FEV1 Z-score Research Articles

Impact of Improved Air Quality and Genetics on Aging Lungs

Introduction: The beneficial effect of a reduction of outdoor air pollution on lung function in the elderly remains unclear, and scarce data exist regarding the modifying effect of genetics. We examined associations between decline in air pollutants (nitrogen oxides [NO2, NOx], particulate matter [PM2.5, PM10] exposure) and lung function measures and their interaction with lung function related risk alleles in elderly German women.Methods: Data were analyzed from the SALIA study (Study on the influence of Air pollution on Lung function, Inflammation and Aging; N=601). Spirometry (FEV1, FVC) was conducted at baseline (1985-1994; all women 55 years of age), first follow-up (2007-2010) and second follow-up (2012-2013). Air pollution concentrations at home addresses were determined for each time of investigation using land-use regression models and extrapolation procedures. GLI (Global Lung Initiative) age and height standardized z-scores were calculated. Weighted genetic risk scores (GRS) were determined from lung function related risk alleles and used to investigate their interaction with improved air quality. Adjusted linear mixed models were fitted.Results: FEV1 and FVC were below predicted values at baseline (mean z-scores<0) but z-scores increased on follow-up. Air pollution levels fell during the study period (e.g. NO2 from a median of 33.4 to 19.7 µg/m3). Reduction of air pollution was associated with an increase of z-scores for FEV1 and FEV1/FVC. For a decrease of 10 µg/m3 in NO2, the z-score for FEV1 increased by 0.14 (95%CI: [0.01; 0.26]). However, with an increasing number of lung function related risk alleles, the benefit from improved air quality decreased (interaction between improved air quality (NO2) and GRS: p=0.029).Conclusions: Reduction of air pollution is associated with a relative improvement of lung function, still on-going in subjects >75 years. However, the beneficial effects of improved air quality also depend on the genetic make-up.

Prenatal, Early-Life and Lifetime Exposure to Air Pollution and Childhood Lung Function and Asthma: The Avon Longitudinal Study of Parents and Children (ALSPAC) Cohort Study

Background: Only a few studies have investigated early-life air pollution exposures on childhood lung function and asthma, with inconsistent results. We examined associations of exposure to air pollution during pregnancy, infancy and lifetime periods with lung function and current asthma in the Avon Longitudinal Study of Parents and Children (ALSPAC) cohort.Methods: Forced expiratory volume in 1 second (FEV1) and Forced vital capacity (FVC) were measured at age 8 years and converted into age-height-gender adjusted z-scores. Current asthma was derived from answers to relevant questionnaire items. Exposures to source-specific particulate matter with a diameter≤10µm (PM10) during each trimester, 0-6 months, 7-12 months (1990-1993) through childhood up to age 8 years (1991-2001) were estimated using a dispersion model, accounting for residential mobility. Linear and logistic regression models were fitted to explore the associations, adjusting for gestational age, damp and mould at home, passive smoking exposure, home ownership, maternal education and smoking during pregnancy.Results: 13,963 study children were included in this analysis. At age 8 years, exposure to interquartile (IQR) higher PM10 (0.72µg/m3) from road traffic during the first trimester was associated with lower FEV1 (-0.05, 95%CI:-0.08 to -0.02) and FVC (-0.05, 95%CI:-0.08 to -0.02) z-scores. Similar significant associations were also seen with PM10 in the second and third trimester, 0-6months, 7-12 months and 0-7 years. Associations were stronger among children whose mother had a lower education level or smoked during pregnancy. PM10 from all sources during the third trimester was significantly associated with lower FVC z-scores. Current asthma was not associated with PM10 at any time periods.Conclusion: Preliminary results suggested that exposure to road-traffic PM10 from as early as in the first trimester may result in small but significant reductions in lung function at age 8 years.

