinologic Society, Japanese Society of Otolaryngology-Head and Neck Surgery, Japanese Respiratory Society, and Japanese Society of Pediatric Pulmonology.

RESULTS

The diagnostic criteria for PCD consist of six clinical features, six laboratory findings, differential diagnosis, and genetic testing. The diagnosis of PCD is categorized as definite, probable, or possible PCD based on a combination of the four items above. Diagnosis of definite PCD requires exclusion of cystic fibrosis and primary immunodeficiency, at least one of the six clinical features, and a positive result for at least one of the following: (1) Class 1 defect on electron microscopy of cilia, (2) pathogenic or likely pathogenic variants in a PCD-related gene, or (3) impairment of ciliary motility that can be repaired by correcting the causative gene variants in iPS cells established from the patient's peripheral blood cells.

CONCLUSION

This practical guide provides clinicians with useful information for the diagnosis and management of PCD in Japan.

Longitudinal data of serum creatine kinase levels and motor, pulmonary, and cardiac functions in 337 patients with Duchenne muscular dystrophy

INTRODUCTION/AIMS

Duchenne muscular dystrophy (DMD) presents with skeletal muscle weakness, followed by cardiorespiratory involvement. The need for longitudinal data regarding DMD that could serve as a control for determining treatment efficacy in clinical trials has increased notably. The present study examined the longitudinal data of Japanese DMD patients collectively and assessed individual patients with pathogenic variants eligible for exon-skipping therapy.

METHODS

Patients with DMD who visited Kobe University Hospital between March 1991 and March 2019 were enrolled. Data between the patients' first visit until age 20 years were examined.

RESULTS

Three hundred thirty-seven patients were included. Serum creatine kinase levels showed extremely high values until the age of 6 years and a rapid decline from ages 7-12 years. Both the median 10-m run/walk velocity and rise-from-floor velocity peaked at the age of 4 years and declined with age. The values for respiratory function declined from the age of 11 years. The median left ventricular ejection fraction was >60% until the age of 12 years and rapidly declined from ages 13-15 years. Examination of the relationship between pathogenic variants eligible for exon-skipping therapy and longitudinal data revealed no characteristic findings.

DISCUSSION

We found that creatine kinase levels and motor, respiratory, and cardiac functions each exhibited various changes over time. These findings provide useful information about the longitudinal data of several outcome measures for patients with DMD not receiving corticosteroids. These data may serve as historical controls in comparing the natural history of DMD patients not on regular steroid use in appropriate clinical trials.

Neonatal respiratory support related to lung function abnormalities in school-age children with bronchopulmonary dysplasia

OBJECTIVE

To elucidate the relationship between abnormal lung function (LF) at school age and neonatal respiratory support in very low birth weight children with bronchopulmonary dysplasia (BPD).

STUDY DESIGN

We retrospectively examined 78 BPD children whose LF was evaluated at 8-9 years. LF abnormalities were defined by reduced values of spirometric parameters. Adjusted odds ratios (aORs) for abnormal LF by the type and postmenstrual age (PMA) of respiratory support were calculated using logistic regression analysis after controlling perinatal factors.

RESULTS

Overall, 24 (31%) patients had LF abnormalities. Antenatal steroid use was associated with a decreased risk of abnormal LF [aOR, 0.31; 95% CI, 0.09-0.92]. Requiring positive-pressure support at 37 weeks' PMA correlated with abnormal LF [aOR, 4.58; 95% CI, 1.15-21.90]; whereas only low-flow oxygen at any PMA did not.

CONCLUSION

Requiring positive-pressure support at 37 weeks' PMA could be an indicator of abnormal LF at school age.

Intrauterine Ureaplasma is associated with small airway obstruction in extremely preterm infants

BACKGROUND

The long-term follow-up of lung function (LF) in extremely preterm (EP) infants with bronchopulmonary dysplasia (BPD) has shown a worldwide increase in small airway obstructions (SAO).

OBJECTIVES

We investigated the relationships between intrauterine Ureplasma infection in EP infants and bubbly/cystic lung, BPD, and SAO at school age.

