Background: Gaining a better understanding of the risk factors for severe anaphylaxis represents a crucial challenge for physicians. This survey aimed to analyse cases of severe food anaphylaxis and assess potential risk factors for severity.

Methods: We retrospectively analysed food anaphylaxis cases recorded by the French-speaking Allergy-Vigilance Network (2002-2021) and compared the main characteristics of grade 3 (Ring classification) and grade 4 cases using univariate and multivariate statistical analyses.

Results: Of the 2621 food anaphylaxis cases reported, 731 (27.9%) were considered severe (grade 3, n = 687 [94%] and grade 4, n = 44 [6%]; 19 deaths). Overall, 56.1% of cases were adults (mean age: 28.3 years) and 53.7% were male. The most frequent triggers were peanut (13.9%), wheat (9.4%), cashew (5.8%), shrimp (5.3%), and cow's milk (4.6%). More grade 4 anaphylaxis cases occurred in children than in adults (26 vs. 18; p = 0.01). In univariate analysis, individuals with grade 4 anaphylaxis were more likely to have a history of allergy to the culprit food (71.1% vs. 42.1%; p < 0.001), asthma diagnosis (59.5% vs. 30.4%; p < 0.001), and peanut as the culprit food (34.1% vs. 12.6%; p < 0.001). In multivariate analysis, factors predictive of grade 4 anaphylaxis were asthma diagnosis (OR [95% CI]: 3.41 [1.56-7.44]; p = 0.002) and peanut as the culprit trigger (OR [95% CI]: 3.46 [1.28-9.34]; p = 0.014).

Conclusions: Our data highlight the risk factors for severe food anaphylaxis, notably a history of asthma and peanut as the culprit food. These individuals should benefit from personalised management strategies.