Characterising the nutritional status of children with primary ciliary dyskinesia

Primary ciliary dyskinesia (PCD) is a rare, heterogeneous genetic disorder where impaired mucociliary clearance is caused by dysfunctional motile cilia leading to bronchiectasis. There is limited evidence characterising the nutritional status of children with PCD, although lower body mass index (BMI) z-score has been associated with worse lung function (FEV1). All children (n=43) with PCD, aged <16 years, from a single tertiary centre were prospectively enrolled. Information on clinical phenotype and nutritional status including bioelectrical impedance spectroscopy (BIS) phase-angle was collected. There was a weak positive association between height-for-age z-score (HAZ) and FEV1 z-score (n=28, r=0.4, p=0.049). Those with a low fat free mass index (<-2 z scores) had a lower BMI z score (-1.3±1.2 vs. 0.8±0.7, p=0.0002). BIS phase angle identified more patients at nutritional risk than using moderate malnutrition cut-offs of either HAZ or BMI≤-2 z scores alone (21% vs. 4.6% vs. 6.9% respectively). PCD patients had a higher incidence of vitamin D insufficiency (<50nmoL/L) (54%) and deficiency (<30nmoL/L) (26%) than healthy children. We have characterised the nutritional phenotype of a cohort of children with PCD. Monitoring vitamin D levels is important in PCD patients. There is a weak association between lung function and nutritional status, and measures of BIS phase-angle. The use of BIS phase-angle may allow for early identification of at risk children and may therefore be of benefit for nutritional assessments in the clinical setting. These findings will help inform a future nutritional intervention strategy in children with PCD.

Prenatal nitrate air pollution exposure and reduced child lung function: Timing and fetal sex effects

BackgroundPrenatal particulate air pollution exposure may alter lung growth and development in utero in a time-sensitive and sex-specific manner, resulting in reduced lung function in childhood. Such relationships have not been examined for nitrate (NO3-). MethodsWe implemented Bayesian distributed lag interaction models (BDLIMs) to identify sensitive prenatal windows for the influence of NO3- on lung function at age 7 years, assessing effect modification by fetal sex. Analyses included 191 mother-child dyads. Daily ambient NO3- exposure over pregnancy was estimated using a hybrid chemical transport (Geos-Chem)/land-use regression model. Spirometry was performed at mean (SD) age of 6.99 (0.89) years, with forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) z-scores accounting for child age, sex, height and race/ethnicity. ResultsMost mothers were Hispanic (65%) or Black (22%), had ≤ high school education (67%), and never smoked (71%); 17% children had asthma. BDILMs adjusted for maternal age and education and child's asthma identified an early sensitive window of 6–12 weeks gestation, during which increased NO3- was significantly associated with reduced FEV1 z-scores specifically among boys. BDLIM analyses demonstrated similar sex-specific patterns for FVC. ConclusionEarly gestational NO3- exposure is associated with reduced child lung function, especially in boys.

Airflow Obstruction Categorization Methods and Mortality.

Current guidelines recommend using forced expiratory volume in 1 second (FEV1) % predicted to categorize the severity of airflow obstruction. There are limitations to using FEV1 % predicted for this purpose, including bias associated with demographic factors and the inability to correct for "lung size." Other methods for grading the severity of airflow obstruction have been proposed to address these limitations. Our objectives were to categorize airflow obstruction severity using these methods and then determine which method results in a categorization most closely associated with mortality. Study subjects were patients aged 40-80 years tested in our pulmonary function test laboratories in the period 2002 to 2013 with airflow obstruction based on an FEV1/forced vital capacity (FVC) less than the lower limit of normal. Categorization of airflow obstruction severity was determined using four methods: FEV1 % predicted; FEV1 % predicted adjusted by FVC % predicted; FEV1/FVC confidence interval approach; and FEV1 z-scores. Receiver operating characteristic curve analysis was used to determine which categorization method best predicts 5-year survival. We identified 2,000 patients with airflow obstruction. Important differences in the categorization of airflow obstruction severity were observed using the different methods. More patients were categorized as having severe obstruction using FEV1 % predicted and FEV1 z-scores compared with FEV1 % predicted adjusted by FVC % predicted and FEV1/FVC confidence interval approach. FEV1 % predicted was the best predictor of 5-year survival among the four methods studied. In our study, categorizing airflow obstruction severity using FEV1 % predicted best predicted 5-year survival. This validates the current guideline recommendation that FEV1 % predicted be used to categorize the severity of airflow obstruction.

