Epinephrine autoinjector prescribing trends: an outpatient population-based study in Olmsted County, Minnesota

Published Online: June 7, 2016

Epinephrine auto-injectors are prescribed for self-treatment of anaphylaxis. The prescription trends over time can be used as an indicator of the overall prevalence of patients who have experienced or are at risk of experiencing anaphylaxis. However, this trend has not been studied at a population level in the United States.

Lee and colleagues in The Journal of Allergy and Clinical Immunology: In Practice identified outpatient prescriptions for epinephrine auto-injectors among residents of Olmsted County, Minnesota, between January 1, 2004 and December 31, 2010. The first prescription per patient during the study period and the first prescription per patient per year were used to calculate incidence rates. Incidence rates per 100,000 person-years were calculated using patients prescribed epinephrine per year as the numerator and age- and sex-specific counts of the population of Olmsted County as the denominator. The relationships of age group, sex, and year of prescription with incidence rates were assessed.

The overall incidence rate of epinephrine auto-injector prescriptions during the study period was 757 per 100,000 person-years. The prescription rates per patient per year increased over time, with an annual rate of increase of 8%, but the rates of first time prescriptions remained stable. For each year, incidence rates overall were higher in women compared to men. From ages 0-19, incidence rates were higher in boys compared to girls. At age 20 and above, incidence rates were higher in women compared to men.

The authors concluded that the overall rate of epinephrine auto-injector prescriptions increased, but the rate of first time prescriptions was stable from 2005-2010. In childhood, boys were more likely to receive a prescription than girls, but this reversed in later ages.

The Journal of Allergy and Clinical Immunology: In Practice is an official journal of the AAAAI, focusing on practical information for the practicing clinician.

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