Copenhagen Prospective Study On Asthma In Childhood Research Articles

The infant gut virome is associated with preschool asthma risk independently of bacteria.

Bacteriophage (also known as phage) communities that inhabit the gut have a major effect on the structure and functioning of bacterial populations, but their roles and association with health and disease in early life remain unknown. Here, we analyze the gut virome of 647 children aged 1 year from the Copenhagen Prospective Studies on Asthma in Childhood2010 (COPSAC2010) mother-child cohort, all deeply phenotyped from birth and with longitudinally assessed asthma diagnoses. Specific temperate gut phage taxa were found to be associated with later development of asthma. In particular, the joint abundances of 19 caudoviral families were found to significantly contribute to this association. Combining the asthma-associated virome and bacteriome signatures had additive effects on asthma risk, implying an independent virome-asthma association. Moreover, the virome-associated asthma risk was modulated by the host TLR9 rs187084 gene variant, suggesting a direct interaction between phages and the host immune system. Further studies will elucidate whether phages, alongside bacteria and host genetics, can be used as preclinical biomarkers for asthma.

High-dose vitamin D3 supplementation in pregnancy and risk of neurodevelopmental disorders in the children at age 10: A randomized clinical trial

BackgroundVitamin D deficiency in pregnancy may increase the risk of autism and attention deficit hyperactivity disorder (ADHD). ObjectiveThe objective of this study was to estimate the effect of vitamin D3 supplementation in pregnancy on risk of autism and ADHD. DesignThis randomized clinical trial was part of the COpenhagen Prospective Study on Neuro-PSYCHiatric Development (COPYCH) project nested within the Copenhagen Prospective Studies on Asthma in Childhood 2010 (COPSAC2010) cohort comprising a population-based sample of 700 healthy mother-child pairs enrolled at week 24 of pregnancy. Maternal 25-hydroxy-vitamin D (25(OH)D) was measured at inclusion and 623 mothers were randomized 1:1 to either high-dose (2800 IU/d) or standard dose (400 IU/d) vitamin D3 until 1 wk postpartum (315 received high-dose, 308 standard dose). At age 10, diagnoses and symptom load of autism and ADHD, respectively, were established using the Kiddie-Schedule for Affective Disorders and Schizophrenia for School-Age Children-Present and Lifetime Version. ResultsThe psychopathologic evaluation was completed by 591 children aged 10 y, and 16 children (2.7%) were diagnosed with autism and 65 (11.0%) with ADHD. Hereof, 496 children participated in the vitamin D3 trial (246 received high-dose, 250 standard dose). Of these, 12 children (2.4%) were diagnosed with autism and 58 (11.7%) with ADHD. Higher maternal preintervention 25(OH)D levels were associated with a decreased risk of autism [odd ratio (OR) per 10 nmol/L: 0.76 (0.59,0.97); P = 0.034], lower autistic symptom load [β per 10 nmol/L: −0.03 (−0.05,0.00); P = 0.024), and decreased risk of ADHD diagnosis (OR per 10 nmol/L: 0.88 (0.78,0.99); P = 0.033]. High-dose vitamin D3 supplementation was not associated with risk of autism or ADHD. ConclusionsHigher maternal preintervention 25(OH)D was associated with a decreased risk of autism, lower autistic symptom load, and decreased risk of ADHD diagnosis, but high-dose vitamin D3 supplementation in pregnancy had no effect on risk of autism and ADHD.This trial was registered at clinicaltrials.gov as NCT00856947.

Associations of pre- and postnatal exposures with optic nerve status in young adults.

