Anaphylaxis: risk factors for recurrence

Clin Exp Allergy. 2003 Aug;33(8):1033-40. doi: 10.1046/j.1365-2222.2003.01671.x.


Background: There are few studies on the incidence or recurrence of anaphylaxis.

Objective: To examine the incidence of anaphylaxis and risk factors for recurrence.

Methods: A prospective study of 432 patients referred to a community-based specialist practice in the Australian Capital Territory with anaphylaxis, followed by a survey to obtain information on recurrence.

Results: Of 432 patients (48% male, 73% atopic, mean 27.4 years, SD 19.5, median 26) with anaphylaxis, 260 patients were seen after their first episode; 172 experienced 584 previous reactions. fifty-four percent of index episodes were treated in hospital. Aetiology was identified in 91.6% patients: food (61%), stinging insects (20.4%) or medication (8.3%). The minimum occurrence and incidence of new cases of anaphylaxis was estimated at 12.6 and 9.9 episodes/100,000 patient-years, respectively. Follow-up data were obtained from 304 patients (674 patient-years). One hundred and thirty experienced further symptoms (45 serious), 35 required hospitalization and 19 administered adrenaline. Accidental ingestion of peanut/tree nut caused the largest number of relapses, but the highest risk of recurrence was associated with sensitivity to wheat and/or exercise. Rates of overall and serious recurrence were 57 and 10 episodes/100 patient-years, respectively. Of those prescribed adrenaline, 3/4 carried it, 2/3 were in date, and only 1/2 patients faced with serious symptoms administered adrenaline. Five patients each developed new triggers for anaphylaxis, or re-presented with significant psychiatric symptoms.

Conclusion: In any 1 year, 1/12 patients who have suffered anaphylaxis will experience recurrence, and 1/50 will require hospital treatment or use adrenaline. Compliance with carrying and using adrenaline is poor. Occasional patients develop new triggers or suffer psychiatric morbidity.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Anaphylaxis / drug therapy
  • Anaphylaxis / epidemiology
  • Anaphylaxis / etiology*
  • Animals
  • Australian Capital Territory / epidemiology
  • Child
  • Child, Preschool
  • Epinephrine / therapeutic use
  • Exercise
  • Female
  • Follow-Up Studies
  • Food Hypersensitivity / complications
  • Food Hypersensitivity / epidemiology
  • Humans
  • Incidence
  • Infant
  • Insect Bites and Stings / complications
  • Insect Bites and Stings / epidemiology
  • Male
  • Middle Aged
  • Patient Compliance
  • Prospective Studies
  • Recurrence
  • Risk Factors
  • Seasons
  • Skin Tests / methods


  • Epinephrine