Lung Function In Children Research Articles

Traffic-Related Air Pollution (TRAP) in relation to respiratory symptoms and lung function of school-aged children in Kuala Lumpur

ABSTRACT Traffic-Related Air Pollution (TRAP) exposure has been connected to significant health impacts among children. A cross-sectional comparative study was conducted among school children in Malaysia to determine the relationship between their exposure to TRAP and respiratory health effects. Air monitoring was conducted in schools and residences, while the children’s routines were investigated using a diary of daily activities. Respondents’ background and respiratory symptoms were obtained from a validated questionnaire, while a spirometry test was performed to determine their lung function status. The distances between schools and residences from the had contributed to the higher concentration of air pollutants in this study, which had associations with the children’s respiratory symptoms and lung function status. PM2.5 was the main predictor influencing the respondents’ respiratory symptoms and lung function abnormalities. In conclusion, exposure of school children to a high TRAP level might increase their risk of getting respiratory symptoms and lung function reduction.

The acute effects of particulate air pollution on lung function in asthmatic children: A multicenter study with intensively repeated measurements

Evidence on the comparative effects of fine particulate matter (PM2.5) and coarse particulate matter (PM10-2.5) on the lung function of asthmatic children remained limited and inconsistent. This study aims to explore the acute effect of PM2.5 and PM10-2.5 on dynamic forced expiratory volume in 1 s (FEV1) and peak expiratory flow (PEF) among asthmatic children. We conducted a multicenter study and obtained intensively repeated measurements of FEV1 and PEF of clinically diagnosed asthmatic children in 89 Chinese cities from January 2017 to May 2021. Linear mixed-effects models combined with a polynomial distributed lag model were employed to evaluate the cumulative lag effect of PM2.5 and PM10-2.5 on daily FEV1 and PEF among asthmatic children. We also evaluated the effect modifications by sex, age, testing time, season, and region. A total of 590 clinically diagnosed asthmatic children with over 0.18 million dynamic lung function records were included in this study. The adverse effect of particulate matter on lung function occurred in a short term and could last for around one week. Specifically, both PM10-2.5 and PM2.5 were associated with decreases in PEF, but only PM10-2.5 could impair the measurements of FEV1. We found that an interquartile range increase in PM10-2.5 and PM2.5 were associated with 5.40 [95% confidence interval (CI): 0.88, 9.92] mL/s and 10.48 (95%CI: 5.14, 15.81) mL/s decrease in PEF, 6.46 (95%CI: 4.53, 8.40) mL and 0.25 (95%CI: −2.03, 2.54) mL decreases in FEV1, respectively. And the estimated effect of PM10-2.5 was stronger than PM2.5 on FEV1. Besides, these changes were larger in the evening and the south region of China. In conclusion, short-term exposure to both PM2.5 and PM10-2.5 could decrease the daily lung function of asthmatic children. The impact of PM10-2.5 was more hazardous than PM2.5.

Is it time to end race and ethnicity adjustment for pediatric pulmonary function tests?

The continued inclusion of race in spirometry reference equations is a topic of intense debate for adult lung function, but less discussion has focused on implications for children. Obtaining accurate estimates of children's lung function is an important component of the diagnosis of childhood respiratory illnesses, including asthma, cystic fibrosis, and interstitial lung disease. Given the higher burden among racial/ethnic minorities for many respiratory illnesses, it is critical to avoid racial bias in interpreting lung function. We recommend against the continued use of race-specific reference equations for a number of reasons. The original reference populations used to develop the equations were comprised of children with restricted racial diversity, relatively small sample sizes, and likely included some unhealthy children. Moreover, there is no scientific justification for innate racial differences in lung function, as there is no clear physiological or genetic explanation for the disparities. Alternatively, many environmental factors harm lung development, including allergens from pests, asbestos, lead, prenatal smoking, and air pollution, as well as preterm birth and childhood respiratory illnesses, which are all more common among minority racial groups. Race-neutral equations may provide a temporary solution, but still rely on the racial diversity of the reference populations used to build them. Ultimately researchers must uncover the underlying factors truly driving racial differences in lung function.

Effect of Acute PM2.5 Exposure on Lung Function in Children: A Systematic Review and Meta-Analysis.