Childhood predictors of lung function trajectories and future COPD risk: a prospective cohort study from the first to the sixth decade of life

Lifetime lung function is related to quality of life and longevity. Over the lifespan, individuals follow different lung function trajectories. Identification of these trajectories, their determinants, and outcomes is important, but no study has done this beyond the fourth decade. We used six waves of the Tasmanian Longitudinal Health Study (TAHS) to model lung function trajectories measured at 7, 13, 18, 45, 50, and 53 years. We analysed pre-bronchodilator FEV1 z-scores at the six timepoints using group-based trajectory modelling to identify distinct subgroups of individuals whose measurements followed a similar pattern over time. We related the trajectories identified to childhood factors and risk of chronic obstructive pulmonary disease (COPD) using logistic regression, and estimated population-attributable fractions of COPD. Of the 8583 participants in the original cohort, 2438 had at least two waves of lung function data at age 7 years and 53 years and comprised the study population. We identified six trajectories: early below average, accelerated decline (97 [4%] participants); persistently low (136 [6%] participants); early low, accelerated growth, normal decline (196 [8%] participants); persistently high (293 [12%] participants); below average (772 [32%] participants); and average (944 [39%] participants). The three trajectories early below average, accelerated decline; persistently low; and below average had increased risk of COPD at age 53 years compared with the average group (early below average, accelerated decline: odds ratio 35·0, 95% CI 19·5-64·0; persistently low: 9·5, 4·5-20·6; and below average: 3·7, 1·9-6·9). Early-life predictors of the three trajectories included childhood asthma, bronchitis, pneumonia, allergic rhinitis, eczema, parental asthma, and maternal smoking. Personal smoking and active adult asthma increased the impact of maternal smoking and childhood asthma, respectively, on the early below average, accelerated decline trajectory. We identified six potential FEV1 trajectories, two of which were novel. Three trajectories contributed 75% of COPD burden and were associated with modifiable early-life exposures whose impact was aggravated by adult factors. We postulate that reducing maternal smoking, encouraging immunisation, and avoiding personal smoking, especially in those with smoking parents or low childhood lung function, might minimise COPD risk. Clinicians and patients with asthma should be made aware of the potential long-term implications of non-optimal asthma control for lung function trajectory throughout life, and the role and benefit of optimal asthma control on improving lung function should be investigated in future intervention trials. National Health and Medical Research Council of Australia; European Union's Horizon 2020; The University of Melbourne; Clifford Craig Medical Research Trust of Tasmania; The Victorian, Queensland & Tasmanian Asthma Foundations; The Royal Hobart Hospital; Helen MacPherson Smith Trust; and GlaxoSmithKline.

Azithromycin versus placebo for the treatment of HIV-associated chronic lung disease in children and adolescents (BREATHE trial): study protocol for a randomised controlled trial

