Environmental peanut exposure increases the risk of peanut sensitization in high-risk children.

BACKGROUND: High household peanut consumption is associated with the development of peanut allergy, especially when peanut allergic cases are compared against atopic controls; thus, environmental peanut exposure (EPE) may be a risk factor for peanut sensitization and allergy. In this study, we explored the relationship between EPE and school-age peanut sensitization in a population-based cohort. METHODS: Maternal bed dust was collected postnatally, and EPE was quantified using a polyclonal peanut ELISA. Peanut sensitization was assessed by specific IgE to peanut extract and sIgE to peanut protein component allergens Ara h 1, 2 or 3 ≥ 0.35kU/L (primary peanut sensitization). Initial nested case-control analysis was performed comparing peanut-sensitized cases against high-risk controls (matched for parental atopy) (n = 411) using a conditional regression analysis. This was followed by whole cohort analysis (n = 1878) comparing EPE against peanut sIgE sensitization at ages 4 and 8 years using generalized estimating equations and against primary peanut sensitization at age 8 years using a logistic regression model. Finally, a subgroup analysis was performed comparing the impact of EPE in peanut-sensitized vs egg-sensitized, peanut-tolerant individuals using logistic regression analysis. Levels of EPE were compared between groups using the Mann-Whitney U test. RESULTS: In the nested case-control analysis, a higher level of EPE around birth was associated with peanut-specific IgE sensitization at age 4 years (OR=1.41, 95% CI:1.05-1.90) and primary peanut sensitization at age 8 years (OR=2.11, 95% CI:1.38-3.22) compared against high-risk controls. When the whole BAMSE cohort was assessed, EPE was no longer associated with peanut sensitization; however, on subgroup analysis, EPE was associated with primary peanut sensitization when compared against egg-sensitized peanut-tolerant controls with an adjusted odds ratio of 1.44 per unit EPE (95% CI:1.06-1.94). There was no significant interaction between EPE and FLG loss-of-function mutations, egg sensitization at age 4 years, infantile eczema or parental atopy on peanut sensitization. CONCLUSIONS: Higher levels of environmental exposure to peanut in the first few months of life appear to increase the probability of developing school-age peanut sensitization in atopic children (based on egg sensitization and parental atopy).

Exposure to organophosphate and polybrominated diphenyl ether flame retardants via indoor dust and childhood asthma.

Although the ubiquitous detection of polybrominated diphenyl ether (PBDE) and organophosphate flame retardants (PFRs) in indoor dust has raised health concerns, only very few epidemiological studies have assessed their impact on human health. Inhalation of dust is one of the exposure routes of FRs, especially in children and can be hazardous for the respiratory health. Moreover, PFRs are structurally similar to organophosphate pesticides, which have been associated with allergic asthma. Thus, we investigated whether the concentrations of PFRs and PBDEs in indoor dust are associated with the development of childhood asthma. We selected 110 children who developed asthma at 4 or at 8 years old and 110 matched controls from a large prospective birth cohort (BAMSE - Barn, Allergy, Milieu Stockholm Epidemiology). We analyzed the concentrations of 7 PFRs and 21 PBDEs in dust collected around 2 months after birth from the mother's mattress. The abundance rank in dust was as follows: TBOEP⪢TPHP>mmp-TMPP>EHDPHP~TDCIPP>TCEP~TCIPP~BDE-209⪢BDE-99>BDE-47>BDE-153>BDE-183>BDE-100. There was no positive association between the FRs in mattress dust and the development of childhood asthma. In contrast, dust collected from mattresses of the mothers of children who would develop asthma contained significant lower levels of TPHP and mmp-TMPP. This study provides data on a wide range of PFRs and PBDEs in dust samples and development of asthma in children.

IgE antibodies in relation to prevalence and multimorbidity of eczema, asthma, and rhinitis from birth to adolescence.

BACKGROUND: Eczema, asthma, and rhinitis affect a large proportion of children, but their prevalence varies with age. IgE antibodies are also common in the pediatric population. However, the links between IgE, disease, and trajectories are unclear. OBJECTIVE: To better understand the links between sensitization and disease, we studied IgE sensitization ever in relation to eczema, asthma, and rhinitis, in children followed up to 16 years of age. METHODS: From the Swedish population-based birth cohort BAMSE, 2607 children were included. Parental reports from six time points between 1 and 16 years were used to identify children with eczema, asthma, and rhinitis. Blood was collected at 4, 8, and 16 years, and sensitization ever was defined as allergen-specific IgE ≥0.35 kUA /l to common food and/or inhalant allergens at any time point. Odds ratios for eczema, asthma, rhinitis, and multimorbidity in relation to sensitization ever were calculated using generalized estimating equations. RESULTS: Fifty-one percent were sensitized at least once up to 16 years. Almost a quarter of ever-sensitized children did not have any disease. After adjustment for potential confounders, sensitization ever was significantly associated with the following: (i) eczema throughout childhood, (ii) multimorbidity of eczema, asthma, and rhinitis from 1 to 16 years (OR for multimorbidity: 5.11, 95% CI: 3.99-6.55), (iii) asthma and rhinitis from 4 to 16 years of age. CONCLUSIONS: Specific IgE is strongly associated with eczema and allergic multimorbidity throughout childhood and with asthma and rhinitis from age 4 years. However, 23% of the children with IgE sensitization do not develop any disease in childhood.