We aimed to explore the effect of multiple pre- and postnatal exposures on optic nerve status in young adults due to this critical period for development. We analysed peripapillary retinal nerve fibre layer (RNFL) status and macular thickness at age 18 years in the Copenhagen Prospective Studies on Asthma in Childhood 2000 (COPSAC2000 ) cohort in relation to several exposures. Of the 269 participants (median (IQR) age, 17.6 (0.6) years; 124 boys), 60 participants whose mothers had smoked during pregnancy had a thinner RNFL: adjusted mean difference -4.6 μm (95% CI -7.7; -1.5 μm, p = 0.004) compared with participants whose mothers had not smoked during pregnancy. A total of 30 participants who were exposed to tobacco smoke both during foetal life and childhood had thinner RNFL: -9.6 μm (-13.4; -5.8 μm, p < 0.001). Smoking during pregnancy was also associated with a macular thickness deficit: -4.7 μm (-9.0; -0.4 μm, p = 0.03). Higher indoor concentrations of particulate matter 2.5 (PM2.5) was associated with thinner RNFL: -3.6 μm (-5.6; -1.6 μm, p < 0.001) and a macular deficit: -2.7 μm (-5.3; -0.1 μm, p = 0.04) in the crude analyses, but not in the adjusted analyses. No difference was found among participants who smoked at age 18 years compared with non-smokers on RNFL or macular thickness. We found that exposure to smoking during early life was associated with a thinner RNFL and macula at age 18 years. The absence of an association between active smoking at 18 years suggests that the vulnerability of the optic nerve is highest during prenatal life and early childhood.

Middle ear effusion, ventilation tubes and neurological development in childhood.

Otitis media with middle ear effusion (MEE) can be treated with ventilation tubes (VT) insertion, and it has been speculated that prolonged MEE in childhood can affect neurological development, which in turn may be important for later academic achievements. To investigate the association between middle ear effusion (MEE), treatment with ventilation tubes (VT) and childhood neurological development. We examined 663 children from the Copenhagen Prospective Studies on Asthma in Childhood 2010 (COPSAC2010) unselected mother-child cohort study. Children were followed by study pediatricians with regular visits from pregnancy until 3 years of age. MEE was diagnosed using tympanometry at age 1, 2 and 3 years. Information regarding VT from age 0-3 years was obtained from national registries. We assessed age at achievement of gross motor milestones from birth, language scores at 1 and 2 years, cognitive score at 2.5 years and general development score at age 3 years using standardized quantitative tests. Children with MEE had a lower 1-year word production vs. children with no disease: (median 2, IQR [0-6] vs. 4, IQR [1-7]; p = 0.017), and a lower 1-year word comprehension (median 36; IQR [21-63] vs. 47, IQR [27-84]; p = 0.03). Children with VT had a lower 2-5-year cognitive score vs. children with no disease; estimate -2.34; 95% CI [-4.56;-0.12]; p = 0.039. No differences were found between children with vs. without middle ear disease regarding age at achievement of gross motor milestones, word production at 2 years or the general developmental score at 3 years. Our study supports the previous findings of an association between MEE and concurrent early language development, but not later neurological endpoints up to the age of 3. As VT can be a treatment of those with symptoms of delayed development, we cannot conclude whether treatment with VT had positive or negative effects on neurodevelopment.

Effects of prenatal nutrient supplementation and early life exposures on neurodevelopment at age 10: a randomised controlled trial - the COPSYCH study protocol

IntroductionNutrient deficiency and immune and inflammatory disturbances in early life may compromise neurodevelopment and be implicated in the aetiology of psychiatric disorders. However, current evidence is limited by its predominantly...

Vertical Transfer of Metabolites Detectable from Newborn's Dried Blood Spot Samples Using UPLC-MS: A Chemometric Study.

The pregnancy period and first days of a newborn’s life is an important time window to ensure a healthy development of the baby. This is also the time when the mother and her baby are exposed to the same environmental conditions and intake of nutrients, which can be determined by assessing the blood metabolome. For this purpose, dried blood spots (DBS) of newborns are a valuable sampling technique to characterize what happens during this important mother-child time window. We used metabolomics profiles from DBS of newborns (age 2–3 days) and maternal plasma samples at gestation week 24 and postpartum week 1 from mother-child pairs of the Copenhagen Prospective Studies on Asthma in Childhood 2010 (COPSAC) cohort, to study the vertical mother-child transfer of metabolites. Further, we investigated how persistent the metabolites are from the newborn and up to 6 months, 18 months, and 6 years of age. Two hundred seventy two metabolites from UPLC-MS (Ultra Performance Liquid Chromatography-Mass Spectrometry) analysis of DBS and maternal plasma were analyzed using correlation analysis. A total of 11 metabolites exhibited evidence of transfer (), including tryptophan betaine, ergothioneine, cotinine, theobromine, paraxanthine, and N6-methyllysine. Of these, 7 were also found to show persistence in their levels in the child from birth to age 6 years. In conclusion, this study documents vertical transfer of environmental and food-derived metabolites from mother to child and tracking of those metabolites through childhood, which may be of importance for the child’s later health and disease.