The objective of this study was to conduct a systematic review and meta-analysis to identify the adverse effects of acute PM2.5 exposure on lung function in children. Systematic review and meta-analysis. Setting, participants and measures: Eligible studies analyzing PM2.5 level and lung function in children were screened out. Effect estimates of PM2.5 measurements were quantified using random effect models. Heterogeneity was investigated with Q-test and I2 statistics. We also conducted meta-regression and sensitivity analysis to explore the sources of heterogeneity, such as different countries and asthmatic status. Subgroup analyses were conducted to determine the effects of acute PM2.5 exposure on children of different asthmatic status and in different countries. A total of 11 studies with 4314 participants from Brazil, China and Japan were included finally. A 10 μg/m3 increase of PM2.5 was associated with a 1.74L/min (95% CI: -2.68, -0.90) decrease in peak expiratory flow (PEF). Since the asthmatic status and country could partly explain the heterogeneity, we conducted the subgroup analysis. Children with severe asthma were more susceptible to PM2.5 exposure (-3.11 L/min per 10 μg/m3 increase, 95% CI -4.54, -1.67) than healthy children (-1.61 L/min per 10 μg/m3 increase, 95% CI -2.34, -0.91). In the children of China, PEF decreased by 1.54 L/min (95% CI -2.33, -0.75) with a 10 μg/m3 increase in PM2.5 exposure. In the children of Japan, PEF decreased by 2.65 L/min (95% CI -3.82, -1.48) with a 10 μg/m3 increase of PM2.5 exposure. In contrast, no statistic association was found between every 10 μg/m3 increase of PM2.5 and lung function in children of Brazil (-0.38 L/min, 95% CI -0.91, 0.15). Our results demonstrated that the acute PM2.5 exposure exerted adverse impacts on children's lung function, and children with severe asthma were more susceptible to the increase of PM2.5 exposure. The impacts of acute PM2.5 exposure varied across different countries.

Lung function and cognitive ability in children: a UK birth cohort study

BackgroundDecreased adult lung function is associated with subsequent impairment in cognition. A similar relationship in early life could be of great policy importance, since childhood cognitive ability determines key adult...

Hyperventilation syndrome in children with asthma

Background Hyperventilation syndrome (HVS) may be associated with asthma. In the absence of a gold standard diagnosis for children, its impact on asthma has been rarely assessed. Objective To assess the impact of HVS on the symptoms and lung function of children with asthma and determine the diagnostic value of the Nijmegen questionnaire in comparison to a hyperventilation test (HVT). Methods Data from asthmatic children followed in the department of Pediatric Pulmonology of Necker Hospital and explored for HVS were retrospectively analyzed. HVS was diagnosed by a positive HVT. Asthma exacerbations, control and lung function were assessed in children with or without a positive HVT. The sensitivity and specificity of the Nijmegen questionnaire were determined relative to the positivity of a HVT. The Nijmegen questionnaire threshold was ≥23. Results Data from 112 asthmatic children, median age 13.9 years [11.6–16], were analyzed. Twenty-eight children (25%) had mild or moderate asthma and 84 (75%) severe asthma. The HVT was performed on 108 children and was negative for 34 (31.5%) and positive for 74 (68.5%). The number of asthma exacerbations in the past 12 months, Asthma Control Test (ACT) score, and lung function did not differ between children with a positive HVT and a negative HVT. The Nijmegen questionnaire was administered to 103 children. Its sensitivity was 56.3% and specificity 56.3%. Conclusion The symptoms and lung function of adolescents with asthma are not affected by the presence of HVS. The sensitivity and specificity of the Nijmegen questionnaire are low.

Effect of radon exposure on asthma morbidity in the School Inner-City Asthma study.

Radon may have a role in obstructive lung disease outside its known carcinogenicity. Little is known about radon's effects on asthma morbidity. To determine the effect of radon on fractional exhaled nitric oxide (FE NO), asthma symptom-days, and lung function in inner-city asthmatic school children. Two hundred ninety-nine school-aged asthmatic children enrolled in the School Inner-City Asthma Study (SICAS-1) were followed. One and two-month averaged radon was assessed using a spatiotemporal model predicting zip code-specific monthly exposures. FE NO and spirometry were measured twice during the academic year. Asthma symptoms were assessed four times during the academic year. The interaction between indoor radon exposure (Bq/m3 ) and seasonality predicting log-transformed FE NO, forced expiratory volume in 1 s (FEV1 ) % predicted, forced vital capacity (FVC) % predicted, FEV1 /FVC, and asthma symptom-days was evaluated. Participants with high radon exposure had greater change in FE NO from warm to cold periods compared to low radon exposure (interaction p = 0.0013). Participants with >50th percentile radon exposure experience significant FE NO increase from warm to cold weather ( = 0.29 [95% confidence interval [CI]: 0.04-0.54], p = 0.0240). We report a positive association between radon 1-month moving average (incidence rate ratio [IRR] = 1.01, p = 0.0273) and 2-month moving average (IRR = 1.01, p = 0.0286) with maximum asthma symptom-days (n = 299, obs = 1167). In asthmatic children, radon may be associated with increased asthma morbidity, suggesting radon may be a modifiable environmental risk factor for airway inflammation.

