| 11. |
- Bråbäck, Lennart, et al.
(författare)
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Atopic sensitization and respiratory symptoms among Polish and Swedish school children
- 1994
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Ingår i: Clinical and experimental allergy : journal of the British Society for Allergy and Clinical Immunology. - 0954-7894. ; 24:9, s. 826-835
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Tidskriftsartikel (refereegranskat)abstract
- Allergic sensitization and symptoms from the airways in relation to air pollution were compared in 10-12-year-old school children (n = 1113) from urban Konin in central Poland and both urban and rural parts of Sundsvall in northern Sweden. The measurements included parental questionnaires, skin-prick tests and serial peak flow measurements during 2 weeks with simultaneous monitoring of outdoor air pollutants. The skin-prick test technique was validated by IgE antibody determinations. The levels of common industrial pollutants, SO2 and smoke particles were much higher in Konin than in urban Sundsvall and the levels of NO2 were similar. Various respiratory symptoms were more often reported among school children in Konin (except for wheezing and diagnosed asthma). Multiple logistic regression analyses yielded the following increased odds ratios for children in Konin as compared with the reference group (rural Sundsvall): chest tightness and breathlessness 3.48 (95% confidence interval 2.08-5.82), exercise-induced coughing attacks 3.69 (95% confidence interval 1.68-8.10), recurrent episodes of common cold 2.79 (95% confidence interval 1.53-5.09) and prolonged cough 4.89 (95% confidence interval 2.59-9.23). In contrast, as compared with rural Sundsvall, the adjusted odds ratio for a positive skin-prick test was decreased in Konin, but increased in urban Sundsvall, 0.58 (95% confidence interval 0.37-0.91) and 1.67 (95% confidence interval 1.15-2.42) respectively. The study confirms that living in urban, as compared with rural areas, is associated with an increased prevalence of respiratory symptoms and sensitization to allergens. These differences could be explained by air pollution. Respiratory symptoms were more common in a similar urban group of Polish children who were exposed to even higher levels of air pollution. These children, however, had a much lower prevalence of sensitization to allergens, as compared with the Swedish children. This indicates that differences in lifestyle and standard of living between western Europe and a former socialist country influences the prevalence of atopy.
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| 12. |
- Bråbäck, Lennart, et al.
(författare)
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Atopy among schoolchildren in northern and southern Sweden in relation to pet ownership and early life events
- 2001
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Ingår i: Pediatric Allergy and Immunology. - : Wiley. - 0905-6157 .- 1399-3038. ; 12:1
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Tidskriftsartikel (refereegranskat)abstract
- Studies have suggested a higher prevalence of asthma and allergies in northern, as compared to southern. Scandinavia. The aim of this study was to evaluate regional differences in atopy in relation to pet ownership and certain early life events among schoolchildren. (n=2108) aged 10-11 years from Link÷ping in southern Sweden and ╓stersund in northern Sweden. The parents completed a questionnaire, comprising questions on home environment, heredity, socio-economic conditions, and the core questions on symptoms from the International Study of Asthma and Allergies in Childhood. The children were skin-prick tested to eight common inhalant allergens. Information on maternal smoking habits, gestational age, and anthropometric measures were obtained from the Swedish Medical Birth Registry. The prevalence of atopic symptoms and sensitization to pollen were similar in ╓stersund and in Link÷ping. A higher prevalence of sensitization to animal dander among children in ╓stersund could be linked to a higher occurrence of pets in the community. Current cat ownership was related to less sensitivity to cat allergen but only in children with an atopic heredity. Ponderal index >30 kg/m3 was related to an increased risk of atopic sensitization, both in Link÷ping (adjusted odds ratio 2.1, 95% confidence interval 1.1-4.0) and in ╓stersund (adjusted odds ratio 2.0, 95% confidence interval 1.1-3.5). Maternal smoking during pregnancy was related to an increased risk of atopic sensitization among children in Link÷ping, whereas current smoking was associated with a decreased risk of sensitization in -stersund. In conclusion, we demonstrated that a high occurrence of pets in the community was associated with sensitization, whereas atopic symptoms were essentially unaffected. This study has also suggested an association between body size at birth and atopic sensitization at 10-11 years of age.
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| 13. |
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| 14. |
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| 15. |
- Bråbäck, Lennart, et al.
(författare)
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Childhood asthma and smoking exposures before conception - a three-generational cohort study.
- 2018
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Ingår i: Pediatric Allergy and Immunology. - : Wiley. - 0905-6157 .- 1399-3038. ; 29:4, s. 361-368
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Some human and animal studies have recently shown that maternal grandmother's smoking during pregnancy increases the risk of asthma in the grandchildren. We have investigated whether sex of the exposed parent and/or grandchild modifies the association between grandmaternal smoking and grandchild asthma.METHODS: We formed a cohort study based on linkage of national registries with prospectively collected data over three generations. Smoking habits in early pregnancy were registered since 1982 and purchases of prescribed medication since 2005. In all, 10329 children born since 2005 had information on maternal and grandmaternal smoking on both sides and were followed from birth up to 6 years of age. Ages when medication was purchased were used to classify the cohort into never, early transient (0-3 years), early persistent (0-3 and 4-6 years) and late-onset (4-6 years) phenotypes of childhood asthma.RESULTS: Maternal grandmother's smoking was associated with an increased odds of early persistent asthma after adjustment for maternal smoking and other confounders (odds ratio 1.29, 95% confidence interval 1.10-1.51). Grandchild sex did not modify the association. Paternal grandmother's smoking was not associated with any of the asthma phenotypes.CONCLUSION: Maternal but not paternal exposure to nicotine before conception was related to an increased risk of early persistent childhood asthma, but not other asthma phenotypes. Our findings are possibly consistent with a sex specific mode of epigenetic transfer.