High-dose vitamin D supplementation in pregnancy and 25(OH)D sufficiency in childhood reduce the risk of fractures and improve bone mineralization in childhood: Follow-up of a randomized clinical trial

SummaryBackgroundExposure to vitamin D in early life has been associated with improved bone mineralization, but no studies have investigated the combined effect of pregnancy supplementation and childhood 25(OH)D concentrations on bone health.MethodsWe analyzed the effect of serum 25(OH)D concentrations at age 6 months and 6 years and the combined effect with prenatal high-dose vitamin D (2800 vs. 400 IU/day) on bone mineral density (BMD) and content (BMC) assessed by dual-energy X-ray absorptiometry (DXA) scans at age 3 and 6 years and longitudinal risk of fractures in a double-blinded, randomized clinical trial in the Copenhagen Prospective Studies on Asthma in Childhood 2010 (COPSAC2010) mother-child cohort with enrollment from March 4, 2009, to November 17, 2010, and clinical follow-up until January 31, 2019 (NCT00856947). All participants randomized to intervention and with complete data were included in the analyses.FindingsAt age 6 months, serum 25(OH)D concentration was measured in 93% (n = 541) of 584 children. Children with sufficient (≥ 75 nmol/l) vs. insufficient (< 75 nmol/l) concentrations did not have lower risk of fractures: incidence rate ratio (95% CI); 0.64 (0.37;1.11), p = 0.11. However, vitamin D sufficient children from mothers receiving high-dose supplementation during pregnancy had a 60% reduced incidence of fractures compared with vitamin D insufficient children from mothers receiving standard-dose: 0.40 (0.19;0.84), p = 0.02.At age 6 years, serum 25(OH)D concentration was measured in 83% (n = 318) of 383 children with available DXA data. Whole-body bone mineralization was higher in vitamin D sufficient children at age 6 years; BMD, adjusted mean difference (aMD) (95% CI): 0.011 g/cm2 (0.001;0.021), p = 0.03, and BMC, aMD: 12.3 g (-0.8;25.4), p = 0.07, with the largest effect in vitamin D sufficient children from mothers receiving high-dose vitamin D supplementation; BMD, aMD: 0.016 g/cm2 (0.002;0.030), p = 0.03, and BMC, aMD: 23.5 g (5.5;41.5), p = 0.01.InterpretationChildhood vitamin D sufficiency improved bone mineralization and in combination with prenatal high-dose vitamin D supplementation reduced the risk of fractures.FundingThe study was supported by The Lundbeck Foundation R16-A1694, The Danish Ministry of Health 903,516, The Danish Council for Strategic Research 0603–00280B and The European Research Council 946,228.

Increasing severity of early-onset atopic dermatitis, but not late-onset, associates with development of aeroallergen sensitization and allergic rhinitis in childhood.

Early exposure to allergens through a defect skin barrier has been proposed as a mechanism for inducing sensitization and development of allergic diseases. We hypothesized that early-onset, severe atopic dermatitis (AD) is associated with development of aeroallergen sensitization and allergic rhinitis. We included 368 children from the Copenhagen Prospective Studies on Asthma in Childhood2000 (COPSAC2000 ) at-risk mother-child cohort. AD was diagnosed prospectively based on Hanifin&Rajka's criteria and severity assessed using the Scoring Atopic Dermatitis (SCORAD) index. Early-onset AD was defined as debut ≤1year, late-onset as debut from 1-6years. Aeroallergen sensitization and allergic rhinitis were diagnosed at ages 6-7 and 12years. Associations between early-onset and late-onset AD and allergy endpoints were calculated using general estimating equations (GEE) models to compute the overall odds ratios (OR) for both time points. Early-onset AD (yes/no) and severity (SCORAD) were associated with development of aeroallergen sensitization during childhood; GEE OR=1.68 [1.08; 2.62], p=.02 and 1.08 [1.03; 1.12], p<.001, whereas late-onset AD showed a borderline significant association and late-onset severity showed no association; GEE OR=1.65 [0.92; 2.94], p=.08 and 1.01 [0.97; 1.06], p=.55. The same trend was seen for allergic rhinitis with significant association between early-onset AD and allergic rhinitis; GEE OR=1.56 [1.01; 2.41], p=.04 and severity; GEE OR=1.09 [1.05; 1.13], p<.001, whereas late-onset AD showed no association. The effects on sensitization and rhinitis of early-onset versus late-onset AD severity were significantly different: p-interactionsensitization =.03 and p-interactionrhinitis <.01. Increasing severity of early-onset AD, but not late-onset AD, associates with aeroallergen sensitization and allergic rhinitis later in childhood.