BackgroundHuman immunodeficiency virus (HIV)-related chronic lung disease (CLD) among children is associated with substantial morbidity, despite antiretroviral therapy. This may be a consequence of repeated respiratory tract infections and/or dysregulated immune activation that accompanies HIV infection. Macrolides have anti-inflammatory and antimicrobial properties, and we hypothesised that azithromycin would reduce decline in lung function and morbidity through preventing respiratory tract infections and controlling systemic inflammation.Methods/designWe are conducting a multicentre (Malawi and Zimbabwe), double-blind, randomised controlled trial of a 12-month course of weekly azithromycin versus placebo. The primary outcome is the mean change in forced expiratory volume in 1 second (FEV1) z-score at 12 months. Participants are followed up to 18 months to explore the durability of effect. Secondary outcomes are FEV1 z-score at 18 months, time to death, time to first acute respiratory exacerbation, number of exacerbations, number of hospitalisations, weight for age z-score at 12 and 18 months, number of adverse events, number of malaria episodes, number of bloodstream Salmonella typhi infections and number of gastroenteritis episodes. Participants will be followed up 3-monthly, and lung function will be assessed every 6 months. Laboratory substudies will be done to investigate the impact of azithromycin on systemic inflammation and on development of antimicrobial resistance as well as impact on the nasopharyngeal, lung and gut microbiome.DiscussionThe results of this trial will be of clinical relevance because there are no established guidelines on the treatment and management of HIV-associated CLD in children in sub-Saharan Africa, where 80% of the world’s HIV-infected children live and where HIV-associated CLD is highly prevalent.Trial registrationClinicalTrials.gov, NCT02426112. Registered on 21 April 2015.

Visceral and subcutaneous abdominal adiposity and pulmonary function in 30-year-old adults: a cross-sectional analysis nested in a birth cohort

BackgroundSeveral studies have verified body fat distribution in association with pulmonary function (PF), mainly waist circumference, but few have used measures able to distinguish abdominal fat compartments. The present study aims to verify the association of visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) with PF measures.MethodsIn 1982, all hospital births occurring in Pelotas, Brazil, were identified and those livebirths have been followed. In 2012–13, the cohort participants were evaluated and VAT and SAT measured using ultrasound; forced expiratory volume in the first second (FEV1) or forced vital capacity (FVC) were patronized in z-scores stratified by sex. The associations were verified using crude and adjusted linear regressions.ResultsThe present analyses comprised 3438 individuals (1721 women). VAT was inversely associated with spirometric parameters, in both crude and adjusted models. SAT showed inverse associations in the crude analyzes in males and a positive trend after adjustment, except for SAT and FVC in males. To each centimeter of VAT, mean adjusted FEV1 z-scores decreased 0.072 (95% CI -0.107; −0.036) in men and 0.127 (95% CI -0.164; −0.090) in women, and FVC z-scores decreased −0.075 (95% CI -0.111; −0.039) and 0.121 (95% CI -0.158; −0.083), in men and women, respectively.ConclusionsVAT has a consistent inverse association with FEV1 and FVC in both sexes. On the other hand, SAT showed inconsistent results with PF parameters.

Ventilatory function as a predictor of mortality in lifelong non-smokers: evidence from large British cohort studies

BackgroundReduced ventilatory function is an established predictor of all-cause mortality in general population cohorts. We sought to verify this in lifelong non-smokers, among whom confounding by active smoking can be...

Lung structure and function similarities between primary ciliary dyskinesia and mild cystic fibrosis: a pilot study

BackgroundPrimary ciliary dyskinesia (PCD) and cystic fibrosis (CF) are increasingly compared. There are no chest magnetic resonance imaging (MRI) comparative studies of PCD and CF. We assessed clinical, functional, microbiological and MRI findings in PCD and mild CF patients in order to evaluate different expression of lung disease.MethodsTwenty PCD (15.1 years) and 20 CF subjects with mild respiratory impairment (16 years, 70% with pancreatic insufficiency) underwent MRI, spirometry, and sputum cultures when clinically stable. MRI was scored using the modified Helbich system.ResultsPCD was diagnosed later than CF (9.9 versus 0.6 years, p = 0.03), despite earlier symptoms (0.1 versus 0.6 years, p = 0.02). In the year preceding the study, patients from both groups underwent two systemic antibiotic courses (p = 0.48). MRI total scores were 11.6 ± 0.7 and 9.1 ± 1 in PCD and CF, respectively. FEV1 and FVC Z-scores were −1.75 (range, −4.6–0.7) and −0.6 (−3.9–1.8) in PCD, and −0.9 (range, −5.4–2.3) and −0.3 (−3.4–2.5) in CF, respectively. No difference was found between lung function or structure, despite a higher MRI subscore of collapse/consolidation in PCD versus CF (1.6 ± 0.1 and 0.6 ± 0.2, p < 0.001). These findings were confirmed after data-control for diagnostic delay. Pseudomonas aeruginosa and Staphylococcus aureus were more frequent in CF than in PCD (p = 0.05 and p = 0.003, respectively).ConclusionsMRI is a valuable radiation-free tool for comparative PCD and CF lung disease assessment. Patients with PCD may exhibit similar MRI and lung function changes as CF subjects with mild pulmonary disease. Delay in PCD diagnosis is unlikely the only determinant of similarities.

