Changes in Sensitization Rates to Pollen Allergens in Allergic Patients in the Southern Part of Gyeonggi Province Over the Last 10 Years

Abstract

Background: Pollen is a typical outdoor allergen, which is known as a major factor causing respiratory allergic diseases. Objective : This study was designed to observe changes in the sensitization rate to pollen allergens and their characteristics in the southern part of Gyeonggi Province over the last 10 years. Method: Targeting 7,103 patients in total, the results of allergy skin prick tests were obtained in 1999, 2005 and 2008. We assessed changes in skin reactivity to 13 major inhalant allergens, including alder, oak and beech, that cause pollinosis in spring as well as mugwort, ragweed and Hop J pollens that cause pollinosis in autumn, based on the rates of allergen/histamine wheal responses. Higher ratios than 1 were regarded as positive results. Result: The sensitization rates to tree pollens were increased gradually in 1999, 2005 and 2008. The sensitization rates to alder were 5.5% in 1999, 6.2%in 2005 and 9% in 2008 those to oak were 6.7% in 1999, 8.5% in 2005 and 9.6% in 2008. Also, the sensitization rates to weed pollens were increased gradually in 1999, 2005 and 2008 as well. The sensitization rates to mugwort were 11.3% in 1999, 13.1% in 2005 and 15.2% in 2008; those to Hop J were 7.1% in 1999, 8.0% in 2005 and 9.6% in 2008. Especially in cases of Hop J, the proportion of patients with high rates (more than 5+) tended to increase from 27.5% in 1999 to 31.3% in 2005 and 36.9% in 2008. The time point where the sensitization rate started to obviously increase was advanced from September to July, which implies the extension of the sensitization period. Conclusion: The sensitization rates to tree and weed pollens have increased significantly in the southern part of Gyeonggi Province over the last 10 years, which has been noted among the patients at different ages, especially young children and adults over their 40s. An increase in the degree of skin reactivity and the extension of the sensitization period were observed in cases of Hop J.