Table 1.
Population characteristics of the 186 children from the Chicago food allergy cohort
| Variables | Non-atopic controls (n = 20) | Sensitized groups
|
||
|---|---|---|---|---|
| Asymptomatic PS (n=58) | Non-anaphylactic PA (n=55) | Anaphylactic PA (n=53) | ||
| Age (years), median (10th–90th) | 7.6 (2.8–11.2) | 7.1 (2.9–13.0) | 5.4 (2.9–9.7) | 7.2 (3.4–13.5) |
| Boy, n (%) | 11 (55.0) | 32 (55.2) | 34 (61.8) | 33 (62.3) |
| Never smoking mother, n (%) | 12 (60.0) | 42 (72.4) | 43 (78.2) | 42 (79.3) |
| Exclusive breast-feeding, n (%) | 5 (26.3) | 14 (24.1) | 14 (25.5) | 11 (20.8) |
| Peanut ingestion ≥1 day/week a, n (%) | 10 (55.6%) | 37 (80.4%) | 0 | 0 |
| Maternal allergic diseases, n (%) | 7 (35.0) | 32 (56.1) | 31 (56.4) | 32 (60.4) |
| Paternal allergic diseases, n (%) | 6 (30.0) | 28 (50.0) | 27 (49.1) | 33 (64.7) |
| Current eczema, n (%) | 0 | 18 (31.0) * | 28 (50.9) | 22 (41.5) |
| Current asthma, n (%) | 0 | 18 (31.0) * | 25 (45.5) | 28 (52.8) ¶ |
| Current hay fever, n (%) | 0 | 25 (43.1) * | 22 (40.0) | 32 (60.4) |
| Allergy to other food, n (%)s | 0 | 21 (36.2) * | 25 (45.5) | 21 (39.6) |
| Total IgE (kU/L), median (10th–90th) | 7.8 (2.0–27.1) | 172.5 (47.1–590.1)* | 405.0 (59.9–1749.9)¶ | 358.4 (107.3–1163.6) ¶ |
| Peanut sIgE (kUA/L), median (10th–90th) | 0 | 0.30 (0.12–2.30)* | 40.2 (0.91–194.3)¶ | 93.9 (9.3–213.5)¶ |
| Peanut sIgE ≥ 14 kUA/L, n (%) | 0 | 0 | 43 (78.2)¶ | 45 (88.2)¶ |
| Percent peanut sIgE, median (10th–90th) b | 0 | 0.00(0.00–0.01)* | 0.12 (0.02–0.36) ¶ | 0.23 (0.04–0.41) ¶,& |
| Peanut SPT MWD (mm), median (10th–90th)c | 0 | 0 (0–5.5) | 11.3 (8.5–19.5) ¶ | 11.0 (7.5–14.0)¶ |
| Peanut SPT MWD ≥ 8 mmc, n (%) | 0 | 1 (2.3) | 32 (94.1)¶ | 20 (87.0)¶ |
PS: peanut sensitization; PA: peanut allergy; MWD: mean wheal diameter; NA: not available
Pair-wise comparison of continuous and categorical variables was performed between non-atopic controls and asymptomatic PS children; between asymptomatic PS children, non-anaphylactic PA cases and anaphylactic PA cases; and between non-anaphylactic and anaphylactic PA cases, using two-sided Wilcoxon Rank Sums tests and Fisher exact tests, respectively.
p<0.01 with non-atopic controls as the reference;
p<0.01 with asymptomatic PS children as the reference;
p<0.01 with non-anaphylactic PA cases as the reference.
The number of children with available information on peanut ingestion was 18, 46, 54 and 53 in the non-atopic, asymptomatic PS, non-anaphylactic and anaphylactic PA groups, respectively.
Two anaphylactic subjects had missing values on peanut sIgE.
The number of children with available SPT data was 18, 44, 34 and 23 in the non-atopic, asymptomatic PS, non-anaphylactic and anaphylactic PA groups, respectively.