METHODS

Placental pathology, placental Ureaplasma DNA (pU-DNA), and cord blood immunoglobulin M (IgM) (C-IgM) were investigated in 360 EP infants born from 1981 to 2004. Maternal amniotic inflammatory response (M-AIR) scores and hemosiderin deposition (HD) were estimated in the chorioamnion. The study subjects were divided into groups based on their M-AIR scores. Their LF at school age was compared with those of 33 healthy siblings.

FINDINGS

pU-DNA and C-IgM were significantly related to SAO at school age (p < 0.012). M-AIR score 3 and pU-DNA >1000 units had an odds ratio (OR) of 35 (95% confidence interval: 10-172) and 18 (5.6-67) for bubbly/cystic lung, and 11 (3.1 - 43) and 31 (4.5-349) for severe BPD, and 5.3 (2.1-11) and 12 (2.4-74) for SAO, respectively. The ORs of surfactant treatment, BPD grade III, O₂ at 40 weeks, HD, and C-IgM >30 mg/dl for SAO were 0.21 (0.075-0.58), 5.3 (2.1-15), 2.5 (1.4-4.6), 3.6 (1.5-9.1) and 2.5 (1.0-5.2). 84% (90/107) SAO infants showed no or mild BPD in infancy, and 61% of infants had no severe CAM.

CONCLUSION

Our long-term cohort study of LF in EP infants revealed that intrauterine Ureaplasma was associated with bubbly/cystic lung, severe BPD, and SAO at school age.

Risk Factors for Lung Function Decline in Pediatric Asthma under Treatment: A Retrospective, Multicenter, Observational Study

Background: Childhood asthma is a major risk for low lung function in later adulthood, but what factors in asthma are associated with the poor lung function during childhood is not known. Objective: To identify clinical factors in children with asthma associated with low or declining lung function during the treatment. Methods: We enrolled children with asthma who had been treated throughout three age periods, i.e., 6−9, 10−12, and 13−15 years old, at seven specialized hospitals in Japan. Clinical information and lung function measurements were retrieved from the electronic chart systems. To characterize the lung function trajectories during each age period, we evaluated the forced expiratory volume 1 (FEV1) with % predicted values and individual changes by the slope (S) from linear regression. We defined four trajectory patterns: normal (Group N) and low (Group L), showing %FEV1 ≥80% or <80% throughout all three periods; upward (Group U) and downward (Group D), showing S ≥ 0 or S < 0%. Logistic regression analysis was performed to compare factors associated with the unfavorable (D/L) versus favorable (N/U) groups. Results: Among 273 eligible patients, 197 (72%) were classified into Group N (n = 150)/U (n = 47), while 76 (28%) were in Group D (n = 66)/L (n = 10). A history of poor asthma control, long-acting beta2 agonist use, and a lower height Z-score during 13−15 years were associated with an unfavorable outcome (Group D/L). Conversely, inhaled corticosteroid (ICS) use during 10−12 years and high-dose ICS use during 13−15 years were associated with a favorable outcome (Group N/U). Conclusion: We identified several factors that are associated with unfavorable lung function changes in pediatric asthma. Attention should be paid to the possible relationship between yearly changes in lung function and poor asthma control, use of ICS (and its dose) and use of LABA.

House Dust Mite Subcutaneous Immunotherapy and Lung Function Trajectory in Children and Adolescents with Asthma

Background: Allergen-specific immunotherapy is currently the only disease-modifying treatment for allergic asthma, and it has been shown to improve control of asthma while reducing both drug use and asthma exacerbations. However, its effects on lung function—especially its long-term effects—remain controversial. We aimed to identify factors associated with a possible beneficial effect of allergen-specific immunotherapy on lung function in asthma by retrospectively evaluating the long-term changes in lung function in children with asthma who received house dust mite subcutaneous immunotherapy (HDM-SCIT). Methods: We enrolled children with asthma who had undergone HDM-SCIT for more than 1 year. Clinical information and lung function measurements were retrieved from the electronic chart system. To characterize the trajectory of lung function change, we performed linear regression analysis to evaluate the maximal expiratory flow at 50% of the forced vital capacity during two periods: before and during HDM-SCIT. Slopes from a least-squares regression line for the two periods, i.e., S1 before HDM-SCIT and S2 during HDM-SCIT, were compared. The subjects were then classified into two groups: an improving group (Group I) defined as S2 − S1 > 0, and a declining group (Group D) defined as S2 − S1 < 0. The clinical factors at the start of HDM-SCIT were compared between the two groups. Results: A total of 16 patients were analyzed. Eight patients were classified into each of Group I and Group D. The mean ages were 10.5 and 11.8 years, and the mean treatment periods were 4.1 and 3.9 years. Group I had a significantly lower blood eosinophil count and a significantly higher HDM-specific IgE level than Group D. Logistic regression showed a strong relationship between those two markers and the lung function trajectory. Conclusion: Control of the blood eosinophil count in highly HDM-sensitized patients may increase the beneficial effect of HDM-SCIT on lung function.