Individual and joint association of phenols, parabens, and phthalates with childhood lung function: Exploring the mediating role of peripheral immune responses

The functioning of the respiratory system can be interfered with by exposure to mixtures of environmental chemicals, however, the evidence is still ambiguous. We evaluated the association of exposure to mixtures of 14 chemicals, including 2 phenols, 2 parabens, and 10 phthalates, with four major lung function metrics. Based on data from the National Health and Nutrition Examination Survey 2007–2012, this analysis was conducted among 1462 children aged 6–19 years. Linear regression, Bayesian kernel machine regression, quantile-based g-computation regression, and a generalized additive model were performed to estimate the associations. Mediation analyses were performed to investigate plausible biological pathways mediated by immune cells. Our results indicated that the phenols, parabens, and phthalates mixture was negatively related to lung function parameters. And BPA and PP were identified as important contributors to negative associations with FEV1, FVC, and PEF, with non-linear relationships observed between BPA and those outcomes. The most influential factor for a probable FEF25–75 % decline was MCNP. BPA, and MCNP had an interaction effect on FEF25–75 %. The association of PP with FVC and FEV1 has been postulated to be mediated by neutrophils and monocytes. The findings offer insights into the associations of chemical mixtures with respiratory health and the possible driving mechanism, which would be of significance in adding novel evidence of the role of peripheral immune responses, as well as calling for remediation actions to be prioritized during childhood.

Implementation of standardized cystic fibrosis care algorithm to improve the center data-quality improvement project international collaboration

BackgroundA collaboration between the University of Michigan (U of M) Cystic Fibrosis Center (CFC) and Marmara University (MU) CFC was initiated to improve the health status of people with cystic fibrosis (pwCF) at MU through implementing Quality Improvement (QI) initiatives. The main aim was to improve lung function in children with FEV1pp <80. The secondary aim was to assess the changes in health related quality of life. MethodsIncluded in the project were pwCF who received cystic fibrosis (CF) care at the MU CFC and were 6–18 years of age with an FEV1pp <80. Flow charts were created and a standardized CF care algorithm was implemented. Weekly case review were done to develop individualized treatment plans. Appropriate intervention was applied and patient data were assessed at baseline, 3, 6, 9 and 12 months. The Cystic Fibrosis Revised Questionnaire (CFQ-R) was completed. Results55 pwCF were included (mean age:11.8 ± 3.3 years). Mean FEV1pp (SD) at baseline, 6 and 12 month was 63.7 (14.6), 66.9 (16.6), 70.4 (19.2), respectively, with a relative increase of 5.0% in 6 months (p:0.002) and 10.5% in 12 months compared to baseline (p<0.001). Physical functioning, eating problems and respiratory symptoms domains of the CFQ-R questionnaire were improved at the end of the one year for 6–13 (p = 0.024, p = 0.009, p = 0.002) and 13–18 year olds (p = 0.013, p = 0.002, p = 0.038). ConclusionThere was significant improvement in pwCF with FEV1<80%pp after implementing this QI project. The processes and assessments used can be adopted by other low-middle income countries to improve similar measures.

Prenatal Ambient Air Pollutant Mixture Exposure and Early School-age Lung Function.

