Changes in Australian food anaphylaxis admission rates following introduction of updated allergy prevention guidelines

Abstract

Food anaphylaxis admission rates have increased steadily in recent decades. Global food allergy prevention guidelines recommending early introduction of allergenic foods were introduced in 2015-2016. Australian guidelines to not delay the introduction of allergenic foods were introduced in 2007-2008. Our aim was to examine whether introduction of Australian guidelines (2007-2008) and global allergy prevention guidelines (2015-2016) were associated with reductions in food anaphylaxis admission rates. We compared food anaphylaxis admission rates across 3 periods: 1998-1999 to 2006-2007, 2007-2008 to 2014-2015, and 2015-2016 to 2018-2019. Annual food anaphylaxis admission rates increased 9-fold between 1998-1999 and 2018-2019, from 2.0 per 105 population to 18.2 per 105 population; the highest absolute rates were in those younger than 1 year. When year-on-year rates of change were examined across the 3 time periods, the annual rate of increase slowed after 2007-2008 in those aged 1 to 4 years (17.6%, 6.2%, and 3.9% per year, respectively) and those aged 5 to 9 years (22%, 13.9%, and -2.4%, respectively), and after 2015-2016, in those aged 10 to 14 years (17.5%, 18.0%, and 10.8%, respectively). By contrast, the year-on-year rate of increase accelerated in those younger than 1 year (5.2%, 8.0%, and 18.0%, respectively) and in all age groups older than 15 years. Although food anaphylaxis continues to increase overall, there is preliminary evidence indicating a slowing in the year-on-year rate of increase among those aged 1 to 4, 5 to 9, and 10 to 14 years, coinciding with introduction of updated infant feeding and allergy prevention guidelines in 2007-2008 and 2015-2016. Changes to the guidelines may have contributed to an attenuated rate of increase in food anaphylaxis in these age groups, as well as to increased rates in those younger than 1 year.