Pulmonary function of healthy Korean children from three independent birth cohorts: Validation of the Global Lung Function Initiative 2012 equation

BACKGROUND AND OBJECTIVE

Global Lung Function Initiative (GLI) 2012 equations were developed to resolve the age-related disparity in interpreting spirometry results. Local validation of the equation is needed, especially in Northeast Asian children. This study evaluated the GLI equation in Korean children.

METHODS

Spirometry indices (FEV1, FVC, FEV1/FVC, and FEF25%-75%) and clinical information were gathered from three population-based birth cohorts. Predicted GLI reference values and z scores of spirometry results were calculated for 1239 healthy children. The mean, standard deviation of z scores were compared with the expected 0 and 1. Probabilities of falling below the lower limit of normal (LLN) (z score: -1.64) were compared with the expected value 5%. GLI z scores were assessed according to low (<-2), normal (≥-2 and ≤2), and high (>2) BMI z score groups.

RESULTS

Mean z scores significantly differed from 0 for FEV1/FVC in males (mean [95% confidence interval]: 0.18 [0.08, 0.27]) and forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) in females (-0.23 [-0.31, -0.15] and -0.26 [-0.36, -0.16], respectively). The standard deviation was larger than 1 for all variables in males and FVC and FEV1/FVC in females. The probability of falling below the LLN was significantly larger than 5% for FEV1 (12.13% [9.64, 14.77]), FVC (15.86% [13.06, 18.81]), and forced expiratory flow at 25%-75% of forced vital capacity (FEF25%-75%) (7.31% [5.29, 9.49]) in males and FVC (11.91% [9.40, 14.60]) in females. FEV1 and FVC z scores increased across low to high body mass index (BMI) groups, and FEV1/FVC decreased from low to high BMI groups.

CONCLUSION

GLI equations marginally differ from real-world values, which should be considered by pulmonologists in practice or research.

Three-dimensional reconstruction image by biplanar stereoradiography reflects pulmonary functional states inadolescent idiopathic scoliosis

This study investigated whether the rib cage parameters estimated based on reconstructed three-dimensional (3D) images with biplanar stereoradiography reflect pulmonary functional states in adolescent idiopathic scoliosis (AIS) patients. A total of 67 Lenke type 1 or 2 AIS patients (59 females and 8 males, mean age 14.4 years) were enrolled. All patients underwent preoperative pulmonary functional tests (PFT) and biplanar stereoradiography. Vital capacity (VC) and forced vital capacity (FVC) pulmonary functional data were collected. Rib-cage parameters (maximum thickness, maximum width, thoracic index (TI), rib hump (RH), rib-cage volume (RCV), spinal penetration index (SPI), endothoracic hump ratio (EHR), vertebra-sternum angle (VSA), rib vertebral angle difference (RVAD), and vertebral lateral decentering (VLD)) were quantified from 3D images. Patients were divided into two groups: restrictive lung disorder (RLD) (%FVC < 80%) and non-RLD (%FVC ≥ 80%). The maximum width and RCV were significantly correlated with VC (p < 0.0001), and FVC (p < 0.0001). RH, EHR, and VSA were negatively correlated with %FVC (p < 0.01). TI, SPI, and RVAD were not correlated with any pulmonary parameters. The maximum widths of RLD patients were significantly shorter than those of the non-RLD patients (218.3 mm vs. 229.7 mm, p < 0.01). The RCV of RLD patients was significantly smaller than that of the non-RLD patients (3.94 L vs. 4.49 L, p < 0.0001). The maximum width and RCV measured by 3D images with biplanar stereoradiography reflected pulmonary functional variables in patients with AIS.