Analyses included 198 mother-child dyads recruited from two hospitals and affiliated community health centers in Boston, Massachusetts, USA. Daily prenatal pollutant exposures were estimated using satellite-based hybrid chemical-transport models, including nitrogen dioxide(NO2), ozone(O3), and fine particle constituents (elemental carbon [EC], organic carbon [OC], nitrate [NO3 -], sulfate [SO4 2-], and ammonium [NH4 +]). Spirometry was performed at age 6.99 ± 0.89 years; forced expiratory volume in 1s (FEV1), forced vital capacity (FVC), and forced mid-expiratory flow (FEF25-75) z-scores accounted for age, sex, height, and race/ethnicity. We examined associations between weekly-averaged prenatal pollution mixture levels and outcomes using Bayesian Kernel Machine Regression-Distributed Lag Models (BKMR-DLMs) to identify susceptibility windows for each component and estimate a potentially complex mixture exposure-response relationship including nonlinear effects and interactions among exposures. We also performed linear regression models using time-weighted-mixture component levels derived by BKMR-DLMs adjusting for maternal age, education, perinatal smoking, and temperature. Most mothers were Hispanic (63%) or Black (21%) with ≤12 years of education (67%). BKMR-DLMs identified a significant effect for O3 exposure at 18-22 weeks gestation predicting lower FEV1/FVC. Linear regression identified significant associations for O3, NH4 +, and OC with decreased FEV1/FVC, FEV1, and FEF25-75, respectively. There was no evidence of interactions among pollutants. In this multi-pollutant model, prenatal O3, OC, and NH4 + were most strongly associated with reduced early childhood lung function.

A scoping review of lung function in children and adolescents living with HIV in the era of antiretroviral treatment.

Human immunodeficiency virus (HIV) in children and adolescents remains an important health challenge in many countries and is commonly associated with lung disease. The introduction of antiretroviral therapy (ART) has greatly improved survival but chronic lung disease is a common ongoing challenge. We conducted a scoping review of studies that have reported lung function in school-aged children and adolescents living with HIV. A systematic literature search was performed by searching Medline, Embase, and PubMed databases, limited to articles published between 2011 and 2021 in English language. Inclusion criteria were studies involving participants living with HIV aged 5-18 years and having spirometry data. The primary outcome was lung function as measured by spirometry. Twenty-one studies were included in the review. Most study participants were living in the sub-Saharan African region. The prevalence of reduced forced expiratory volume in 1 s(FEV1 ) ranged from 25.3% to 73% across studies, reduced forced vital capacity (FVC) ranged from 10% to 42% and reduced FEV1 /FVC ranged from 3% to 26%. The mean z-score of FEV1 ranged from -2.19 to -0.73, mean zFEV1 /FVC ranged from -0.74 to 0.2, and mean FVC ranged from -1.86 to -0.63. There is a high prevalence of lung function impairment in children and adolescents living with HIV, which persists in the ART era. Further studies are needed of interventions that might improve lung function in these vulnerable populations.

Effect of preoperative pulmonary hemodynamic and cardiopulmonary bypass on lung function in children with congenital heart disease

In children with congenital heart disease (CHD), pulmonary blood flow (Qp) contributes to alterations of pulmonary mechanics and gas exchange, while cardiopulmonary bypass (CPB) induces lung edema. We aimed to determine the effect of hemodynamics on lung function and lung epithelial lining fluid (ELF) biomarkers in biventricular CHD children undergoing CPB. CHD children were classified as high Qp (n = 43) and low Qp (n = 17), according to preoperative cardiac morphology and arterial oxygen saturation. We measured ELF surfactant protein B (SP-B) and myeloperoxidase activity (MPO) as indexes of lung inflammation and ELF albumin as index of alveolar capillary leak in tracheal aspirate (TA) samples collected before surgery and in 6 hourly intervals within 24 h after surgery. At the same time points, we recorded dynamic compliance and oxygenation index (OI). The same biomarkers were measured in TA samples collected from 16 infants with no cardiorespiratory diseases at the time of endotracheal intubation for elective surgery. Preoperative ELF biomarkers in CHD children were significantly increased than those found in controls. In the high Qp, ELF MPO and SP-B peaked 6 h after surgery and tended to decrease afterward, while they tended to increase within the first 24 h in the low Qp. ELF albumin peaked 6 h after surgery and decreased afterwards in both CHD groups. Dynamic compliance/kg and OI significantly improved after surgery only in the High Qp. Conclusion: In CHD children, lung mechanics, OI, and ELF biomarkers were significantly affected by CPB, according to the preoperative pulmonary hemodynamics.What is Known:• Congenital heart disease children, before cardiopulmonary run, exhibit changes in respiratory mechanics, gas exchange, and lung inflammatory biomarkers that are related to the preoperative pulmonary hemodynamics.• Cardiopulmonary bypass induces alteration of lung function and epithelial lining fluid biomarkers according to preoperative hemodynamics.What is New:• Our findings can help to identify children with congenital heart disease at high risk of postoperative lung injury who may benefit of tailored intensive care strategies, such as non-invasive ventilation techniques, fluid management, and anti-inflammatory drugs that can improve cardiopulmonary interaction in the perioperative period.

