Joakim Bunne1, Helena Moberg1, Linnea Hedman2, Martin Andersson1, Anders Bjerg3, Bo Lundbäck4, Eva Rönmark5. 1. Department of Public Health and Clinical Medicine, Division of Occupational and Environmental Medicine, the OLIN Unit, Umeå University, Umeå, Sweden. 2. Department of Public Health and Clinical Medicine, Division of Occupational and Environmental Medicine, the OLIN Unit, Umeå University, Umeå, Sweden; Department of Health Sciences, Division of Nursing, Luleå University of Technology, Luleå, Sweden. 3. Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden. 4. Krefting Research Centre, Institute of Medicine, University of Gothenburg, Gothenburg, Sweden. 5. Department of Public Health and Clinical Medicine, Division of Occupational and Environmental Medicine, the OLIN Unit, Umeå University, Umeå, Sweden. Electronic address: eva.ronmark@nll.se.
Abstract
BACKGROUND: Time trends of incidence of allergic sensitization are unknown and recent trends of prevalence and risk factors are lacking. OBJECTIVE: To estimate the incidence, prevalence, remission, risk factors, and time trends for allergic sensitization among schoolchildren followed from age 7 to 8 years to age 11 to 12 years. METHODS: In 2006, all children in grades 1 and 2 aged 7 to 8 years in 2 municipalities in northern Sweden were invited to a questionnaire survey and to skin prick testing to 10 common airborne allergens. The cohort was reexamined in 2010, with additional blood sampling for specific IgE. Participation rates were 90% (n = 1700) at age 7 to 8 years and 85% (n = 1657) at age 11 to 12 years. The results were compared with a cohort examined by identical methods 10 years earlier. RESULTS: The prevalence of positive skin prick test result to any allergen increased from 30% at age 7 to 8 years to 41% at age 11 to 12 years (P < .001). The cumulative 4-year incidence was 18%, while remission was low. Sensitization to pollen and furred animals was most common. A family history of allergy was significantly associated with incident sensitization, whereas the presence of furred animals at home was negatively associated. The prevalence at age 7 to 8 years and at age 11 to 12 years and the 4-year incidence were all significantly higher compared with the cohort examined 10 years earlier. CONCLUSIONS: The prevalence of allergic sensitization increased by age as a consequence of a high incidence and a low remission. The trends of increasing incidence and prevalence among schoolchildren imply future increases in the prevalence of allergic diseases.
BACKGROUND: Time trends of incidence of allergic sensitization are unknown and recent trends of prevalence and risk factors are lacking. OBJECTIVE: To estimate the incidence, prevalence, remission, risk factors, and time trends for allergic sensitization among schoolchildren followed from age 7 to 8 years to age 11 to 12 years. METHODS: In 2006, all children in grades 1 and 2 aged 7 to 8 years in 2 municipalities in northern Sweden were invited to a questionnaire survey and to skin prick testing to 10 common airborne allergens. The cohort was reexamined in 2010, with additional blood sampling for specific IgE. Participation rates were 90% (n = 1700) at age 7 to 8 years and 85% (n = 1657) at age 11 to 12 years. The results were compared with a cohort examined by identical methods 10 years earlier. RESULTS: The prevalence of positive skin prick test result to any allergen increased from 30% at age 7 to 8 years to 41% at age 11 to 12 years (P < .001). The cumulative 4-year incidence was 18%, while remission was low. Sensitization to pollen and furred animals was most common. A family history of allergy was significantly associated with incident sensitization, whereas the presence of furred animals at home was negatively associated. The prevalence at age 7 to 8 years and at age 11 to 12 years and the 4-year incidence were all significantly higher compared with the cohort examined 10 years earlier. CONCLUSIONS: The prevalence of allergic sensitization increased by age as a consequence of a high incidence and a low remission. The trends of increasing incidence and prevalence among schoolchildren imply future increases in the prevalence of allergic diseases.
Authors: Martin Andersson; Helena Backman; Gunnar Nordberg; Annika Hagenbjörk; Linnea Hedman; Kåre Eriksson; Bertil Forsberg; Eva Rönmark Journal: Environ Health Date: 2018-04-11 Impact factor: 5.984