Experiences of living with asthma - a focus group study with adolescents and parents of children with asthma.

OBJECTIVE: The goal for asthma treatment is that every individual, so far as possible, shall live without symptoms and exacerbations. Patients and health care professionals sometimes have different perceptions of what is important for achieving good quality of life. This work aims to describe the experiences among adolescents as well as those of parents with young children living with asthma. METHODS: Four focus group interviews were performed, two with parents of young children and two with adolescents. The data were qualitatively analyzed, using Systematic Text Condensation. RESULT: Three themes relevant to the participants' experiences of living with asthma were presented; strategies, frustrations and expectations. The adolescents wanted to be like their peers and developed their own strategies for self-management of asthma, which included not always taking medication as prescribed. The parents emphasized frustration regarding not being believed, lack of understanding feelings of loneliness, or anxiety. One identified expectation was that the participants wanted to be met with competence and understanding in asthma care from health care professionals. Another expectation expressed among parents was that teachers in nursery and primary schools should have more knowledge and understanding on how to care for children with asthma. CONCLUSION: Living with asthma leads to developing personal strategies in self-management of asthma. Moreover both parents and adolescents had expectations of being met by competent and understanding health care professionals. Developing a partnership between patients and health care professionals could be a successful way to improve the care of patients with asthma.

Development and comorbidity of eczema, asthma and rhinitis to age 12: data from the BAMSE birth cohort.

BACKGROUND: Allergy-related diseases are a public health issue, but knowledge on development and comorbidity among children is scarce. The aim was to study the development of eczema, asthma and rhinitis in relation to sex and parental allergy, in a population-based cohort, during childhood. METHODS: At 1, 2, 4, 8 and 12 years, parental questionnaires were used to obtain data on allergy-related diseases. Complete data for all five follow-up occasions were available from 2916 children. Odds ratios for the risk of any allergy-related disease in relation to heredity and sex were calculated using generalized estimating equations. RESULTS: At 12 years, 58% of the children had had eczema, asthma and/or rhinitis at some time. Disease turnover was high for all three diseases throughout the study. Comorbidity increased with age, and at 12 years, 7.5% of all the children were affected by at least two allergy-related diseases. Parental allergy was associated with increased comorbidity and more persistent disease and increased the risk of having any allergy-related disease (adjusted OR 1.76; 95% CI 1.57-1.97) up to 12 years. Male sex was associated with an increased risk throughout childhood. Boys and girls did not differ in disease persistence, and for comorbidity, the differences were minor. CONCLUSIONS: Allergy-related diseases may affect a majority of children. Eczema, asthma and rhinitis develop dynamically throughout childhood, and allergic comorbidity is common. These findings indicate that allergy-related diseases should be neither seen nor studied as isolated entities.

Peanut oil in vitamin A and D preparations: reactions to skin test and manifestation of symptoms.

The aim of this study was to establish whether there is a link between sensitisation to peanut and exposure to peanut oil in vitamin A and D preparations. Forty-one children with a positive in vivo or in vitro test towards peanut were included. Twenty-one children had consumed vitamins A and D in oil solution, 14 in water solution, and 6 both types. Refined and unrefined peanut oils were obtained and skin prick test extracts were prepared. None of the children exhibited a positive SPT in response to the refined peanut extract. In contrast, 15 children exhibited a positive SPT to the unrefined extract. There was no significant difference in the number of children reacting clinically to peanut exposure who had received vitamins A and D in oil-based or water-based formulations. However, children with clinical allergy to peanut and who had exclusively consumed vitamin A and D in peanut oil, exhibited a greater number of different allergic symptoms upon consumption of peanut compared with clinical allergic children who had consumed the vitamins in water solution or both types (p<0.01). This study indicates that sensitisation to peanut during childhood through consumption of vitamins A and D in oil-based solution seems unlikely, but its consumption may contribute to the development of a wider range of clinical symptoms due to peanut exposure.