Asthma and allergy in children : an epidemiological study of asthma and allergy in schoolchildren living in Northern Norway and Russia with respect to prevalence trends 1985-1995-2000, geographic differences in prevalence and biomarkers

Abstract

The thesis has focused on asthma, AR and AD in children in a limited geographical region over a limited period of time and has studied the prevalence trends, geographical differences in prevalence and the biomarker s-ECP. These are the main findings in the five papers published: <ul id = «mylist»> <li> The prevalence of asthma and allergy in north Norwegian primary schoolchildren increased substantially between 1985 and 1995. </li> <li> By studying the prevalence trends in 9-11 years old children living in Troms and Finnmark over the period from 1985 to 2000, we found that overall prevalence of AR and prevalence of asthma in boys were continuously increasing. The prevalence of AD levelled from 1995 to 2000 and the prevalence of asthma in girls even showed declining trends over the last five years studied. </li> <li> In all studies that allowed a distinction between Sami and Norse ethnicity, generally a higher prevalence of asthma and allergy was found among children defined as Sami. </li> <li> Russian children on the Kola Peninsula have less asthma and allergy compared to their Norwegian neighbours. However, a high prevalence of respiratory symptoms in these children may represent undiagnosed, non-allergic asthma. </li> <li> In an unselected children population (similar to the population of children encountered in general practice) the occurrence of AD or AR was not reflected by an increased s-ECP level. Despite elevated serum levels in children with asthma, less than 20% of the children with high s-ECP values had asthma. We concluded that the associations between s-ECP and asthma and allergy are weak in an unselected population of children. </li></ul>