The reference values of peak expiratory flow rate in Thailand children

Background

Daily evaluation of peak expiratory flow rate (PEFR) is quite useful for monitoring and adjusting an asthmatic patient’s treatment. Many factors including geography, ethnicity, socio-economic conditions, gender, and anthropometric play a role in lung function differences studies have found. The aim of this study is to present normal PEFR and to establish a PEFR equation for Thai children living in a suburban environment.

Methods

This study includes a cross-section of healthy children aged 6 to 18. It was conducted in Phitsanulok Province in the lower north of Thailand. The children were chosen to participate from five primary and secondary schools over the period from February 2014 to January 2015. The children were instructed on how to use the Wright peak flow meter (Clement Clarke International Ltd.). All of the participants performed PEFR 3 times and the highest value was recorded.

Results

A total of 2,000 students were initially examined; 80 students were excluded from the study. A total of 1,920 healthy children were recruited between the ages of 6 and18 years. Among them, 719 (37.4%) were males and 1,201 (62.6%) were females. The median age was 18 [12–18] years old, mean height, weight, body mass index (BMI) and PEFR were 155.98±14.99 cm, 51.38±16.95 kg, 20.62±4.79 kg/m² and 339.31±113.55 L/min, respectively. PEFR has a linear relationship in regards age, weight, height and BMI. For males, age was the strongest factor associated with PEFR (r=0.838, P<0.001). Females had a highly significant correlation between height and PEFR (r=0.532, P<0.001). The regression equations are PEFR = (1.34 × height) + (1.41 × weight) + (16.56 × age) – 137.88 for males (R²=0.751, P<0.001) and PEFR = (1.31 × height) + (0.94 × weight) + (7.30 × age) – 55.27 for females (R²=0.507, P<0.001).

Conclusions

This research study has provided the normal range of PEFR for Thai children aged from 6 to 18 years in Phitsanulok. The data was obtained using the Wright peak flow meter. Height, weight, and age were the significant determiners of the PEFR for each sex in the regression equation.

Normal Predicted Reference Values for Spirometry in Korean Children and Adolescents

Pulmonary function tests are useful to evaluate airway obstructions and bronchial responsiveness. We aimed to determine the reference values applicable to Korean children and adolescents. In total, 5590 (2607 males, 2983 females) healthy children aged 4 to 17 years old were recruited from three regions in Korea. Simple and multiple regression analyses were applied using age, height, and weight as variables to predict the forced vital capacity (FVC), forced expiratory volume in one second (FEV1), maximum mid-expiratory flow (MMEF) and the peak expiratory flow rate (PEFR). There were significant correlations between the variables and parameters (P < 0.001). The coefficient of determination (R2) values of polynomial equations with two variables were lower than those with two variables but higher than those of monomial equations based on height. The prediction equations by height were obtained, and the R2 value of the FEV1 was the highest. The predicted spirometric values for males were higher than those for females except for the MMEF. The R2 values for the FEV1 and FVC were higher than previous studies except for the R2 value of the FVC for males in European data. This study provided updated regression equations of normal predicted values for spirometry applicable to Korean children and adolescents.

Effect of Stiffened and Dilated Ascending Aorta on Aerobic Exercise Capacity in Repaired Patients With Complex Congenital Heart Disease

