Vitamin D concentrations were often insufficient among native Norwegian adolescents and children with a non-Western immigrant background.

AIM: The aim of this study was to review papers that assessed the vitamin D intake of children living in Norway, as research has suggested that it has remained below the recommended daily allowance of 10 µg/day. METHODS: This mini review examined the vitamin D status of Norwegian children aged 0-18 years by systematically searching the PubMed, Google Scholar and Scopus databases from 1 January 2009 to 1 July 2020. RESULTS: The review comprised six studies published in English between 2009 and 2020 on native-born and non-Western immigrant children. Most studies defined satisfactory vitamin D status as a plasma 25-hydroxyvitamin D (25(OH)D) concentration of 50 nmol/L, with 25-50 nmol/L being classified as insufficient and below 25 nmol/L being classified as deficient. A study of healthy children found that 21% had insufficient levels and a further 1% were deficient, but this second finding was only among adolescents. Other studies showed that 47% of Norwegian children with a non-Western immigrant background were deficient, and so were 19% of overweight children, mainly adolescents. CONCLUSION: Vitamin D concentrations were often insufficient among children living in Norway, particularly adolescents and those with a non-Western immigrant background. Higher recommended supplements may be needed.

Basic benefit in the case of non-coeliac gluten sensitivity. / Grunnstønad ved glutenintoleranse uten cøliaki.

Studies show that there is reason to be sceptical about the significance of gluten in non-coeliac gluten sensitivity. It is now time to evaluate the right of patients with such symptoms to basic benefit.

Food intolerance in children. / Matintoleranse hos barn.

A variety of factors can cause food intolerance, and the symptoms span a wide range. It is likely that food intolerance in children is overdiagnosed.

Lung function at 10 yrs is not improved by early corticosteroid treatment in asthmatic children.

Early intervention with inhaled corticosteroid (ICS) treatment for lung function development in childhood is debated. In view of lung function at birth, we aimed to assess if early use of ICS influenced lung function at 10 yrs of age. A 10-yr follow-up study of 614/802 children (mean age 10.9 +/- 0.9 yrs) with lung function measurements at birth in the Environment and Childhood Asthma study in Oslo included information on ICS treatment (124 with history of asthma) obtained at 2 and 10 yrs by parental interviews. Main outcomes at 10 yrs were the best values (% predicted and Z-scores) of forced expiratory volume in 1 s (FEV(1)) and mid-expiratory flow. The main explanatory factors were never, past or current use of ICS and Z-scores of the tidal flow-volume ratio t(PTEF)/t(E) [time to peak expiratory flow (t(PTEF)) and total expiratory time (t(E))] at birth. ICS treatment, reported by 11.9% of children in the population sample and 71.6% with current asthma, did not significantly influence lung function from birth to 10 yrs. The best values (and Z-scores) of FEV(1), and mid-expiratory flow were similar (p > 0.1) in subjects receiving ICS during and after 0-3 yrs of age, after 3 yrs only or currently compared with steroid naïve children. Almost half of the change in lung function 0-10 yrs was explained by gender, a history of asthma and t(PTEF)/t(E) at birth. ICS treatment for asthma, reported in every eighth child by age 10 yrs, did not significantly improve lung function from birth to 10 yrs.

Lung function at 10 yr is not impaired by early childhood lower respiratory tract infections.

