Patient characteristics and outcome
A total of 316 food–allergy patients were enrolled in the IQ-OFA study, and 128 met the eligibility criteria of the present study. The OFC indicated that one patient had outgrown the egg allergy and was therefore excluded. The remaining 127 patients were followed up for 1 year after having received dietary advice, and 93 patients (73.2%) participated in the outcome survey (Figure 1). Fifty-seven patients (61.3%) were classified in the Outgrowing (Group O) and 36 (38.7%) in the Non-outgrowing (Group N). The distributions of the intake levels at entry (OFC) and at 1 year after OFC in Group N and Group O are shown in Figs. 2A and B. There was a significant leftward shift (toward lower levels) in the distribution in Group N (χ2 test for trend: P=0.0252) and a significant rightward (toward higher levels) shift in Group O (χ2 test for trend: P<0.0001).
Table 1 summarizes the clinical characteristics at the time of OFC. The subjects had a median age of 24 months and were predominantly boys, with comorbid and parental allergic diseases. One–fourth of the subjects had a history of anaphylaxis to some food, and most of them had multiple food allergies, with a median of 4 avoided foods (Table 1).
Comparing the 2 groups, patients in Group N were older and had higher prevalences of atopic dermatitis and asthma. Egg white (EW) and ovomucoid (OM) sIgE levels were also significantly higher in Group N. The groups showed no differences in the proportions of comorbid allergic rhinitis, family history of allergic diseases, food–induced anaphylaxis history or first–time OFC. There was no difference in the number of avoided foods (Table 1).