Several studies have reported aortic dilation and increased stiffness of the ascending aorta in patients after repair of congenital heart disease (CHD), which may be a predominant cardiovascular risk. However, the clinical significance has not been described in detail. In this retrospective study, 175 repaired patients with complex CHD achieving biventricular circulation and age-matched 39 control subjects were reviewed (median age: 14.9 and 15.7 years, respectively). We measured the diameters of the ascending aorta and descending aorta from catheterization angiograms to yield Z-scores and stiffness indexes (β) using diameter fluctuations corresponding to pulsatile pressures. Clinical profile, peak oxygen uptake during the cardiopulmonary exercise test, and incidence of unscheduled hospitalization during follow-up was also reviewed. Compared with controls, patients with complex CHD, except for those with aortic coarctation, exhibited significant dilation and increased stiffness of the aortic root and ascending aorta, but not of the descending aorta. In this CHD population (n = 147, including 112 conotruncal anomalies), exercise capacities correlated independently with the diameter Z-score and stiffness index of the ascending aorta along with the history of repetitive thoracotomies, reduced forced vital capacity, and right ventricular hypertension. During a follow-up period (median 15.6 years), either dilation (Z-score >3.5) or increased stiffness (β >6.0) of the ascending aorta stratified morbidity, but no synergistic impact was detected. In conclusion, in repaired patients with complex CHD, a stiffened and dilated ascending aorta was frequently found, exerting significant adverse impacts on diminished exercise capacity and morbidity.

Development of spirometric reference equations for children living at high altitude

OBJECTIVES

This study was aimed to provide locally derived spirometric equations from a population of healthy children residing in Bogota, Colombia, a high-altitude city.

METHODS

Healthy children aged more than 6 years up to less than 18 years underwent spirometry from January 2017 to January 2018, following the recommendations made by the American Thoracic Society/European Respiratory Society (ATS/ERS) Task Force. We performed stepwise multiple regression analyses to predict each spirometric parameter. We also performed extensive residual analyses comparing the measured values with those calculated with our new spirometric equations and with other commonly used equations.

RESULTS

Predictive equations for each spirometric variable were derived from 326 spirometric tests (149 boys, 177 girls). Our newly derived spirometric equations provided the minimum of median of prediction error for almost all spirometric indices measured.

CONCLUSION

We recommend the newly developed spirometric equations for assessing the ventilatory function of children living in Bogota, Colombia.

Factors affecting spirometry reference range in growing children

OBJECTIVES

To find out the association of weight, height and age with spirometry variables and to generate a regression equation by taking weight as an independent variable beside age and height among children and adolescents of Karachi.

METHODS

A modified form of ISSAC questionnaire was used. The spirometry variables recorded were Forced vital capacity (FVC), Forced expiratory volume in 1 second (FEV1), FEV1/FVC, Peak expiratory flow rate (PEF), Forced expiratory flow between 25% and 75% expired volume (FEF25-75). A person's correlation coefficient among boys and girls were calculated for all spirometry variable considering age, height and weight as independent variables. The linear regression models were calculated.

RESULTS

The results reported a linear correlation of lung function variables with all three independent variables (i.e. p-value = 0.000), in which age and height manifested a strong positive correlation while weight reported a moderately significant correlation. All spirometry variables such as FVC, FEV1, PEF and FEF25-75 reported a significant coefficient of dependency and coefficient of correlation individually with age, height and weight.

CONCLUSION

It is concluded that beside age, height and weight both also have significant correlation with lung volumes so these should be taken into account when using spirometry as a diagnostic test.

Physical fitness of non-disabled school-aged children born with extremely low birth weights

BACKGROUND

The assessment of long-term outcomes in survivors born with extremely low birth weights (ELBWs) has become increasingly important. However, little has been reported on the physical fitness of non-disabled school-aged children born with ELBWs.

AIMS

To assess the physical fitness of non-disabled school-aged children born with ELBWs.

STUDY DESIGN

Retrospective cohort study.

SUBJECTS

We analyzed 169 ELBW infants without cerebral palsy or intellectual disability (based on the Wechsler Intelligence Scale for Children-Third Edition (WISC-III) Full Scale intelligence quotient (IQ) test < 70).

OUTCOME MEASURES

Physical fitness was assessed using the grip strength, sit-up repetitions, sit & reach, side steps, standing long jump, and softball throw tests. T-scores were calculated using national survey data.

RESULTS

The T-scores for the grip strength, sit-up repetitions, sit & reach, side steps, standing long jump, softball throw tests, and the overall T-score were 43.7 ± 7.5, 44.2 ± 10.5, 46.0 ± 9.7, 40.9 ± 8.0, 40.0 ± 9.8, 42.4 ± 8.1, and 42.9 ± 5.5, respectively. After adjusting for other age-related factors, the height (SD score), WISC-III Performance IQ score, and percent predicted forced vital capacity (FVC) independently predicted the overall T-scores. Their standardized partial regression coefficients (β) were 0.334 (p = 0.009), 0.190 (p = 0.022), and 0.187 (p = 0.032), respectively.