The causal relationship between lower respiratory tract infections (LRIs) in early life and reduced lung function later in childhood is unsettled. Therefore, we assessed whether LRIs the first 2 yr of life influenced lung function development from birth to school age. In the prospective Oslo birth cohort, 'the Environment and Childhood Asthma (ECA) study' lung function was measured at birth in 802 infants by tidal flow volume loops and in 664 infants by passive respiratory mechanics and half yearly questionnaires, including LRI questions, were completed until 2 yr of age. The present study includes 607 children with information about LRIs the first 2 yr of life and successfully forced expiratory flow (FEF) volume measurements at the 10-yr follow-up assessment. At 10 yr of age, FEF at 50% of forced vital capacity (FEF(50)) (mean 95% confidence interval) was reduced in children with at least one bronchiolitis (85.0, 80.6-89.5, p = 0.020) or bronchitis (86.2, 82.6-89.8, p = 0.030) or > or =3 LRIs (83.4, 78.1-88.8, p = 0.017) when compared with no LRIs (90.6, 88.8-92.5) by 2 yr of life. The effects were significant in girls only when stratifying for gender. Among girls with later bronchiolitis compliance of the respiratory system (3.64, 3.17-4.10 vs. 4.18, 3.98-4.37, p = 0.031) and the ratio of time to peak tidal expiratory flow to total expiratory time (t(PTEF)/t(E)) measured at birth was significantly reduced (0. 26, 0.23-0.29 vs. 0.32, 0.30-0.33, p = 0.005) when compared with children with no LRIs. Change in lung function from birth (by t(PTEF)/t(E)) to 10 yr of age was not significantly associated with LRIs the first 2 yr of life, and LRIs by 2 yr of life were not significantly associated with lung function at 10 yr of age in regression analyses including lung function at birth and other possible predictors of lung function at 10 yr. In our study, LRIs during the first 2 yr of life did not impair lung function development from birth until 10 yr of age.

T cell-specific T-box transcription factor haplotype is associated with allergic asthma in children.

BACKGROUND: T cell-specific T-box transcription factor (T-bet) is a member of the T-box family of transcription factors regulating lineage commitment of T(H) lymphocytes toward a predominant T(H)1 phenotype. Asthma and allergy are common complex diseases characterized by T(H)2-mediated inflammation. OBJECTIVE: We aimed to assess possible relationships between the T-bet gene (TBX21) and asthma and allergy in children. METHOD: Twelve single nucleotide polymorphisms (SNPs) in the TBX21 region were genotyped in 948 children from the Environment and Childhood Asthma study. Allele and haplotype frequencies were compared in children with and without asthma (by 10 years) and allergy (> or =1 positive skin prick test response), as well as for the quantitative traits bronchial hyperresponsiveness determined by means of methacholine bronchial challenge testing, lung function determined by means of forced flow volume loops, fractional exhaled nitric oxide measurement, eosinophil count, and serum total IgE level. RESULTS: Allergic asthma was significantly associated with 2 of the tested SNPs (rs11650354 and rs16947078) and further associated with the particular haplotype including these SNPs, with homozygote status resulting in an odds ratio of 8.3 (95% CI, 2.5-26.9) for allergic asthma. Neither nonallergic asthma or "allergy alone" nor the remaining quantitative variables were associated with TBX21 SNPs or haplotypes. CONCLUSION: An association between a specific TBX21 haplotype and allergic asthma in children is demonstrated for the first time and might explain previously detected associations between SNPs within TBX21 and asthma and bronchial hyperresponsiveness.

Inhaled corticosteroids in children: use and effects of early treatment on asthma and lung function. Prevalence of asthma and the impact of severity in early life on later asthma in childhood.

