Anaphylaxis fatalities and admissions in Australia

Background: Detailed data on fatal anaphylaxis are limited, with national anaphylaxis fatality data for the United Kingdom and food-induced anaphylaxis fatality data for the United States. Time trends for anaphylaxis fatalities are not available. Objective: We examined causes, demographics, and time trends for anaphylaxis fatalities in Australia between January 1997 and December 2005 and compared these with findings for anaphylaxis admissions. Methods: Data on anaphylaxis deaths and hospital admissions were extracted from a national database. Death certificate codes were analyzed to determine the likely cause and associated comorbidities. Results: There were 112 anaphylaxis fatalities in Australia over 9 years. Causes were as follows: food, 7 (6%); drugs, 22 (20%); probable drugs, 42 (38%); insect stings, 20 (18%); undetermined, 15 (13%); and other, 6 (5%). All food-induced anaphylaxis fatalities occurred between 8 and 35 years of age with female preponderance, despite the majority of food-induced anaphylaxis admissions occurring in children less than 5 years of age. Most insect sting-induced anaphylaxis deaths occurred between 35 and 84 years almost exclusively in male subjects, although bee sting-induced admissions peak between 5 and 9 years of age with a male/female ratio of 2.7. However, most drug-induced anaphylaxis deaths occurred between 55 and 85 years with equal sex distribution similar to drug-induced anaphylaxis admissions. There was no evidence of an increase in death rates for food-induced anaphylaxis, despite food-induced anaphylaxis admissions increasing approximately 350%. In contrast, drug-induced anaphylaxis deaths increased approximately 300% compared with an approximately 150% increase in drug-induced anaphylaxis admissions. Conclusion: The demographics for anaphylaxis deaths are different to those for anaphylaxis presentations. Anaphylaxis mortality rates remain low and stable, despite increasing anaphylaxis prevalence, with the exception of drug-induced anaphylaxis deaths, which have increased. (J Allergy Clin Immunol 2009;123:434-42.)