I know what some of you are thinking: “The other news reports and blog posts are stating ‘1 in 50’ have anaphylaxis”. Note the “nearly” 1 in 50 in the image below; everyone likes to round up! Here are the key components of the research, as conducted by the Asthma and Allergy Foundation of America (AAFA), and published in the Journal of Allergy and Clinical Immunology:
- Two independent nationwide phone surveys were conducted, one with 1000 unselected pubic adults, a second with just over 1000 patients who had previously reported some type of reaction (food, insects, latex) in the past ten years.
- Adjusting with stringent criteria, it was estimated the 5.1% of the public group and 1.6% of the patient group (1 in 60) had probable and very likely anaphylaxis, respectively.
- With the public survey weighing in, AAFA feels that the real number on anaphylaxis prevalence is likely even higher.
- From the patient survey, the most common triggers reported were medications (34%), foods (31%), and insect stings (20%).
- From the public survey, the most common symptoms reported were respiratory (73%), skin (61%), cardiovascular (24%), neurological (15%), and gastrointestinal (7%).
- More than 1-in-6 of the respondents (17%) who reported anaphylaxis also had a history of asthma, potentially putting them at higher risk for complications.
- A majority of the respondents who reported anaphylaxis stated that they had experienced 2 or more reactions in their lifetime; 19% had experienced 5 or more reactions.
- The reactions occurred at home (54%), at a hospital or clinic (13%), at a relative or friend’s home (6.4%), in the workplace (6.1%), at a restaurant (6.1%) or at school (2.6%).
Anaphylaxis is a severe, sudden allergic reaction that typically involves two or more organs, such as the skin, airways, lungs, stomach, heart or blood pressure. Reactions can be deadly. The study posed concerns about the ability to manage a reaction if it occurred.
“One of the most alarming things we found is that, despite the common occurrence of anaphylaxis, most people are not prepared to do the right thing when emergency reactions occur,” says Mike Tringale, Senior Vice President at AAFA and one of the authors of the article.
At risk patients are not getting prescriptions for epinephrine auto-injectors, not keeping their auto-injectors nearby or not using them during allergic reactions when they should. Researchers found that only 11% of survey respondents who experienced anaphylaxis had used epinephrine and only 10% called 911. Within this group 6.4% received no treatment at all and 52% had never received a prescription for an epinephrine auto-injector.
Not all episodes of anaphylaxis are reported and most do not occur in a medical setting, so tracking the actual rate of incidence can be tricky. According to Dr. Robert Wood, the lead author of the article and Director of Allergy & Immunology at Johns Hopkins Children’s Center, “This study provides the first estimate of anaphylaxis prevalence in the United States using a large unbiased survey”.
Source: Anaphylaxis in America: The Prevalence and Characteristics of Anaphylaxis in the United States, August 2013
Report: Anaphylaxis in America, Asthma and Allergy Foundation of America, October 2013