Resting Physiological Correlates of Reduced Exercise Capacity in Smokers with Mild Airway Obstruction

ABSTRACTSmokers with minor spirometric abnormalities can experience persistent activity-related dyspnea and exercise intolerance. Additional resting tests can expose heterogeneous physiological abnormalities, but their relevance and association with clinical outcomes remain uncertain. Subjects included sixty-two smokers (≥20 pack-years), with cough and/or dyspnea and minor airway obstruction [forced expiratory volume in one-second (FEV1) ≥80% predicted and >5th percentile lower limit of normal (LLN) (i.e., z-score >−1.64) using the 2012-Global Lung Function Initiative equations]. They underwent spirometry, plethysmography, oscillometry, single-breath nitrogen washout, and symptom-limited incremental cycle exercise tests. Thirty-two age-matched nonsmoking controls were also studied. Thirty-three (53%) of smokers had chronic obstructive pulmonary disease by LLN criteria. In smokers [n = 62; age 65 ± 11 years; smoking history 43 ± 19 pack-years; post-bronchodilator FEV1 z-score −0.60 ± 0.72 and FEV1/FVC z-score −1.56 ± 0.87 (mean ± SD)] versus controls, peak oxygen uptake (̇VO2) was 21 ± 7 vs. 32 ± 9 ml/kg/min, and dyspnea/̇VO2 slopes were elevated (both p < 0.0001). Smokers had evidence of peripheral airway dysfunction and maldistribution of ventilation when compared to controls. In smokers versus controls: lung diffusing capacity for carbon monoxide (DLCO) was 85 ± 22 vs. 105 ± 17% predicted, and residual volume (RV)/total lung capacity (TLC) was 36 ± 8 vs. 31 ± 6% (both p < 0.01). The strongest correlates of peak ̇VO2 were DLCO% predicted (r = 0.487, p < 0.0005) and RV/TLC% (r = −0.389, p = 0.002). DLCO% predicted was also the strongest correlate of dyspnea/̇VO2 slope (r = −0.352, p = 0.005). In smokers with mild airway obstruction, associations between resting tests of mechanics and pulmonary gas exchange and exercise performance parameters were weak, albeit consistent. Among these, DLCO showed the strongest association with important outcomes such as dyspnea and exercise intolerance measured during standardized incremental exercise tests.

Cardiopulmonary exercise testing in children with cystic fibrosis: one centre's experience

BackgroundWhile exercise testing is increasingly used as a prognostic indicator in cystic fibrosis (CF), it is reported to be underused in UK CF centres, particularly in children. Here, we evaluated...

Age Dependency of GLI Reference Values Compared with Paediatric Lung Function Data in Two German Studies (GINIplus and LUNOKID).