Dietary patterns, lung function and asthma in childhood: a longitudinal study

BackgroundLongitudinal epidemiological data are scarce examining the relationship between dietary patterns and respiratory outcomes in childhood. We investigated whether three distinct dietary patterns in mid-childhood were associated with lung function and incident asthma in adolescence.MethodsIn the Avon Longitudinal Study of Parents and Children, ‘processed’, ‘traditional’, and ‘health-conscious’ dietary patterns were identified using principal components analysis from food frequency questionnaires at 7 years of age. Post-bronchodilator forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), and forced expiratory flow at 25–75% of FVC (FEF25–75) were measured at 15.5 years and were transformed to z-scores based on the Global Lung Function Initiative curves. Incident asthma was defined by new cases of doctor-diagnosed asthma at age 11 or 14 years.ResultsIn multivariable-adjusted models, the ‘health-conscious’ pattern was positively associated with FEV1 (regression coefficient comparing top versus bottom quartile of pattern score 0.16, 95% CI 0.01 to 0.31, P for trend 0.04) and FVC (0.18, 95% CI 0.04 to 0.33, P for trend 0.02), while the ‘processed’ pattern was negatively associated with FVC (− 0.17, 95% CI − 0.33 to − 0.01, P for trend 0.03). Associations between the ‘health-conscious’ and ‘processed’ patterns and lung function were modified by SCGB1A1 and GPX4 gene polymorphisms. We found no evidence of an association between the ‘traditional’ pattern and lung function, nor between any pattern and FEF25–75 or incident asthma.ConclusionsA ‘health-conscious’ diet in mid-childhood was associated with higher subsequent lung function, while a diet high in processed food was associated with lower lung function.

Evaluation of lung function in a German single center cohort of young patients with sickle cell disease using EIT and standard techniques.

Sickle cell disease (SCD) is a very common autosomal recessive hemoglobinopathy leading to multiple pulmonary complications that are closely associated with mortality. The pathophysiology of chronic pulmonary involvement is not yet fully understood and no specific therapies are available. The aim of this cross-sectional study was to characterize the lung function of children and young adolescents with SCD in a German single-center cohort and to extend conventional lung function testing by the use of a new imaging method. We performed spirometry and body plethysmography in 35 children and young adults with hemoglobin SS, SC, S/β-thalassemia as well as 50 controls. These data were compared with clinical characteristics and typical laboratory parameters of hemolysis and disease activity in SCD. To identify lung inhomogeneities, for example due to atelectasis, hyperinflation, air trapping or vascular occlusions, we used the promising new method of electrical impedance tomography (EIT) and calculated global inhomogeneity indices. Lung function of patients with SCD was significantly reduced compared to that of healthy controls. When the result was found to be pathological, the most commonly observed type of breathing disorder was classified as restrictive. Laboratory parameters showed typical features of SCD including decreased levels of hemoglobin and hematocrit and elevated levels of leucocytes, platelets, lactate dehydrogenase and total bilirubin. However, there was no correlation between blood values and reduced lung function. Electrical impedance tomography (EIT) revealed no abnormalities in SCD patients compared to healthy controls. In particular, we were unable to demonstrate any regional inhomogeneities in lung ventilation. In our study, SCD patients showed impaired lung function, with a relevant percentage of patients suffering from restrictive breathing disorder. Signs of obstruction could not be detected. Electrical impedance tomography (EIT) measurements revealed no unevenness that would suggest air entrapment, blockage of blood vessels, excessive inflation, obstruction, or other forms of lung disease. Additionally, the reduction in lung function observed in SCD patients was not related to the disease severity or laboratory test results.

