Exposure to environmental tobacco smoke and sensitisation in children.
ABSTRACT Exposure to environmental tobacco smoke (ETS) increases the risk of respiratory illness in children but data are inconclusive regarding the risk of IgE sensitisation.
To elucidate whether exposure to smoking prenatally and/or postnatally is related to IgE sensitisation in children at 4 years of age.
As part of a prospective birth cohort study (BAMSE), a total of 4089 families with children answered questionnaires when the child was 2 months, 1, 2 and 4 years old on environmental factors and symptoms of allergic disease. Blood collected at age 4 years from 2614 children was analysed for IgE antibodies to common inhalant and food allergens. Odds ratios (OR) and 95% confidence intervals (CI) were calculated using logistic regression with adjustments for potential confounders.
There was no evident association between maternal smoking during pregnancy and risk of IgE sensitisation. In contrast, a dose-response effect was found for exposure to ETS from parental smoking during the first few months of life and IgE sensitisation. There was an increased risk of sensitisation to inhalant and/or food allergens (OR(adj) 1.28 (95% CI 1.01 to 1.62)) among children exposed to ETS at 2 months of age. The risk appeared particularly elevated for indoor inhalant allergens, such as cat (OR(adj) 1.96 (95% CI 1.28 to 2.99)) and for food allergens (OR(adj) 1.46 (95% CI 1.11 to 1.93)). The IgE sensitising effect of ETS seemed to be confined to infants of parents without allergic diseases and to ETS exposure during early infancy.
Our data indicate that exposure in early infancy to ETS increases the risk of IgE sensitisation to indoor inhalant and food allergens.
- SourceAvailable from: PubMed Central[Show abstract] [Hide abstract]
ABSTRACT: Allergic rhinitis, allergic dermatitis, and food allergy are extremely common diseases, especially among children, and are frequently associated to each other and to asthma. Smoking is a potential risk factor for these conditions, but so far, results from individual studies have been conflicting. The objective of this study was to examine the evidence for an association between active smoking (AS) or passive exposure to secondhand smoke and allergic conditions. We retrieved studies published in any language up to June 30th, 2013 by systematically searching Medline, Embase, the five regional bibliographic databases of the World Health Organization, and ISI-Proceedings databases, by manually examining the references of the original articles and reviews retrieved, and by establishing personal contact with clinical researchers. We included cohort, case-control, and cross-sectional studies reporting odds ratio (OR) or relative risk (RR) estimates and confidence intervals of smoking and allergic conditions, first among the general population and then among children. We retrieved 97 studies on allergic rhinitis, 91 on allergic dermatitis, and eight on food allergy published in 139 different articles. When all studies were analyzed together (showing random effects model results and pooled ORs expressed as RR), allergic rhinitis was not associated with active smoking (pooled RR, 1.02 [95% CI 0.92-1.15]), but was associated with passive smoking (pooled RR 1.10 [95% CI 1.06-1.15]). Allergic dermatitis was associated with both active (pooled RR, 1.21 [95% CI 1.14-1.29]) and passive smoking (pooled RR, 1.07 [95% CI 1.03-1.12]). In children and adolescent, allergic rhinitis was associated with active (pooled RR, 1.40 (95% CI 1.24-1.59) and passive smoking (pooled RR, 1.09 [95% CI 1.04-1.14]). Allergic dermatitis was associated with active (pooled RR, 1.36 [95% CI 1.17-1.46]) and passive smoking (pooled RR, 1.06 [95% CI 1.01-1.11]). Food allergy was associated with SHS (1.43 [1.12-1.83]) when cohort studies only were examined, but not when all studies were combined. The findings are limited by the potential for confounding and bias given that most of the individual studies used a cross-sectional design. Furthermore, the studies showed a high degree of heterogeneity and the exposure and outcome measures were assessed by self-report, which may increase the potential for misclassification. We observed very modest associations between smoking and some allergic diseases among adults. Among children and adolescents, both active and passive exposure to SHS were associated with a modest increased risk for allergic diseases, and passive smoking was associated with an increased risk for food allergy. Additional studies with detailed measurement of exposure and better case definition are needed to further explore the role of smoking in allergic diseases. Please see later in the article for the Editors' Summary.PLoS Medicine 03/2014; 11(3):e1001611. · 15.25 Impact Factor
- [Show abstract] [Hide abstract]
ABSTRACT: AimThis study evaluated risk factors for acute wheeze in preschool children and investigated if subnormal levels of vitamin D were associated with increased risk for acute wheeze, atopy or viral/bacterial respiratory infections.Methods We recruited 130 children with acute wheeze, aged six months to four years, from paediatric emergency departments in Stockholm, Sweden, and 101 age-matched controls with no history of wheeze or sensitisation to airborne allergens. Parents answered standardised questionnaires and blood samples were analysed for specific IgE to airborne and food allergens and levels of 25 hydroxyvitamin D (25(OH)D). Nasopharyngeal virus samples were collected during the emergency department visit in the group of children with wheeze and a subset were also tested for bacteria.ResultsVitamin D insufficiency (25(OH)D <75nmol/L (30 ng/mL) was associated with an odds ratio of 2.7 (95% confidence interval 1.1-6.2) for acute wheeze. However, no association was found between vitamin D insufficiency and atopy, presence of virus or bacteria or recurrent infections. Children older than 24 months were particularly at risk of subnormal vitamin D levels, irrespective of wheezing history.Conclusion Our findings support the hypothesis that subnormal levels of vitamin D are associated with acute wheeze in young children.This article is protected by copyright. All rights reserved.Acta Paediatrica 04/2014; · 1.97 Impact Factor
- [Show abstract] [Hide abstract]
ABSTRACT: A significant number of parents are unaware or unconvinced of the health consequences of passive smoking (PS) in children. Physicians could increase parental awareness by giving personal advice. To evaluate the current practices of three Dutch health professions (paediatricians, youth health care physicians, and family physicians) regarding parental counselling for passive smoking (PS) in children. All physicians (n = 720) representing the three health professions in Limburg, the Netherlands, received an invitation to complete a self-administered electronic questionnaire including questions on their: sex, work experience, personal smoking habits, counselling practices and education regarding PS in children. The response rate was 34%. One tenth (11%) of the responding physicians always addressed PS in children, 32% often, 54% occasionally and 4% reported to never attend to it. The three health professions appeared comparable regarding their frequency of parental counselling for PS in children. Addressing PS was more likely when children had respiratory problems. Lack of time was the most frequently mentioned barrier, being very and somewhat applicable for respectively 14% and 43% of the physicians. One fourth of the responders had received postgraduate education about PS. Additionally, 49% of the responders who did not have any education about PS were interested in receiving it. Physicians working in the paediatric field in Limburg, the Netherlands, could more frequently address PS in children with parents. Lack of time appeared to be the most mentioned barrier and physicians were more likely to counsel parents for PS in children with respiratory complaints/diseases. Finally, a need for more education on parental counselling for PS was expressed.PLoS ONE 01/2014; 9(5):e93220. · 3.73 Impact Factor