Geir Håland

Asthma in every fifth child in Oslo, Norway: a 10‐year follow up of a birth cohort study*

Background:  The western worlds increase in childhood asthma is suggested to level off. We aimed to investigate asthma prevalence in 10‐year‐old children within the prospective birth cohort Environment and Childhood Asthma (ECA) Study in Oslo established in 1992/1993.

Severity of obstructive airways disease by age 2 years predicts asthma at 10 years of age

Background: Predicting school-age asthma from obstructive airways disease (OAD) in early life is difficult, even when parental and children’s atopic manifestations are taken into consideration. Objective: To assess if the severity of OAD in the first 2 years of life predicts asthma at 10 years of age. Methods: From a nested case control study within the Environment and Childhood Asthma study, 233 2-year-old subjects with recurrent (⩾2 episodes) bronchial obstruction (rBO+) and 216 subjects without bronchial obstruction (rBO−) underwent clinical examination, parental interview, treadmill test and metacholine bronchial hyperresponsiveness (BHR) measurement at 10 years. A severity score at 2 years was calculated by frequency, persistence of bronchial obstruction and hospital admissions because of OAD. Main outcomes: Current asthma at 10 years (asthma with symptoms and/or asthma medication during the past year and/or positive treadmill test). Secondary outcome was metacholine BHR at 10 years. Results: Compared with rBO− subjects, adjusted odds ratio (95% CI) of current asthma among rBO+ was 7.9 (4.1, 15.3), and among rBO+ with a severity score of >5, 20.2 (9.9, 41.3). In receiver operated characteristic analysis, positive and negative predictive values demonstrated the applicability and value of the score, with an optimal cut-off at severity score 5. Children with severity score >5 had severe BHR more often (PD20 metacholine <1 μmol) than children with a lower or 0 score (p = 0.0041). Conclusion: Using a simple scoring system, a high severity score of OAD by 2 years of age is a strong risk factor for, and may predict, current asthma at 10 years of age.

Urinary Biomarkers for Phthalates Associated with Asthma in Norwegian Children

Background: High-molecular-weight phthalates in indoor dust have been associated with asthma in children, but few studies have evaluated phthalate biomarkers in association with respiratory outcomes. Objectives: We explored the association between urinary concentrations of phthalate metabolites and current asthma. Methods: In a cross-sectional analysis, 11 metabolites of 8 phthalates [including four metabolites of di(2-ethylhexyl) phthalate] were measured in one first morning void collected from 2001 through 2004 from 623 10-year-old Norwegian children. Logistic regression models controlling for urine specific gravity, sex, parental asthma, and income were used to estimate associations between current asthma and phthalate metabolite concentrations by quartiles or as log10-transformed variables. Results: Current asthma was associated with both mono(carboxyoctyl) phthalate (MCOP) and mono(carboxynonyl) phthalate (MCNP), although the association was limited to those in the highest quartile of these chemicals. The adjusted odds ratio (aOR) for current asthma was 1.9 (95% CI: 1.0, 3.3) for the highest MCOP quartile compared with the lowest quartile, and 1.3 (95% CI: 0.98, 1.7) for an interquartile-range increase. The aOR for current asthma was 2.2 (95% CI: 1.2, 4.0) for the highest MCNP quartile and 1.3 (95% CI: 1.0, 1.7) for an interquartile-range increase. The other phthalate metabolites were not associated with current asthma. Conclusions: Current asthma was associated with the highest quartiles of MCOP and MCNP, metabolites of two high molecular weight phthalates, diisononyl phthalate and diisodecyl phthalate, respectively. Given the short biological half-life of the phthalates and the cross-sectional design, our findings should be interpreted cautiously.

Paracetamol in early infancy: the risk of childhood allergy and asthma

Aim:  We investigated whether paracetamol exposure in pregnancy and until 6 months of age was associated with allergic disease in school children.

Childhood asthma and early life exposure to indoor allergens, endotoxin and β(1,3)-glucans.

Background Divergent results have been reported regarding early life exposure to indoor environmental agents and the risk of asthma and allergic sensitization later in life.

Diagnostic value of exhaled nitric oxide in childhood asthma and allergy

Sachs‐Olsen C, Lødrup Carlsen KC, Mowinckel P, Håland G, Devulapalli CS, Munthe‐Kaas MC, Carlsen K‐H. Diagnostic value of exhaled nitric oxide in childhood asthma and allergy.
Pediatr Allergy Immunol 2010: 21: e213–e221.
© 2010 John Wiley & Sons A/S

Asthma prediction in school children; the value of combined IgE-antibodies and obstructive airways disease severity score*

To cite this article: Lødrup Carlsen KC, Söderström L, Mowinckel P, Håland G, Pettersen M, Munthe Kaas MC, Devulapalli CS, Buchmann M, Ahlstedt S, Carlsen K‐H. Asthma prediction in school children; the value of combined IgE‐antibodies and obstructive airways disease severity score. Allergy 2010; 65: 1134–1140.

HLA Dr‐Dq haplotypes and the TNFA‐308 polymorphism: associations with asthma and allergy

Background:  The HLA (human leukocyte antigen) class II genes DQB1 and DRB1 and the Tumor Necrosis Factor α gene (TNFA) within the HLA complex (chromosome 6p21) have been associated with asthma and allergy. Due to the strong linkage disequilibrium characterizing this complex and the multiple asthma/allergy expressions, we aimed to determine which of these genes were primarily involved in specific asthma/allergy traits.

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 (FEF50) (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 ≥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 (tPTEF/tE) 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 tPTEF/tE) 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.

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 (tPTEF/tE) 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 tPTEF/tE from birth to 2 yr within the quartiles, were not significantly different after controlling for ‘regression to the mean’. tPTEF/tE at birth correlated significantly with tPTEF/tE at 2 yr, (r = 0.475, p < 0.001). Children with both rBO and AE by 2 yr had significantly lower tPTEF/tE 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 tPTEF/tE 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.