INTRODUCTION: The role of inhaled corticosteroids (ICS) on disease progression in asthmatic children is not yet clear. AIMS: This study was conducted (i) to determine how often ICS were used for treatment of obstructive airways disease (OAD) in early childhood; (ii) to assess if ICS treatment had an effect on lung function in young children with recurrent bronchial obstruction (rBO); (iii) to explore if early ICS treatment in children with OAD during the first 2 years of life can modify occurrence of current asthma in school children; (iv) to define a severity score for severity of OAD during the first 2 years of life and assess if the severity score can be used to predict asthma in school children; and (v) to investigate the prevalence of asthma in children in an urban population. SUBJECTS AND METHODS: The present study is part of a 10-year follow-up of children in the prospective birth cohort (n = 3754), the Environment and Childhood Asthma study in Oslo. For aim 1, all children from the entire cohort who had completed follow-up questionnaires as well as all children defined with rBO were assessed. For aim 2, 54 children with rBO (with and without ICS treatment) and 15 controls with tidal flow volume measurements upon presentation of the disease and 2 years of age were studied. For aims 3 and 4, 459 subjects (with and without rBO at 2 years of age) from the case control study who attended 10-year follow-up were studied. For aim 5, the 616 of 803 subjects who had lung function measurements performed after birth were reinvestigated at the age of 10 years. RESULTS: A total of 2.1% of all the children in the cohort and 21% of children with rBO had received ICS treatment by 2 years of age. The mean difference of change in baseline tidal breathing (the ratio of time to peak expiratory flow to total expiratory time) was significantly higher in the ICS-treated group only by 2 years of age and correlated significantly with duration of ICS treatment. However, in rBO children, the use of ICS treatment before 2 years of age was not associated with reduced risk of current asthma at 10 years of age. The risk (odds ratio, 95% confidence interval) of current asthma among rBO subjects with a severity score above five was 20.2, 9.9-41.3 compared to controls. In 10-year-old children, the lifetime prevalence of asthma was 20.2%. CONCLUSIONS: One-fifth of young children with recurrent bronchial obstruction had received inhaled corticosteroids by age 2 years. Lung function appeared to improve in children using ICS from the start of symptoms of OAD until 2 years of age, mostly in children with the longest duration of treatment. However, use of ICS during the first 2 years of life in children with OAD did not reduce asthma present 8 years later. A scoring system based on severity and frequency of OAD during the first 2 years of life predicted current asthma at 10 years of age. One in five 10-year-old children in the city of Oslo at some time had asthma.

Lung function development in the first 2 yr of life is independent of allergic diseases by 2 yr.

The aim of the study was to assess if lung function at birth predicts lung function at 2 yr and secondly, if lung function development was influenced by the common phenotypes of recurrent bronchial obstruction (rBO) or atopic eczema (AE) by 2 yr. Lung function was assessed at birth (n = 802) and at 2 yr within the prospective birth cohort study 'the Environment and Childhood Asthma Study' in Oslo. The 135 children with lung function measured at birth by tidal flow volume (TFV) loops and passive respiratory mechanics, who were included in a nested case-control study were reinvestigated at 2 yr with clinical examination, TFV loops (n = 90) (mean age 26.6 (3.7 s.d.) months), skin prick test and parental interview. Children were categorized into quartiles (lower, middle two, upper) according to time to peak tidal expiratory flow/total expiratory time (t(PTEF)/t(E)) at birth as well as clinical phenotype based on the presence of rBO and/or AE (ever) by 2 yr. The observed reduction in mean t(PTEF)/t(E) from birth to 2 yr within the quartiles, were not significantly different after controlling for 'regression to the mean'. t(PTEF)/t(E) at birth correlated significantly with t(PTEF)/t(E) at 2 yr, (r = 0.475, p < 0.001). Children with both rBO and AE by 2 yr had significantly lower t(PTEF)/t(E) at 2 yr (p = 0.002) and at birth (p = 0.027), compared with children with no rBO or AE. Clinical phenotype at 2 yr did not influence the change in t(PTEF)/t(E) from birth to 2 yr. This study demonstrates a clear tracking of lung function from birth, not influenced by rBO or AE by 2 yr.

No evidence that early use of inhaled corticosteroids reduces current asthma at 10 years of age.

BACKGROUND: It is debated whether early treatment with inhaled corticosteroids (ICS) can change the natural course of childhood asthma. AIM: To assess if ICS treatment before 2 years of age in children with obstructive airways disease reduces current asthma at 10 years of age. METHODS: Children with (n=233) and without (n=219) recurrent (r) bronchial obstruction (BO) attending clinical examination at 2 years of age in the birth cohort Environment and Childhood Asthma study in Oslo, were reinvestigated at 10 years of age. Current asthma (CA) at 10 years was defined as asthma with either symptoms and/or asthma treatment during the last year, and/or 10% fall in forced expired volume in 1s after standardized treadmill run. The risk of CA was assessed by logistic regression and propensity modelling (including gender, parental atopy and severity score at 2 years) in children with rBO who received ICS or not by 2 years. RESULTS: CA was found in 97 children, more often among rBO children with (56.9%) and without ICS treatment (30.8%) compared to no-BO children (5.5%) (p<0.001). In rBO children logistic regression analyses (adjusted odds ratio aOR (95% confidence interval)) identified male gender (aOR 1.82 (1.01-3.27), p=0.046) and severity score at 2 years 1.14 (1.03-1.28), (p=0.01), as significant and ICS treatment as non-significant 2.00 (0.98-4.12) risk factors for CA. With propensity modelling adjusting for disease severity, ICS treatment by 2 years caused a non-significant increased risk aOR of CA of 1.84 (0.89-3.82). CONCLUSION: No evidence was found that early use of ICS before age two in children with rBO reduces current asthma 8 years later.