CONCLUSIONS

Our cohort's physical fitness at approximately 8 years of age was significantly impaired compared to average Japanese children of the same age. Height, FVC, and Performance IQ independently predicted physical fitness, with height being the strongest predictor.

Peak expiratory flow among healthy children aged 5-14 years in China

Background

Guidelines of the Global Initiative for Asthma recommend the use of peak expiratory flow (PEF) in the assessment and management of patients with asthma. However, normal PEF values for Chinese children have not been thoroughly investigated.

Methods

This was a cross-sectional study of 3,169 healthy children aged 5-14 years from research centers in five cities of China: Guangzhou, Suzhou, Chengdu, Xi'an, and Beijing. We established pediatric reference values for PEF using a mini peak flow meter. PEF values recorded by the mini peak flow meter were compared with those obtained using a spirometer.

Results

Height was the biometric variable with greatest correlation to PEF for both sexes. Significant differences were noted between males and females. The regression equation for boys was calculated as PEF =4.39× height (cm) -300.48 (R² =0.76, P<0.001); for girls, this equation was PEF =4.13× height (cm) -278.04 (R² =0.72, P<0.001). PEF values for Chinese children according to age were close to those of Irish, Turkish, and British children but were lower than those of children in Greece; PEF values according to height were similar to those of Turkish and Danish children but lower than values for children in Ireland.

Conclusions

We established normal PEF values and developed predictive equations using linear regression analysis for Chinese children aged 5-14 years, while Greece and Ireland references were inappropriate for Chinese children.

Collating Spirometry reference values in Asian children and Adolescents; puzzle out the reasons for variations

Lung function tests are essential for the diagnosis and management of different respiratory tract diseases; among them the spirometry is the gold standard technique. The accurate diagnosis, management and monitoring require proper interpretation of the results which depends upon the availability of spirometry reference data for that particular region to differentiate the diseased condition from the normal ones. Multiple studies had been done to find out their own area specific reference ranges but it is still lacking. This need was fulfilled by the Global Lung Function Initiative (GLI) in 2012, which reported the first global spirometry equation for all of the age groups. But some of the studies reported difference among GLI reference range and the measured range for that particular region. So here is the review of the reference ranges among 35,603 Asian children and adolescents from the 32 studies done specifically in Asia. The aim was to compare them with the study done by GLI team, along with these, tried to rule out the causal factor that are responsible for the variations in the reference ranges among the children and adolescents of different population. The literature was searched by using Google scholar and PubMed during the month of March up to July 2017. The review of all the articles published in Asia, specifically accounting for normal reference ranges in children and adolescent exhibit a wide variation among the reference ranges. This also suggest involvement of multiple modifiable and non-modifiable risk factors. So it's necessary to update the reference ranges for spirometry and its prediction equation as well.

Longitudinal impairment of lung function in school-age children with extremely low birth weights

OBJECTIVES

To assess lung function and long-term respiratory outcomes in extremely low birth weight (ELBW) survivors.

WORKING HYPOTHESIS

ELBW, especially with respiratory complications in the neonatal period, affects lung function at a later age.

STUDY DESIGN

Longitudinal retrospective study.

PATIENT-SUBJECT SELECTION

Lung function was evaluated in 89 ELBW survivors (at ages 8 and 12) with or without a history of bronchopulmonary dysplasia (BPD) or a bubbly/cystic lung appearance in the neonatal period.

METHODOLOGY

FVC, FEV₁ , FEF₅₀ , and FEF₇₅ were measured using spirometry. Two-way repeated-measures ANOVA was used to compare lung function and deterioration time course from 8 to 12 years of age.

