Western Australia’s rate of anaphylaxis is increasing

Australia lacks a structured reporting system to capture data on the incidence of anaphylaxis, so the true incidence of anaphylaxis is unknown. An anaphylaxis notification scheme was recently established in Victoria but is only available in that state. Researchers in Western Australia have combined several datasets to gain a clearer picture of anaphylaxis events and any change in event rates from 2002 to 2013 in their state.

Four linked administrative datasets from the Western Australian Data Linkage System were used, representing ambulance attendances, emergency department presentations, hospital inpatient admissions and death registrations.

A total 12,637 people (mean age 31.8 years) experienced 15,462 anaphylaxis events between 2002 and 2013. This is a higher rate of total anaphylaxis than previously reported, with more than a 5-fold increase in anaphylaxis events between 2002 and 2013. Anaphylaxis events caused by food increased 1.9-fold across all ages and genders, with the highest rates seen in children aged 0–4 years.

Overall, females had more anaphylaxis events and a higher increase in rates than males, although the broad distribution of events varied by age and gender. While males experienced more anaphylaxis across the youngest age groups, females experienced more anaphylaxis in teen and adult age groups.

The combination of population-level datasets provided a more comprehensive capture of cases, and showed admission rates for anaphylaxis in Western Australia are substantially higher than those previously reported for similar time periods, both in Australia and worldwide.

Reference: Salter et al. 2020 World Allergy Organization Journal. DOI: 10.1016/j.waojou.2020.100480. Available with Open Access.