Reduced lung function at birth and the risk of asthma at 10 years of age.

BACKGROUND: Reduced lung function in early infancy has been associated with later obstructive airway diseases. We assessed whether reduced lung function shortly after birth predicts asthma 10 years later. METHODS: We conducted a prospective birth cohort study of healthy infants in which we measured lung function shortly after birth with the use of tidal breathing flow-volume loops (the fraction of expiratory time to peak tidal expiratory flow to total expiratory time [t(PTEF)/t(E)]) in 802 infants and passive respiratory mechanics, including respiratory-system compliance, in 664 infants. At 10 years of age, 616 children (77%) were reassessed by measuring lung function, exercise-induced bronchoconstriction, and bronchial hyperresponsiveness (by means of a methacholine challenge) and by conducting a structured interview to determine whether there was a history of asthma or current asthma. RESULTS: As compared with children whose t(PTEF)/t(E) shortly after birth was above the median, children whose t(PTEF)/t(E) was at or below the median were more likely at 10 years of age to have a history of asthma (24.3% vs. 16.2%, P=0.01), to have current asthma (14.6% vs. 7.5%, P=0.005), and to have severe bronchial hyperresponsiveness, defined as a methacholine dose of less than 1.0 micromol causing a 20% fall in the forced expiratory volume in 1 second (FEV1) (9.1% vs. 4.9%, P=0.05). As compared with children whose respiratory-system compliance was above the median, children with respiratory compliance at or below the median more often had a history of asthma (27.4% vs. 14.8%; P=0.001) and current asthma (15.0% vs. 7.7%, P=0.009), although this measure was not associated with later measurements of lung function. At 10 years of age, t(PTEF)/t(E) at birth correlated weakly with the maximal midexpiratory flow rate (r=0.10, P=0.01) but not with FEV1 or forced vital capacity. CONCLUSIONS: Reduced lung function at birth is associated with an increased risk of asthma by 10 years of age.

CFTR gene mutations and asthma in the Norwegian Environment and Childhood Asthma study.

BACKGROUND: Several candidate genes have been implicated in the etiology of asthma, including the gene coding for the cystic fibrosis transmembrane conductance regulator (CFTR). Mutations in the CFTR gene result in derangements of mucociliary clearance. Homozygotes for CFTR mutations develop cystic fibrosis (CF), a disorder characterized mainly by lung and pancreas disease. OBJECTIVE: To investigate whether there was an increased frequency of CFTR mutations in asthma patients. METHODS: Seven hundred and three subjects aged 10-11 years from the environment and childhood asthma (ECA) study were included in the present study. Possible associations between asthma, reduced lung function, bronchial hyperresponsiveness (BHR), and increased or decreased nitrogen oxide (NO) levels (based on structural parental interview, spirometry, PD20 methacholine challenge test and exhaled NO measurements), and the five most common CFTR mutations in Norway (DeltaF508, R117H, R117C, 4005+2T-->C, 394delTT), the modulating polymorphisms IVS8(TG)mTn and the IVS8-5T were investigated. RESULTS: No association were found between asthma, reduced lung function, BHR or exhaled NO levels and CF heterozygosity. However, the IVS8(TG)11T7 haplotype was associated with normal lung function. CONCLUSIONS: Our results do not support the hypothesis that CFTR mutations or polymorphisms play a role in the pathogenesis of asthma in children. However, the distribution of Tn(TG)m haplotypes differed between individuals with reduced lung function and individuals with normal lung function.