A hallmark of the newly published GLI (Global Lungs Initiative) spirometric reference values is their "all-age" (3-95yr) predictive power, accomplished by incorporating non-linear age dependencies into modelling parameters. This modelling strategy is especially promising for the age range of puberty; however, the performance of GLI-values for adolescents is currently unknown. We calculated GLI-based z-scores for children/adolescents without apparent respiratory diseases from two different German studies, LUNOKID (N = 1943, 4–19 years) and GINIplus (N = 1042, 15 years) and determined the goodness of fit for specific age groups. We defined fit sufficient if the absolute mean of z-scores was <0.5. For children (<10yr) the mean GLI-based z-scores for FEV1 and FVC reached a good fit with mean z-scores for FEV1 between -0.11 and 0.01 and mean z-scores for FVC between 0.01 and 0.16, but larger deviations were observed in adolescents, especially boys (mean z-score -0.58 for FEV1 and -0.57 for FVC in GINIplus). The fit for FEV1/FVC was sufficient. GLI reference values provided reasonable estimates for the individuals enrolled in our studies, which span the age range of lung growth and development. However, we found that GLI-predictions overestimated lung volumes, especially those for German adolescent boys, which may, left unrecognised, lead to erroneous diagnosis of lung disease. Caution should be taken when applying these reference values to epidemiologic studies.

EPS04.1 Longitudinal changes in lung clearance index in children with CF

Lung clearance index (LCI), a marker of gas mixing efficiency, is a promising parameter to assess lung function in patients with CF. In cross-sectional data, LCI is often abnormal, even in subjects with normal FEV 1 . Few data are available on long-term evolution of LCI. Objectives LCI was measured prospectively in children with CF during routine follow-up. Changes in LCI were evaluated after 2 years, to explore the magnitude of changes and the relation with changes in FEV 1 . Methods LCI was measured with the Ecomedics Exhalyzer D, using a N 2 washout. Spirometry was performed at the same visit. An LCI higher than 8.3 and a FEV 1 Z-score lower than 1.97 were considered abnormal. Results In 42 patients with a median age of 12.2 years (range 5.8 to 17.2), two measurements were compared with median interval of 21 months (range 18 to 27). At first timepoint (T1), median LCI was 9.4 (range 6.0 to 14.5) and median FEV1 Z-score –0.6 (range –4.1 to 2.0). Over the observation period, individual changes in both parameters occurred, but on the whole major changes were unusual: FEV1 Z-score was normal but LCI was abnormal at T 1 in 23 patients, and this remained so at T2 in 21; both FEV 1 and LCI were normal at T1 in 12 patients, this remained so at T2 in 11; both FEV 1 Z-score and LCI were abnormal at T1 in 7 patients, and this remained so at T 2 in 6. Abnormal FEV 1 and normal LCI was never seen. Conclusion In 23/42 children with CF, FEV1 z-score was normal but LCI z score was abnormal and this remained so 2 years later in all but two subject. These data further support the notion that measuring LCI brings additional information especially in the group of children with normal FEV 1 .

Long-Term Burden and Respiratory Effects of Respiratory Syncytial Virus Hospitalization in Preterm Infants-The SPRING Study.

The health status of premature infants born 321-350 weeks’ gestational age (wGA) hospitalized for RSV infection in the first year of life (cases; n = 125) was compared to that of premature infants not hospitalized for RSV (controls; n = 362) through 6 years. The primary endpoints were the percentage of children with wheezing between 2-6 years and lung function at 6 years of age. Secondary endpoints included quality of life, healthcare resource use, and allergic sensitization. A significantly higher proportion of cases than controls experienced recurrent wheezing through 6 years of age (46.7% vs. 27.4%; p = 0.001). The vast majority of lung function tests appeared normal at 6 years of age in both cohorts. In children with pulmonary function in the lower limit of normality (FEV1 Z-score [-2; -1]), wheezing was increased, particularly for cases vs. controls (72.7% vs. 18.9%, p = 0.002). Multivariate analysis revealed the most important factor for wheezing was RSV hospitalization. Quality of life on the respiratory subscale of the TAPQOL was significantly lower (p = 0.001) and healthcare resource utilization was significantly higher (p<0.001) in cases than controls. This study confirms RSV disease is associated with wheezing in 32-35 wGA infants through 6 years of age.