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| 16. |
- Bråbäck, Lennart, et al.
(författare)
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Confounding with familial determinants affects the association between mode of delivery and childhood asthma medication : a national cohort study
- 2013
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Ingår i: Allergy, Asthma & Clinical Immunology. - : BioMed Central. - 1710-1484 .- 1710-1492. ; 9:1, s. 14-
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Mode of delivery may affect the risk of asthma but the findings have not been consistent and factors shared by siblings may confound the associations in previous studies. METHODS: The association between mode of delivery and dispensed inhaled corticosteroid (ICS) (a marker of asthma) was examined in a register based national cohort (n=199 837). A cohort analysis of all first born children aged 2-5 and 6-9 years was performed. An age-matched sibling-pair analysis was also performed to account for shared genetic and environmental risk factors. RESULTS: Analyses of first-borns demonstrated that elective caesarean section was associated with an increased risk of dispensed ICS in both 2-5 (adjusted odds ratio (aOR)=1.19, 95% confidence interval (CI) 1.09-1.29) and 6-9 (aOR=1.21, 1.09-1.34) age groups. In the sibling-pair analysis, the increased risk associated with elective caesarean section was confirmed in 2-5 year olds (aOR=1.22, 1.05-1.43) but not in 6-9 year olds (aOR=1.06, 0.78-1.44). Emergency caesarean section and vacuum extraction had some association with dispensed ICS in the analyses of first-borns but these associations were not confirmed in the sibling-pair analyses. CONCLUSIONS: Confounding by familial factors affects the association between mode of delivery and dispensed ICS. Despite this confounding, there was some evidence that elective caesarean section contributed to a modestly increased risk of dispensed ICS but only up to five years of age.
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| 17. |
- Bråbäck, Lennart, et al.
(författare)
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Does traffic exhaust contribute to the development of asthma and allergic sensitization in children : findings from recent cohort studies.
- 2009
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Ingår i: Environmental Health. - 1476-069X. ; 8:17, s. 1-11
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this review was to assess the evidence from recent prospective studies that long-term traffic pollution could contribute to the development of asthma-like symptoms and allergic sensitization in children. We have reviewed cohort studies published since 2002 and found in PubMed in Oct 2008. In all, 13 papers based on data from 9 cohorts have evaluated the relationship between traffic exposure and respiratory health. All surveys reported associations with at least some of the studied respiratory symptoms. The outcome varied, however, according to the age of the child. Nevertheless, the consistency in the results indicates that traffic exhaust contributes to the development of respiratory symptoms in healthy children. Potential effects of traffic exhaust on the development of allergic sensitization were only assessed in the four European birth cohorts. Long-term exposure to outdoor air pollutants had no association with sensitization in ten-year-old schoolchildren in Norway. In contrast, German, Dutch and Swedish preschool children had an increased risk of sensitization related to traffic exhaust despite fairly similar levels of outdoor air pollution as in Norway. Traffic-related effects on sensitization could be restricted to individuals with a specific genetic polymorphism. Assessment of gene-environment interactions on sensitization has so far only been carried out in a subgroup of the Swedish birth cohort. Further genetic association studies are required and may identify individuals vulnerable to adverse effects from traffic-related pollutants. Future studies should also evaluate effects of traffic exhaust on the development and long term outcome of different phenotypes of asthma and wheezing symptoms.
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| 18. |
- Bråbäck, Lennart, et al.
(författare)
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Elective cesarean section and childhood asthma
- 2013
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Ingår i: American Journal of Obstetrics and Gynecology. - : Elsevier BV. - 0002-9378 .- 1097-6868. ; 209:5, s. 496-496
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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| 19. |
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| 20. |
- Bråbäck, Lennart, et al.
(författare)
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Migration and asthma medication in international adoptees and immigrant families in Sweden
- 2011
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Ingår i: Clinical and Experimental Allergy. - : Wiley. - 0954-7894 .- 1365-2222. ; 66, s. 571-572
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Tidskriftsartikel (refereegranskat)abstract
- Background Studies of asthma in migrant populations illustrate the effects of environmental changes. Objective In this register study we investigated the importance of exposure to a western lifestyle in different phases of development in Swedish residents with an origin in regions in the world where asthma usually is less prevalent. Methods The study population comprised 24 252 international adoptees, 47 986 foreign-born and 40 971 Swedish-born with foreign-born parents and 1 770 092 Swedish-born residents with Swedish-born parents (age 6-25 years). Purchased prescribed inhaled corticosteroids (ICS) during 2006 were used as an indicator of asthma. Results International adoptees and children born in Sweden by foreign-born parents had three-to fourfold higher rates of asthma medication compared with foreign-born children. The odds ratios (ORs) of asthma medication declined persistently with age at immigration. For adoptees the ORs compared with infant adoptees were 0.78 [95% confidence interval (CI) 0.71-0.85] for those adopted at 1-2 years, 0.51 (0.42-0.61) at 3-4 years and 0.35 (0.27-0.44) after 5 or more years of age. Corresponding ORs for foreign-born children with foreign-born parents immigrating at 0-4 years, at 5-9 years, at 10-14 years and at 15 years or more were 0.73 (0.63-0.86), 0.56 (CI 0.46-0.68) and 0.35 (CI 0.28-0.43), respectively. The ORs were only marginally affected by adjustment for region of birth and socio-economic indicators. Conclusions and Clinical Relevance Age at immigration is a more important determinant of purchased ICS than population of origin. This indicates the importance of environmental factors for asthma in schoolchildren and young adults.
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