Royal Prince Alfred Hospital Royal Prince Alfred Hospital
Allergy Unit

Student research


Risk Factors Associated with Food-Induced Anaphylaxis in Atopic Children,
Aged 0-5 Years: A Case-Control Study

by
Alison Reid
Bachelor of Nutrition and Dietetics, University of Wollongong
Supervisors: Katherine Jukic, Velencia Soutter, Robert Loblay, Anne Swain
October 2007

pdf Full Text - PDF (401 KB)

Abstract

Introduction: The incidence of food allergy and occurrence of food-induced anaphylaxis is increasing. Understanding the epidemiology of anaphylaxis has been challenged by inconsistencies in definition, and lack of a universal grading system. This study defined anaphylaxis as ‘a severe, life threatening allergic reaction, characterised by signs of cutaneous, gastrointestinal, respiratory and cardiovascular compromise’. To date, literature concerning anaphylaxis has primarily researched clinical symptoms, risk factors (typically asthma) and management associated with the reaction. The primary aim of this study was to determine risk factors associated with food-induced anaphylaxis, within an atopic population.

Methods: This retrospective case-control study was carried out at the RPAH Allergy Unit in Sydney. Children were recruited if they were atopic and aged 0-5 years on presentation at the Allergy Unit. The medical records of 672 subjects were reviewed and cases were identified, that is, if the child had a history of anaphylaxis according to our definition (n=218). The following variables were analysed: age and sex of the child, presence or history of eczema and asthma, number of positive SPT’s to food and airborne allergens, and family size and sibling order of the child. Binary logistic regression was used to determine risk factors associated with anaphylaxis according to statistical significance (p<0.05).

Results: Age (p=0.033), eczema (p=0.036), positive SPT to more than one food allergen (p=0.012) and presence of an airborne allergy (p=0.055) were all statistically associated with risk of anaphylaxis. Other variables analysed did not show to be significant (p>0.05). Sibling order and the number of food allergies were excluded as variables (p>0.8).

Conclusion: Establishment of a universal grading system would enable better comparison of the results of this study with other studies. Future research within this population is required to confirm statistical significance or non-significance of nominated variables, and to address potential confounding variables related to determined risk factors.