Evaluation of the global lung function initiative 2012 reference values for spirometry in a Swedish population sample.

BackgroundThe Global Lung Function Initiative 2012 (GLI) reference values are currently endorsed by several respiratory societies but evaluations of applicability for adults resident in European countries are lacking. The aim of this study was to evaluate if the GLI reference values are appropriate for an adult Caucasian Swedish population.MethodsDuring 2008–2013, clinical examinations including spirometry were performed on general population samples in northern Sweden, in which 501 healthy Caucasian non-smokers were identified. Predicted GLI reference values and Z-scores were calculated for each healthy non-smoking subject and the distributions and mean values for FEV1, FVC and the FEV1/FVC ratio were examined. The prevalence of airway obstruction among these healthy non-smokers was calculated based on the Lower Limit of normal (LLN) criterion (lower fifth percentile) for the FEV1/FVC ratio. Thus, by definition, a prevalence of 5% was expected.ResultsThe Z-scores for FEV1, FVC and FEV1/FVC were reasonably, although not perfectly, normally distributed, but not centred on zero. Both predicted FEV1 and, in particular, FVC were lower compared to the observed values in the sample. The deviations were greater among women compared to men. The prevalence of airway obstruction based on the LLN criterion for the FEV1/FVC ratio was 9.4% among women and 2.7% among men.ConclusionsThe use of the GLI reference values may produce biased prevalence estimates of airway obstruction in Sweden, especially among women. These results demonstrate the importance of validating the GLI reference values in different countries.Electronic supplementary materialThe online version of this article (doi:10.1186/s12890-015-0022-2) contains supplementary material, which is available to authorized users.

Adult Respiratory Outcomes of Extreme Preterm Birth. A Regional Cohort Study

Lifetime respiratory function after extremely preterm birth (gestational age≤28 wk or birth weight≤1,000 g) is unknown. To compare changes from 18-25 years of age in respiratory health, lung function, and airway responsiveness in young adults born extremely prematurely to that of term-born control subjects. Comprehensive lung function investigations and interviews were conducted in a population-based sample of 25-year-old subjects born extremely prematurely in western Norway in 1982-1985, and in matched term-born control subjects. Comparison was made to similar data collected at 18 years of age. At 25 years of age, 46/51 (90%) eligible subjects born extremely prematurely and 39/46 (85%) control subjects participated. z-Scores for FEV1, forced expiratory flow at 25-75% of vital capacity, and FEV1/FVC were significantly reduced in subjects born extremely prematurely by 1.02, 1.26, and 0.88, respectively, and airway resistance (kPa/L/s) was increased (0.23 versus 0.18). Residual volume to total lung capacity increased with severity of neonatal bronchopulmonary dysplasia. Responsiveness to methacholine (dose-response slope; 3.16 versus 0.85) and bronchial lability index (7.5 versus 4.8%) were increased in subjects born extremely prematurely. Lung function changes from 18 to 25 years and respiratory symptoms were similar in the prematurely born and term-born groups. Lung function in early adult life was in the normal range in the majority of subjects born extremely prematurely, but methacholine responsiveness was more pronounced than in term-born young adults, suggesting a need for ongoing pulmonary monitoring in this population.