Prenatal tobacco exposure and risk of asthma and allergy outcomes in childhood.

Harmful effects of prenatal tobacco exposure and possible interaction with 17q12-21 genetic variants have been shown for some asthma outcomes in childhood, whereas findings related to allergy outcomes are more inconsistent. This study aimed to examine the effect of prenatal tobacco exposure and relation to 17q12-21 genotype on a wide array of asthma and allergy-related outcomes in early childhood. Prenatal tobacco exposure was determined by maternal smoking during the third trimester (yes/no) in 411 children from the phenotyped Copenhagen Prospective Studies on Asthma in Childhood 2000 (COPSAC2000) birth cohort with clinical follow-up to age 7 years. The rs7216389 single nucleotide polymorphism was used as main representative of the 17q12-21 locus. Asthma end-points included asthma diagnosis, exacerbations, episodes with troublesome lung symptoms and lower respiratory tract infections, spirometry, plethysmography, bronchial responsiveness to methacholine, exercise and cold dry air. Allergy-related endpoints included aeroallergen sensitisation, allergic rhinitis, fractional exhaled nitric oxide, blood eosinophil count and urine eosinophil protein X levels. Statistical analyses were done using Cox regression, linear regression, logistic regression and quasi-Poisson regression. Prenatal tobacco exposure increased the risk of asthma (adjusted hazard ratio (aHR) 2.05, 95% CI 1.13-3.73; p=0.02), exacerbations (aHR 3.76, 95% CI 2.05-6.91; p<0.001), number of LRTIs (adjusted incidence rate ratio 1.87, 95% CI 1.34-2.55; p<0.001), and was associated with decreased spirometry indices (forced expiratory volume in 1 s (FEV1) adjusted mean difference (aMD) -0.07 L, 95% CI -0.13- -0.005 L, p=0.03; maximal mid-expiratory flow aMD -0.19 L·s-1, -0.34- -0.04 L·s-1, p=0.01) and increased bronchial responsiveness to methacholine (provocative dose of methacholine causing a 20% drop in FEV1 adjusted geometric mean ratio 0.55, 95% CI 0.31-0.96; p=0.04). In contrast, there was no association with any allergy-related end-points. The effect on asthma depended on 17q12-21 genotype with an increased risk only among children without risk alleles. Prenatal tobacco exposure was associated with asthma dependent on 17q12-21 genotype and with exacerbations, lung function and bronchial responsiveness, but not with any allergy-related outcomes. This suggests that tobacco exposure in utero leads to adverse lung developmental/structural effects rather than susceptibility to develop allergy and type 2 inflammation.

Associations between Inhaled Corticosteroid Use in the First 6 Years of Life and Obesity-related Traits.

Rationale: Infants and young children might be particularly likely to experience the potential clinical side effects of inhaled corticosteroids (ICSs) on body mass index (BMI), adiposity rebound (AR), and body composition, but this has rarely been studied in long-term studies in this age group. Objectives: To determine the association between ICS exposure in the first 6 years of life and the BMI, AR, body composition, and blood lipid concentrations. Methods: Children from the two mother-child cohorts of the COPSAC (Copenhagen Prospective Studies on Asthma in Childhood) were included. ICS use was registered prospectively to age 6 years, and the cumulative dose was calculated. Multiple linear regression models were used for analysis. Measurements and Main Results: A total of 932 (84%) of the 1,111 children from the COPSAC cohorts had BMI data, 786 (71%) had dual-energy X-ray absorptiometry scan data at the age of 6 years, and 815 (73%) had an AR age calculated. Two hundred ninety-one children (31%) received a cumulative ICS dose higher than that from 10 weeks of standard treatment before the age of 6. ICS treatment during 0-6 years of age was associated with an increased BMI z-score (0.05 [95% confidence interval, 0.005 to 0.09] SDs per each year of standard treatment; P = 0.03) an earlier age at AR (-0.18 [95% confidence interval, -0.28 to -0.08] yr; P = 0.0006), and a 2% increased geometric mean android fat percentage (P = 0.05). ICS exposure and dual-energy X-ray absorptiometry scan data were not associated. Conclusions: ICS use in early childhood was associated with an increased BMI z-score at age 6, an earlier AR, and a trend of association with an increased android body fat percentage.