RESULTS

Lung function variables were significantly and positively correlated between 8 and 12 years: %FVC (R²  = 0.558), %FEV₁ (R²  = 0.539), %FEF₅₀ (R²  = 0.412), and %FEF₇₅ (R²  = 0.429). Lung function values were lower than Japanese reference values, especially in children with a history of severe BPD or a bubbly/cystic appearance. %FEV₁ and FEV₁ /FVC ratio worsened from 8 to 12 years of age: 83.0 ± 17.0% versus 76.6 ± 17.8% (mean difference, 95%CI: -6.43, -9.10 to -3.75) and 84.0 ± 10.1% versus 78.2 ± 13.4% (mean difference, 95%CI: -5.82, -8.56 to -3.08), regardless of whether or not there was a history of neonatal respiratory disease.

CONCLUSIONS

In ELBW survivors, the obstructive pattern of lung function impairment deteriorated from 8 to 12 years of age, independent of the presence of severe BPD or bubbly/cystic appearance in the neonatal period.

Long-term safety, efficacy, pharmacokinetics and pharmacodynamics of omalizumab in children with severe uncontrolled asthma

BACKGROUND

Omalizumab is effective and well-tolerated in children with moderate to severe allergic asthma. However, the effects of long-term treatment with omalizumab in this population haven't been well investigated. The objective of this study is to evaluate the long-term safety, efficacy, pharmacokinetics and pharmacodynamics of omalizumab in children with uncontrolled severe asthma.

METHODS

Thirty-eight Japanese children (aged 7-16 years) who completed the 24-week treatment core study were included in an uncontrolled extension study, in which treatment with omalizumab continued until the pediatric indication was approved in Japan (ClinicalTrials.gov number: NCT01328886).

RESULTS

Thirty-five patients (92.1%) completed the extension study. The median exposure throughout the core and extension studies was 116.6 weeks (range, 46.9-151.1 weeks). The most common adverse events were nasopharyngitis, influenza, upper respiratory tract infection, and asthma. Serious adverse events developed in 10 patients (26.3%), but resolved completely with additional treatments. Incidence of adverse events didn't increase with extended exposure with omalizumab. Twenty-nine patients (76.3%) achieved completely- or well-controlled asthma compared with 9 patients (23.7%) at the start of the extension study. QOL scores, the rates (per year) of hospitalizations and ER visits were significantly improved compared with the baseline of the core study [39.0 vs 48.0 (median), p < 0.001 for QOL, 1.33 vs 0.16, p < 0.001 for hospitalization, 0.68 vs 0.15, p = 0.002 for ER visits]. Remarkably, the mean total IgE level showed a decreasing trend while exposure to omalizumab remained at steady-state.

CONCLUSIONS

Long-term treatment with omalizumab is well-tolerated and effective in children with uncontrolled severe allergic asthma. No new safety findings were identified.

Caregiver treatment satisfaction is improved together with children's asthma control: Prospective study for budesonide monotherapy in school-aged children with uncontrolled asthma symptoms

BACKGROUND

If asthmatic children cannot obtain sufficient control of their disease, not only do they suffer from asthma symptoms, but the daily life activities of their caregivers are also disrupted. We investigated the effectiveness of an inhaled corticosteroid (ICS) for symptom control in previously ICS-untreated school-aged asthmatic children as well as caregiver treatment satisfaction (CTS).

METHODS

A multicenter, open-label, single-arm study on 12-week ICS (budesonide Turbuhaler®) monotherapy was undertaken in subjects aged 5-15 years with bronchial asthma not treated with ICS during the previous 3 months. At 0, 4, 8, and 12 weeks after start of ICS administration, Japanese Pediatric Asthma Control Program (JPAC) scores, and CTS scores were summated and lung function measured. At weeks 0 and 12, questionnaires on caregiver anxiety were also assessed.

RESULTS

Seventy-five patients were enrolled, and 69 assessed. Ninety percent of subjects had been treated with asthma controller medication except ICS before study enrollment. JPAC score and CTS score were improved significantly at weeks 4, 8, and 12 (p < 0.001). With regard to CTS, more than half of caregivers showed a perfect score at weeks 8 and 12. There was a significant correlation between JPAC score and CTS score. Lung function and caregiver anxiety were also improved, and good compliance with treatment was observed during the intervention.

CONCLUSIONS

If treating ICS-untreated school-aged asthmatic children with uncontrolled symptoms, ICS monotherapy can improve CTS along with improving asthma control.

