Revision of threshold levels for evoking pollinosis to oak, pine, Japanese hop, and ragweed in the metropolitan area Seoul, Korea

ABSTRACT

Purpose@#The threshold levels for symptom development of pollinosis vary among studies and countries. This study aimed to determine currently used threshold levels for it. @*Methods@#Oak, pine, Japanese hop, and ragweed pollen samples were collected daily for 8 years from the Seoul and Guri areas. A total of 792 subjects with allergy to these pollens were recruited. The symptom index (SI) was assessed through telephone interviews and allergy questionnaires, and data were analyzed using decision tree. @*Results@#The risk index for oak pollen allergy was “mild” when the pollen count was 0–2 grains/m3 , “moderate” when it was 3–11 grains/m3 , “severe” when it was 12–28 grains/m3 , and “dangerous” when it was ≥ 29 grains/m3 . The risk level for pine pollen allergy was “mild” when the pollen count was 0–4 grains/m 3 , “moderate” when it was 5–42 grains/m3 , “severe” when it was 43–66 grains/m3 , and “dangerous” when it was ≥ 67 grains/m3 . For Japanese hop pollen allergy, the risk level was “mild” when the pollen count was 0–8 grains/m3 , “moderate” when it was 9–10 grains/m3 , “severe” when it was 11–19 grains/m3 , and “dangerous” when it was ≥ 20 grains/m3 . Finally, for ragweed, the risk level was “mild” when the pollen count was 0–1 grains/m3 , “moderate” when it was 2–6 grains/m3 , “severe” when it was 7–33 grains/m3 , and “dangerous” when it was ≥ 34 grains/m3 . @*Conclusions@#Revising the threshold levels for the risk index for pollen allergies may be useful for developing pollen prediction models for patients with pollen allergies in Korea.