The Airway Microbiota Modulates Effect of Azithromycin Treatment for Episodes of Recurrent Asthma-like Symptoms in Preschool Children: A Randomized Clinical Trial.

Rationale: Childhood asthma is often preceded by recurrent episodes of asthma-like symptoms, which can be triggered by both viral and bacterial agents. Recent randomized controlled trials have shown that azithromycin treatment reduces episode duration and severity through yet undefined mechanisms. Objectives: To study the influence of the airway microbiota on the effect of azithromycin treatment during acute episodes of asthma-like symptoms. Methods: Children from the COPSAC2010 (Copenhagen Prospective Studies on Asthma in Childhood 2010) cohort with recurrent asthma-like symptoms aged 12-36 months were randomized during acute episodes to azithromycin or placebo as previously reported. Before randomization, hypopharyngeal aspirates were collected and examined by 16S ribosomal RNA gene amplicon sequencing. Measurements and Main Results: In 139 airway samples from 68 children, episode duration after randomization was associated with microbiota richness (7.5% increased duration per 10 additional operational taxonomic units [OTUs]; 95% confidence interval, 1-14%; P = 0.025), with 15 individual OTUs (including several Neisseria and Veillonella), and with microbial pneumotypes defined from weighted UniFrac distances (longest durations in a Neisseria-dominated pneumotype). Microbiota richness before treatment increased the effect of azithromycin by 10% per 10 additional OTUs, and more OTUs were positively versus negatively associated with an increased azithromycin effect (82 vs. 58; P = 0.0032). Furthermore, effect modification of azithromycin was found for five individual OTUs (three OTUs increased and two OTUs decreased the effect; q < 0.05). Conclusions: The airway microbiota in acute episodes of asthma-like symptoms is associated with episode duration and modifies the effect of azithromycin treatment of the episodes in preschool children with recurrent asthma-like symptoms. Clinical trial registered with www.clinicaltrials.gov (NCT01233297).

High-Dose Vitamin D Supplementation in Pregnancy and Neurodevelopment in Childhood

Observational studies have reported an association between high maternal vitamin D levels and improved neurodevelopment in offspring, but no randomized clinical trial (RCT) has investigated these observations. To determine whether high-dose vitamin D supplementation during pregnancy improves offspring neurodevelopment from birth to age 6 years. This prespecified secondary analysis of a double-blinded, placebo-controlled RCT of high-dose vitamin D3 supplementation vs standard dose during the third trimester of pregnancy was conducted in the unselected prospective mother-child birth cohort at a single-center research unit in Denmark as part of the Copenhagen Prospective Studies on Asthma in Childhood 2010 (COPSAC-2010). Participants included pregnant women; women with vitamin D intake greater than 600 IU/d or an endocrine, heart, or kidney disorder, and those who did not speak Danish fluently were excluded. Neurodevelopmental assessments for offspring of these women were performed at ages 0 to 6 years. Children born prematurely (gestational week <37), with low birth weight (<2500 g), or with a neurological disease affecting neurodevelopment were excluded. Data were analyzed from August 2019 to February 2020. High-dose (ie, 2800 IU/d) vs standard dose (ie, 400 IU/d) vitamin D3 supplementation from pregnancy week 24 until 1 week after birth. The primary outcome of interest was cognitive development assessed at 2.5 years using the Bayley Scales of Infant and Toddler Development. Other neurodevelopmental outcomes included age of motor milestone achievement (Denver Developmental Index and World Health Organization milestone registration), language development (MacArthur-Bates Communicative Development Inventories), general neurodevelopment at age 3 years (Ages and Stages Questionnaire), and emotional and behavioral problems at age 6 years (Strengths and Difficulties Questionnaire). Among 623 women randomized, 315 were randomized to high-dose vitamin D3 and 308 were randomized to standard dose placebo. A total of 551 children were evaluated from birth to age 6 years, (282 [51.2%] boys; 528 [95.8%] White), with 277 children in the high-dose vitamin D3 group and 274 children in the standard dose group. There was no effect of the high-dose compared with standard dose of vitamin D3 supplementation during pregnancy on offspring achievement of motor milestones (β = 0.08 [95% CI, -0.26 to 0.43]; P = .64), cognitive development (score difference: 0.34 [95% CI, -1.32 to 1.99]; P = .70), general neurodevelopment (median [IQR] communication score: 50 [50-55] vs 50 [50-55]; P = .62), or emotional and behavioral problems (odds ratio, 0.76 [95% CI, 0.53 to 1.09]; P = .14). There was no effect on language development expressed by the word production at 1 year (median [IQR], 2 [0-6] words vs 3 [1-6] words; P = .16), although a decreased word production was apparent at 2 years in children in the high-dose vitamin D3 group (median [IQR], 232 [113-346] words vs 253 [149-382.5] words; P = .02). In this prespecified secondary analysis of an RCT, maternal high-dose vitamin D3 supplementation during the third trimester of pregnancy did not improve neurodevelopmental outcomes in the offspring during the first 6 years of life. These findings contribute essential information clarifying the effects of prenatal exposure to vitamin D on neurodevelopment in childhood. ClinicalTrials.gov Identifier: NCT00856947.