Pre-natal exposure to NO2 and PM2.5 and newborn lung function: An approach based on repeated personal exposure measurements

ContextWhile strong evidence supports adverse effects of pre-natal air pollution on child's lung function, previous studies rarely considered fine particulate matter (PM2.5) or the potential role of offspring sex and no study examined the effects of pre-natal PM2.5 on the lung function of the newborn. AimWe examined overall and sex-specific associations of personal pre-natal exposure to PM2.5 and nitrogen (NO2) with newborn lung function measurements. MethodsThis study relied on 391 mother-child pairs from the French SEPAGES cohort. PM2.5 and NO2 exposure was estimated by the average concentration of pollutants measured by sensors carried by the pregnant women during repeated periods of one week. Lung function was assessed with tidal breathing analysis (TBFVL) and nitrogen multiple breath washout (N2MBW) test, performed at 7 weeks. Associations between pre-natal exposure to air pollutants and lung function indicators were estimated by linear regression models adjusted for potential confounders, and then stratified by sex. ResultsMean exposure to NO2 and PM2.5 during pregnancy was 20.2 μg/m3 and 14.3 μg/m3, respectively. A 10 μg/m3 increase in PM2.5 maternal personal exposure during pregnancy was associated with an adjusted 2.5 ml (2.3%) decrease in the functional residual capacity of the newborn (p-value = 0.11). In females, functional residual capacity was decreased by 5.2 ml (5.0%) (p = 0.02) and tidal volume by 1.6 ml (p = 0.08) for each 10 μg/m3 increase in PM2.5. No association was found between maternal NO2 exposure and newborns lung function. ConclusionsPersonal pre-natal PM2.5 exposure was associated with lower lung volumes in female newborns, but not in males. Our results provide evidence that pulmonary effects of air pollution exposure can be initiated in utero. These findings have long term implications for respiratory health and may provide insights into the underlying mechanisms of PM2.5 effects.

Prevalence of restrictive lung function in children and adults in the general population

BackgroundRestrictive lung function (RLF) is characterized by a reduced lung expansion and size. In the absence of lung volume measurements, restriction can be indirectly assessed with restrictive spirometric patterns (RSP) by spirometry. Prevalence data on RLF by the golden standard body plethysmography in the general population are scarce. Therefore, we aimed to evaluate the prevalence of RLF and RSP in the general population by body plethysmography and to determine factors influencing RLF and RSP. MethodsPre-bronchodilation lung function data of 8891 subjects (48.0% male, age 6–82 years) have been collected in the LEAD Study, a single-centered, longitudinal, population-based study from Vienna, Austria. The cohort was categorized in the following groups based on the Global Lung Initiative reference equations: normal subjects, RLF (TLC < lower limit of normal (LLN)), RSP (FEV1/FVC ≥ LLN and a FVC < LLN), RSP only (RSP with TLC ≥ LLN). Normal subjects were considered those with FEV1, FVC, FEV1/FVC and TLC between LLN and ULN (upper limit of normal). ResultsThe prevalence of RLF and RSP in the Austrian general population is 1.1% and 4.4%. Spirometry has a positive and negative predictive value of 18.0% and 99.6% to predict a restrictive lung function. Central obesity was associated with RLF. RSP was related to smoking and underweight. ConclusionsThe prevalence of true restrictive lung function and RSP in the Austrian general population is lower than previously estimated. Our data confirm the need for direct lung volume measurement to diagnose true restrictive lung function.

Lung Function of Preterm Children Parsed by a Polygenic Risk Score for Adult COPD

BackgroundChronic obstructive pulmonary disease (COPD) in adults is a result of environmental risk factors and genetic factors. Polygenic COPD risk scores are highly predictive for lung function in adults. We hypothesized that a polygenic COPD risk score is also predictive for lung function in children who are born preterm.MethodsInfants with a birth weight of less than 1500 g (n=17,394) were enrolled in the German Neonatal Network. Among these children, we included those with chip genotyping and 5-year follow-up assessment (n=1957) in this analysis. A polygenic COPD risk score derived in adults with COPD was calculated on the basis of 1,637,882 single-nucleotide polymorphisms associated with forced expiratory volume within 1 second (FEV1) and 1,179,331 single-nucleotide polymorphisms associated with FEV1/FVC (forced vital capacity). This score was related to FEV1, FVC, and FEV1/FVC z scores by linear regression analysis.ResultsAt a mean age at follow-up of 5.8±0.4 years, the polygenic COPD risk score was strongly associated with FEV1 (−0.05 z score/decile, P=6.5 × 10−9) and FEV1/FVC (−0.07 z score/decile, P=4.4 × 10−11) but not FVC. Children in the 10th decile of the polygenic COPD risk score — that is, those at the highest risk — had a mean FEV1 z score of −1.74 (±1.1), indicating lower lung function by these measures and higher rates of obstructive bronchitis.ConclusionsThe upper deciles of a polygenic COPD risk score derived in adults identified a subgroup of children who were born preterm and who are at high risk for obstructive pulmonary disease of prematurity. This finding supports the notion that COPD-associated genes strongly impact lung function in premature children. (Funded by the German Federal Ministry of Education and Research.)

