Fatal anaphylaxis in the United States, 1999-2010: Temporal patterns and demographic associations

Abstract

Background Anaphylaxis-related deaths in the United States (US) have not been well characterized in recent years. Objectives To define epidemiological features and time trends of fatal anaphylaxis in the US from 1999 to 2010. Methods Anaphylaxis-related deaths were identified by the 10th clinical modification of the International Classification of Diseases (ICD-10) system diagnostic codes on death certificates from the US National Mortality Database. Rates were calculated using census population estimates. Results There were a total of 2,458 anaphylaxis deaths in the US from 1999 to 2010. Medications were the most common cause (58.8%), followed by unspecified anaphylaxis (19.3%), venom (15.2%), and food (6.7%). There was a significant increase in fatal drug anaphylaxis over twelve years: from 0.27 (95%CI: 0.23-0.30) in 1999-2001 to 0.51 (95%CI: 0.47-0.56) per million in 2008-2010, P<0.001. Fatal anaphylaxis due to medications, food, and unspecified allergens was significantly associated with African-American race and older age, P<0.001. Fatal anaphylaxis to venom was significantly associated with White race, older age, and male gender, P<0.001. The rates of fatal anaphylaxis to foods in African-American males increased from 0.06 (95%CI 0.01-0.17) in 1999-2001 to 0.21 (95%CI 0.11-0.37) per million in 2008-2010, P<0.001. The rates of unspecified fatal anaphylaxis decreased overtime from 0.30 (95%CI: 0.26-0.34) in 1999-2001 to 0.09 (95%CI: 0.07-0.11) per million in 2008-2010, P<0.001. Conclusion There are strong and disparate associations between race and specific classes of anaphylaxis mortality in the United States. The increase in medication-related anaphylaxis deaths likely relates to increased medication and radiocontrast use, enhanced diagnosis, and coding changes.