Spirometric reference values for healthy Han children aged 5-15 years in Guangzhou, southern China

BACKGROUND

Reliable interpretation of spirometry rests on appropriate reference values, but there are few published reference values for healthy children in China.

OBJECTIVE

To develop the updated spirometric normative values for healthy children aged 5-15 years in Guangzhou, southern China, and to explore the differences by comparison with published reference values.

METHODS

In this cross-sectional study, health questionnaire and physical examination conducted for screening healthy Han children. Spirometry was performed by well-trained technicians according to American Thoracic Society guidelines. Using Lambda-Mu-Sigma (LMS) algorithm, predicted equations for the median and lower limits of normal were derived for forced vital capacity (FVC), forced expiratory volume in one second (FEV1 ), peak expiratory flow (PEF), and maximal mid-expiratory flow (FEF25-75% ). Predicted values were compared with other published spirometric reference equations.

RESULTS

Data were obtained from 422 healthy children (226 boys and 196 girls) aged 5-15 years. Spirometric parameters showed moderate-to-strong positive correlations with age, height, and weight in both genders, with height being the most crucial predictor. There were significant differences between spirometric values and other published reference values. Spirometric values were comparable with the data derived from the same area population in 2002, with exception of increased height and weight in the equivalent age groups.

CONCLUSIONS

The present spirometric reference equations are feasible for assessment of lung function among children in southern China. Further studies for establishment of reference values for Chinese children in other regions are needed.

Perinatal factors associated with long-term respiratory sequelae in extremely low birthweight infants

OBJECTIVE

To assess lung function at 8 years old in extremely low birthweight (ELBW) survivors and to identify perinatal determinants associated with impaired lung function.

DESIGN

Retrospective cohort study.

SETTING

Level III neonatal intensive care unit.

PATIENTS

ELBW survivors born in 1990-2004 with available spirometry at 8 years old were studied. Children were excluded if they had a Wechsler Intelligence Scale for Children Third Edition full IQ <70.

MAIN OUTCOME MEASURES

Multivariate logistic regression analysis was used to identify perinatal determinants associated with airway obstruction (forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) ratio <80%) at school age and the predictive power of potential determinants. Potential risk factors and predictors assessed in this study were gestational age, birth weight, small for gestational age, sex, chorioamnionitis, premature rupture of membranes, antenatal steroids, surfactant administration, respiratory distress syndrome, postnatal steroids, severe bronchopulmonary dysplasia and bubbly/cystic appearances of the lungs by X-ray during the neonatal period.

RESULTS

Of 656 ELBW survivors, 301 (45.9%) had attended a school-age follow-up at 8 years old. A total of 201 eligible children completed the lung function test. Bubbly/cystic appearance of the lungs (OR 4.84, 95% CI 1.26 to 18.70) was associated with a low FEV1/FVC ratio. Children with bubbly/cystic appearance had characteristics of immaturity and intrauterine inflammation.

CONCLUSIONS

Within a cohort of ELBW infants, a bubbly/cystic appearance of the lungs in the neonatal period was the strongest determinant of a low FEV1/FVC ratio at school age.

First Report of FVC and FEV1 Reference Values for Beninese Children Aged 11–16 Years

Background. The diagnosis of obstructive ventilatory disorders in children in Benin is not reliable despite the inclusion of ethnic correction factors for European standards (ERS-93) and the use of African-American standards (ITS-Black). Objectives. (1) Define standard values for forced vital capacity (FVC) and forced expiratory volume in the first second (FEV1) and (2) compare the FVC and FEV1 values observed in study subjects to those calculated by the ERS-93 and ITS-Black equations. Methods. FVC and FEV1 were measured using the MicroQuark Spirometer (Cosmed, Italy), and standing height was measured in 274 Beninese boys and 210 Beninese girls. The means and 95% confidence intervals for these values were calculated by univariate analysis. Results. FVC and FEV1 values calculated using the ERS-93 equations were significantly higher () than the measured values from our study. The percent change between the standard values in our study and the standards calculated using the ERS-93 and ITS-Black equations revealed differences between Beninese children and children of European or African-American descent. Conclusion. The differences observed between study samples and those derived from the ITS-Black and the ERS-93 equations should be used as ethnic correction factors.