Impulse oscillometry in preschool children with persistent asthma can predict spirometry at school age.

Lung function in children with persistent asthma may be impaired during preschool and school ages. The aim of this study was to describe if some preschool impulse oscillometry(IOS) parameters are related to spirometry alterations on reaching school age. In 66 diagnosed with persistent asthma, an IOS was performed at entrance and followed-up to school age where a spirometry was done. The mean age was 4.9 years at the first evaluation and 7.9 years at the second evaluation, and 59.1% were male. During preschool, R5, R20, Fres, AX, and D5-20 were found to have diagnostic accuracy (area under the curve > 0.7) for predicting abnormal spirometry during school age (defined as FEV1 and/or FEV/FVC and/or FVC values below the lower limit of normality according to Quanjer predictive values). AX, D5-20, and R5 had the best LR+ to increase the probability of abnormal spirometry (50, 10, and 7.1, respectively). R20, R5, and AX was the best IOS parameters for discriminating bronchodilator response (BDR) in schoolchildren (LR+ = 3.4, 2.9, and 2.8, respectively). The findings of this study indicate that some IOS parameters between 3 and 5 years of age are useful for predicting abnormal spirometry and BDR at school age.

Associations between prenatal and early-life air pollution exposure and lung function in young children: Exploring influential windows of exposure on lung development

BackgroundEvidence in the literature suggests that air pollution exposures experienced prenatally and early in life can be detrimental to normal lung development, however the specific timing of critical windows during development is not fully understood. ObjectivesWe evaluated air pollution exposures during the prenatal and early-life period in association with lung function at ages 6–9, in an effort to identify potentially influential windows of exposure for lung development. MethodsOur study population consisted of 222 children aged 6–9 from the Fresno-Clovis metro area in California with spirometry data collected between May 2015 and May 2017. We used distributed-lag non-linear models to flexibly model the exposure-lag-response for monthly average exposure to fine particulate matter (PM2.5) and ozone (O3) during the prenatal months and first three years of life in association with forced vital capacity (FVC), and forced expiratory volume in the first second (FEV1), adjusted for covariates. ResultsPM2.5 exposure during the prenatal period and the first 3-years of life was associated with lower FVC and FEV1 assessed at ages 6–9. Specifically, an increase from the 5th percentile of the observed monthly average exposure (7.55 μg/m3) to the median observed exposure (12.69 μg/m3) for the duration of the window was associated with 0.42 L lower FVC (95% confidence interval (CI): −0.82, −0.03) and 0.38 L lower FEV1 (95% CI: −0.75, −0.02). The shape of the lag-response indicated that the second half of pregnancy may be a particularly influential window of exposure. Associations for ozone were not as strong and typically CIs included the null. ConclusionsOur findings indicate that prenatal and early-life exposures to PM2.5 are associated with decreased lung function later in childhood. Exposures during the latter months of pregnancy may be especially influential.

Lung Function in Children with Primary Ciliary Dyskinesia

Primary ciliary dyskinesia (PCD) is characterized by impaired mucociliary clearance that results in accumulation of mucus and bacteria in the airways. Lower respiratory tract infections lead to airway remodeling and lung function impairment. The aim of our narrative review is to discuss available data on lung function in PCD children, focusing on risk factors for lung function impairment. Relevant published studies searching MEDLINE/Pubmed are included in this narrative review, using these terms: "primary ciliary dyskinesia" and "pulmonary function test" or "spirometry" or "lung function". Filters were language (English) and age of study subjects (0-18 years). The majority of recent published studies showed normal spirometric values in PCD children, even if some authors described a pulmonary impairment. Together with spirometry, Lung Clearance Index has been applied for detecting peripheral airway disease, and it might have a role in early mild lung disease assessment. Studies on lung function trajectories after PCD diagnosis showed a significant heterogeneity, with some patients maintaining reasonably good lung function, whereas others showing a decline. Further studies are needed to analyze lung function prospectively from childhood into adulthood, and to evaluate whether lung function trajectories are affected by PCD clinical phenotype, ultrastructural ciliary defect or genetic background.