Lung function after spinal fusion for adolescent idiopathic scoliosis

Journal of Paediatrics and Child HealthVolume 51, Issue 3 p. 350-350 Heads UpFree Access Lung function after spinal fusion for adolescent idiopathic scoliosis First published: 11 March 2015 https://doi.org/10.1111/jpc.12858_4AboutSectionsPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Progressive adolescent idiopathic scoliosis has a deleterious effect on lung function and quality of life. There is controversy regarding the benefits of surgical correction and the long-term effect on lung function. A prospective cohort study from a single centre in Edinburgh followed 12 patients (nine women) for a mean of 5.8 years (range 4.1–6.8 years) after combined anterior and posterior spinal fusion.1 Mean thoracic scoliosis was 101 (standard deviation (SD) 15)o pre- and 29 (SD 11)o post-operatively; lumbar scoliosis improved from 79 (range 60–115)o to 29 (SD 18–40)o. The mean forced expiratory volume in 1 s (FEV1) increased from 2.0 to 2.4 L, and the forced vital capacity (FVC) increased from 2.4 to 2.8 L. Both increases were statistically significant, but the children also grew by a mean of 6 cm, and the SD z-scores for FEV1 and FVC were virtually identical before and after surgery. Quality of life measured by questionnaire improved significantly at 2 years and even further at long-term follow-up, irrespective of lung function. This uncontrolled study showed that lung function was preserved following spinal surgery while quality of life improved. Reference 1Urquhart DS et al. Arch. Dis. Child. 2014; 99: 922– 926. CrossrefCASPubMedWeb of Science®Google Scholar Reviewer: David Isaacs, david.isaacs@health.nsw.gov.au Volume51, Issue3March 2015Pages 350-350 ReferencesRelatedInformation

How "healthy" should children be when selecting reference samples for spirometry?

How "healthy" do children need to be when selecting reference samples for spirometry? Anthropometry and spirometry were measured in an unselected, multi-ethnic population of school children aged 5-11 years in London, UK, with follow-up assessments 12 months later. Parents provided information on children's birth data and health status. Forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) were adjusted for sex, age, height and ethnicity using the 2012 Global Lungs Initiative equations, and the effects of potential exclusion criteria on the z-score distributions were examined. After exclusions for current and chronic lung disease, acceptable data were available for 1901 children on 2767 occasions. Healthy children were defined as those without prior asthma or hospitalisation for respiratory problems, who were born at full-term with a birthweight ≥2.5 kg and who were asymptomatic at testing. Mean±sd z-scores for FEV1 and FVC approximated 0±1, indicating the 2012 Global Lungs Initiative equations were appropriate for this healthy population. However, if children born preterm or with low birthweight, children with prior asthma or children mildly symptomatic at testing were included in the reference, overall results were similar to those for healthy children, while increasing the sample size by 25%. With the exception of clear-cut factors, such as current and chronic respiratory disease, paediatric reference samples for spirometry can be relatively inclusive and hence more generalisable to the target population.

Self-reported exercise and longitudinal outcomes in cystic fibrosis: a retrospective cohort study.

BackgroundCystic fibrosis (CF) is characterized by recurrent respiratory infections and progressive lung disease. Whereas exercise may contribute to preserving lung function, its benefit is difficult to ascertain given the selection bias of healthier patients being more predisposed to exercise. Our objective was to examine the role of self-reported exercise with longitudinal lung function and body mass index (BMI) measures in CF.MethodsA total of 1038 subjects with CF were recruited through the U.S. CF Twin-Sibling Study. Questionnaires were used to determine exercise habits. Questionnaires, chart review, and U.S. CF Foundation Patient Registry data were used to track outcomes.ResultsWithin the study sample 75% of subjects self-reported regular exercise. Exercise was associated with an older age of diagnosis (p = 0.002), older age at the time of ascertainment (p < 0.001), and higher baseline FEV1 (p = 0.001), but not CFTR genotype (p = 0.64) or exocrine pancreatic function (p = 0.19). In adjusted mixed models, exercise was associated with both a reduced decline in FEV1 (p < 0.001) and BMI Z-score (p = 0.001) for adults, but not children aged 10–17 years old.ConclusionsIn our retrospective study, self-reported exercise was associated with improved longitudinal nutritional and pulmonary outcomes in cystic fibrosis for adults. Although prospective studies are needed to confirm these associations, programs to promote regular exercise among individuals with cystic fibrosis would be beneficial.Electronic supplementary materialThe online version of this article (doi:10.1186/1471-2466-14-159) contains supplementary material, which is available to authorized users.