Allergic diseases and bronchial hyperreactivity in Estonian children in relation to environmental influences
1998 (English)Doctoral thesis, comprehensive summary (Other academic)
This thesis is based on the cross-sectional and prospective study of Estonian children. The aim of this thesis was to assess the prevalence of allergic diseases and respiratory symptoms in Estonian schoolchildren and in young children, to study environmental risk factors for allergic diseases and repiratory symptoms. The cross-sectional study was a part of an epidemiological study in Northeastern part of Europe of the same age group and using standardised methodology in order to allow meaningful comparisons between the countries. The Estonian study was extended to include more extensive assessment of lung function to assess bronchial hyperreactivity (BHR) in Estonian schoolchildren.
1580 schoolchildren from Tallinn and Tartu participated in a cross-sectional study which included parental questionnaires, skin-prick tests, serial peak-flow measurements, methacholine provocation and exercise challenge tests.
Among 10-12 year-old schoolchildren the prevalence of asthma was lower than in children of similar age in Sweden (2.9% vs 8.1% ). In contrast to the low prevalence of atopic diseases, the frequent respiratory infections were more common among the Estonian schoolchildren than in Sweden. Respiratory symptoms and allergic disorders in Tall inn, compared to Tartu showed a similar tendency as the urban-rural gradient in Sundsvall, Sweden. These findings suggest an influence of air pollutants and other adjuvant factors, as related to urbanisation in both countries. Atopic heredity, current dampness and maternal smoking were significant risk factors for the respiratory symptoms in Estonia. The prevalence of BHR to methacholine was 19% in Tall inn and 32% in Tartu (p<O.OOI). Positive exercise challenge tests were recorded in 6% of the children living in Tallinn and in 18% in Tartu (p<O.OOl). In contrast to the results of studies in Western Europe, most children with BHR were not atopic. BHR was apparently more related to other environmental factors, as paternal smoking, use of gas stoves, but also other lifestyle factors could be related, what were not examined. In onr study methacholine challenge and peak-flow rate variability were related to asthma. There was a poor correlation between the different methods to assess BHR, however.
In prospective study 298 healthy, consecutively born newborn babies werefollowed from birth up to 2 years of age. Skin-prick tests with fresh food allergens and inhaled allergens were carried out at 6, 12, and 24 months of age. Symptoms of allergy were searched by employing questionnaires at 3, 6, 9, 12 and 24 months of age.
The prevalence of allergic diseases .increased from 8% at 6 months to 17% at 24 months. The cumulative incidence of allergy was 25%, and atopic dermatitis was the main manifestation of atopy with a peak prevalence of 15% at 2 years of life. Asthma was present in 4 children and allergic rhinoconjunctivitis in 2 children at 2 years. The results of our prospective study showed that prevalence of allergy among Estonian young children was not as low as would be expected. This could possibly indicate that 'western lifestyle' has already affected the infant population born in 1993/94.
Place, publisher, year, edition, pages
Linköping: Linköpings universitet , 1998. , 80 p.
Linköping University Medical Dissertations, ISSN 0345-0082 ; 559
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:liu:diva-28648Local ID: 13804ISBN: 9985-4-0035-6OAI: oai:DiVA.org:liu-28648DiVA: diva2:249459
1998-05-29, Tartu Universitetets huvudbyggnad, Tartu, Estonia, 12:00 (Swedish)
Juntunen-Backman, Kajsu, DocentJannus-Pruljan, Lii, Professor
Papers, included in the Ph.D. thesis, are not registered and included in the posts from 1999 and backwards.2009-10-092009-10-092012-07-27Bibliographically approved