FUT2\u2013ABO epistasis increases the risk of early childhood asthma and Streptococcus pneumoniae respiratory illnesses

Asthma with severe exacerbation is the most common cause of hospitalization among young children. We aim to increase the understanding of this clinically important disease entity through a genome-wide association study. The discovery analysis comprises 2866 children experiencing severe asthma exacerbation between ages 2 and 6 years, and 65,415 non-asthmatic controls, and we replicate findings in 918 children from the Copenhagen Prospective Studies on Asthma in Childhood (COPSAC) birth cohorts. We identify rs281379 near FUT2/MAMSTR on chromosome 19 as a novel risk locus (OR = 1.18 (95% CI = 1.11–1.25), Pdiscovery = 2.6 × 10−9) as well as a biologically plausible interaction between functional variants in FUT2 and ABO. We further discover and replicate a potential causal mechanism behind this interaction related to S. pneumoniae respiratory illnesses. These results suggest a novel mechanism of early childhood asthma and demonstrates the importance of phenotype-specificity for discovery of asthma genes and epistasis.

Delivery mode and gut microbial changes correlate with an increased risk of childhood asthma.

There have been reports of associations between cesarean section delivery and the risk of childhood asthma, potentially mediated through changes in the gut microbiota. We followed 700 children in the Copenhagen Prospective Studies on Asthma in Childhood2010 (COPSAC2010) cohort prospectively from birth. We examined the effects of cesarean section delivery on gut microbial composition by 16S rRNA gene amplicon sequencing during the first year of life. We then explored whether gut microbial perturbations due to delivery mode were associated with a risk of developing asthma in the first 6 years of life. Delivery by cesarean section was accompanied by marked changes in gut microbiota composition at one week and one month of age, but by one year of age only minor differences persisted compared to vaginal delivery. Increased asthma risk was found in children born by cesarean section only if their gut microbiota composition at 1 year of age still retained a cesarean section microbial signature, suggesting that appropriate maturation of the gut microbiota could mitigate against the increased asthma risk associated with gut microbial changes due to cesarean section delivery.

Delayed Motor Milestones Achievement in Infancy Associates with Perturbations of Amino Acids and Lipid Metabolic Pathways.

