Increasing Trends in the Nationwide Incidence of Anaphylaxis Visiting Emergency Room in Korea from 2007 to 2013

Rationale: Anaphylaxis is a severe, life threatening allergic reaction, usually presenting at ER. We aimed to study about nationwide prevalence and compare the regional difference in the ER visiting incidence of anaphylaxis in Korea.

Methods: We retrospective analyzed the National Emergency Department Information System records of 117 emergency room in Korea with diagnosis code of anaphylaxis based on ICD-10 codes, T78.0, T78.2, T80.5, T88.6, T63.4 from 2007 to 2013.

Results: The nationwide ER prevalence of anaphylaxis is 10.1 cases per 100,000 in Korea during 2007-2013. Male and female were total 17,454 to 17,423. An Increasing trend of annual incidence rates is observed from 2007 to 2013, such as 2007: 7.3, 2008: 10.9, 2009: 12.8, 2010: 14.7, 2011: 7.0, 2012: 8.2, 2013: 9.6 per 100,000 PY respectively. Among the 16 region, Kangwon province has the most highest incidence (15.8/100.000 PY) followed by Seoul(15.7), Jeju special autonomous province(15.3) Gyeonggi (11.8). Busan has the lowest incidence(3.3). Age specific incidence rates showed a gradual increasing peaking between 19 to 49 years. There is some monthly variance, highest in August and September and lowest in January and February. The final diagnosis code that related food reaction was 3.1%, adverse effect of drug 7.8%, venomous 2.1%, serum 0.45% and unspecified anaphylactic shock 86.6%. The outcomes of ER patients were hospitalization(16.9%), admission to ICU(0.7%) and death(0.1%).

Conclusions: The incidence of anaphylaxis presenting at nationwide ERs in Korea is found to be increasing from 2007 to 2013. The reasons of regional difference and  seasonal variation will be studied further.