The relationship between developmental milestone achievement in infancy and later cognitive function and mental health is well established, but underlying biochemical mechanisms are poorly described. Our study aims to discover pathways connected to motor milestone achievement during infancy by using untargeted plasma metabolomic profiles from 571 six-month-old children in connection with age of motor milestones achievement (Denver Developmental Index) in the Copenhagen Prospective Studies on Asthma in Childhood 2010 (COPSAC2010) mother–child cohort. We used univariate regression models and multivariate modelling (Partial Least Squares Discriminant Analysis: PLS-DA) to examine the associations and the VDAART (Vitamin D Antenatal Asthma Reduction Trial) cohort for validation. The univariate analyses showed 62 metabolites associated with gross-motor milestone achievement (p < 0.05) as well as the PLS-DA significantly differentiated between slow and fast milestone achievers (AUC = 0.87, p = 0.01). Higher levels of tyramine-O-sulfate in the tyrosine pathway were found in the late achievers in COPSAC (p = 0.0002) and in VDAART (p = 0.02). Furthermore, we observed that slow achievers were characterized by higher levels of fatty acids and products of fatty acids metabolism including acyl carnitines. Finally, we also observed changes in the lysine, histidine, glutamate, creatine and tryptophan pathways. Observing these metabolic changes in relation to gross-motor milestones in the first year of life, may be of importance for later cognitive function and mental health.

Early life bacterial airway colonization, local immune mediator response and risk of otitis media

Introduction. Acute otitis media (AOM) is the most common bacterial infection in early childhood, but the underlying mechanisms making some children more susceptible are poorly understood.Aim. To examine the associations between bacterial airway colonization in early life and the risk of AOM and tympanostomy tube insertion (TTI), and whether such associations are modulated by an insufficient local immune mediator response to bacterial colonization.Methodology. Bacterial cultures from hypopharyngeal samples were obtained at 1 week, 1 month and 3 months of age in the Copenhagen Prospective Studies on Asthma in Childhood 2010 (COPSAC2010) cohort comprising 700 children. Twenty immune mediators were quantified from airway mucosal lining fluid sampled at 1 month. AOM symptoms were registered in a daily diary until 3 years. Information on TTI in the first 3 years was obtained from national registers.Results. Children colonized with Streptococcus pneumoniae at 1 month of age had increased incidence of AOM [aIRR 2.43 (1.14-5.21)] and children colonized with Moraxella catarrhalis at 1 month or Haemophilus influenzae at 3 months had an increased risk of TTI [aHR 1.45 (1.00-2.10) and 1.73 (1.10-2.71)]. There were no associations between the local immune mediator response to colonization and risk of AOM or TTI.Conclusion. Pathogenic bacterial airway colonization in early life was found to be associated with an increased risk of otitis media, albeit not consistently. These associations were independent of the local immune response to colonization.

Antibiotic exposure in infancy and development of BMI and body composition in childhood

BackgroundIt has been hypothesized that antibiotic usage in early life could contribute to development of overweight in childhood. Studies have seen association between antibiotic usage and overweight in childhood. We aimed to investigate the relationship between antibiotic exposure in infancy and development of body mass index (BMI) and body composition. MethodsA prospective mother–child cohort study of 738 pregnant women and their 700 children, Copenhagen Prospective Studies on Asthma in Childhood2010 (COPSAC2010). Information on antibiotic exposure was collected by interviews. Height/length and weight measures were collected at age 1, 2, 3, 4, 5 and 6 years and body composition was determined by a dual-energy X-ray absorptiometry (DXA) scan at age 3.5 and 6 years. Findings306 (46%) of the 661 children were exposed to antibiotics before 1 year of age. There were no differences in BMI z-score development at age 1–6 years between children exposed to antibiotics compared to unexposed: z-score difference, –0.06 (95%CI: –0.17;0.06), p = 0.33, and no sex-differences (p-interaction = 0.48). Children exposed vs. not exposed to antibiotics had comparable fat percentage at 6 years of age: log(mean difference), 0.60% (95%CI: −0.212 to 1.41), p = 0.15. InterpretationChildren exposed to antibiotics had similar BMI, BMI z-score and body composition between 1 and 6 years of life compared to unexposed children. Our study does not support the hypothesis that antibiotic exposure in infancy leads to development of obesity in the first 6 years of life. FundingThe Lundbeck Foundation, The Ministry of Health, Danish Council for Strategic Research and The Capital Region Research Foundation.

Children with Asthma Have Fixed Airway Obstruction through Childhood Unaffected by Exacerbations

Children with asthma may have a disease course with or without exacerbations, but the relationship between exacerbations and lung function development is poorly understood. To compare lung function trajectories from birth till adolescence in asthmatic children with and without exacerbations. Children with asthma from the Copenhagen Prospective Studies on Asthma in Childhood2000 (COPSAC2000) birth cohort had lung function and bronchial reactivity assessed repeatedly from 1 month to 13 years. Exacerbations were diagnosed at the COPSAC clinic defined as symptoms requiring hospitalization, oral or high-dose inhaled corticosteroid treatment. Mixed models were applied to analyze lung function trajectories. Children with asthma with exacerbations (N= 50) had a trajectory of increased, fixed airway obstruction compared with children without exacerbations (N= 47): z-score difference in airway resistance (sRawz) (95% confidence interval [CI]):+0.34 (+0.03;+0.66), P= .03, and maximal mid-expiratory flow (MMEFz):-0.41 (-0.69;-0.13), P= .004, but no differences in forced expiratory volume (FEVz):-0.14 (-0.41;+0.13), P= .29, or bronchial reactivity to methacholine (PDz):+0.08 (-0.26;+0.42), P= .65. This did not change comparing lung function trajectories before and after exacerbations: z-score difference (95% CI) sRawz:-0.04 (-0.35; 0.27), P= .80; MMEFz: 0.01 (-0.02; 0.04), P= .55; FEVz: 0.02 (-0.02; 0.05), P= .42; and PDz:-0.01 (-0.06; 0.05), P= .88. Children with asthma with exacerbations compared with children with asthma without exacerbations are characterized by increased airway obstruction since infancy through childhood. The airway obstruction is a fixed trajectory without progression due to exacerbations, suggesting that exacerbations are a consequence rather than a cause of diminished airway caliber in childhood.

Infant airway microbiota and topical immune perturbations in the origins of childhood asthma

Asthma is believed to arise through early life aberrant immune development in response to environmental exposures that may influence the airway microbiota. Here, we examine the airway microbiota during the first three months of life by 16S rRNA gene amplicon sequencing in the population-based Copenhagen Prospective Studies on Asthma in Childhood 2010 (COPSAC2010) cohort consisting of 700 children monitored for the development of asthma since birth. Microbial diversity and the relative abundances of Veillonella and Prevotella in the airways at age one month are associated with asthma by age 6 years, both individually and with additional taxa in a multivariable model. Higher relative abundance of these bacteria is furthermore associated with an airway immune profile dominated by reduced TNF-α and IL-1β and increased CCL2 and CCL17, which itself is an independent predictor for asthma. These findings suggest a mechanism of microbiota-immune interactions in early infancy that predisposes to childhood asthma.

The role of the 17q21 genotype in the prevention of early childhood asthma and recurrent wheeze by vitamin D.

Evidence suggests vitamin D has preventive potential in asthma; however, not all children benefit from this intervention. This study aimed to investigate whether variation in the functional 17q21 single nucleotide polymorphism rs12936231 affects the preventive potential of vitamin D against asthma.A combined secondary analysis of two randomised controlled trials of prenatal vitamin D supplementation for the prevention of asthma in offspring (Vitamin D Antenatal Asthma Reduction Trial (VDAART) and Copenhagen Prospective Studies on Asthma in Childhood 2010 (COPSAC2010)) was performed, stratifying by genotype and integrating metabolite data to explore underlying mechanisms.The protective effect of vitamin D on asthma/wheeze was evident among children with the low-risk rs12936231 GG genotype (hazard ratio (HR) 0.49, 95% CI 0.26-0.94, p=0.032) but not the high-risk CC genotype (HR 1.08, 95% CI 0.69-1.69, p=0.751). In VDAART, in the GG genotype vitamin D supplementation was associated with increased plasma levels of sphingolipids, including sphingosine-1-phosphate (β 0.022, 95% CI 0.001-0.044, p=0.038), but this was not evident with the CC genotype, known to be associated with increased expression of ORMDL3 in bronchial epithelial cells. Sphingolipid levels were associated with decreased risk of asthma/wheeze, and there was evidence of interactions between sphingolipid levels, vitamin D and genotype (p-interactionvitaminD*genotype*sphingosine-1-phosphate=0.035). In a cellular model, there was a significant difference in the induction of sphingosine-1-phosphate by vitamin D between a control human bronchial epithelial cell line and a cell line overexpressing ORMDL3 (p=0.002).Results suggest prenatal vitamin D supplementation may reduce the risk of early childhood asthma/wheeze via alterations of sphingolipid metabolism dependent on the 17q21 genotype.