TABLE 4.
Demographic and clinical characteristics of CHILD cohort subjects with and without inhalant atopy (inhalant allergen sensitization) at age 5 yearsa
| Variable | Cohort | Inhalant atopy | No inhalant atopy | P value |
|---|---|---|---|---|
| No. of patients | 2,539 | 438 | 2,101 | |
| Institution, no. (%) | <0.001 | |||
| Edmonton | 544 (21.4) | 89 (20.3) | 455 (21.7) | |
| Toronto | 519 (20.4) | 136 (31.1) | 383 (18.2) | |
| Vancouver | 601 (23.7) | 147 (33.6) | 454 (21.6) | |
| Winnipeg | 875 (34.5) | 66 (15.1) | 809 (38.5) | |
| Antibiotic use by age 3 mo, no. (%) | 0.055 | |||
| 452 (17.8%) | 64 (14.6%) | 388 (18.5%) | ||
| Antibiotic use by age 1 yr, no. (%) | 0.039 | |||
| 451 (17.8) | 93 (21.2) | 358 (17) | ||
| Antifungal use by 3 mo, no. (%) | 0.22 | |||
| Confirmed | 24 (0.9) | 3 (0.7) | 21 (1) | |
| Unknown | 2,231 (87.9) | 361 (82.4) | 1,870 (89) | |
| Antifungal use by age 1 yr, no. (%) | 0.15 | |||
| Confirmed | 26 (1) | 3 (0.7) | 23 (1.1) | |
| Unknown | 2231 (87.9) | 361 (82.4) | 1,870 (89) | |
| Gestational age at delivery (wks) | 0.76 | |||
| Median (range) | 39.7 (34, 42.9) | 39.7 (34.3, 42) | 39.7 (34, 42.9) | |
| IQR (Q1, Q3) | 38.9, 40.6 | 38.9, 40.4 | 38.9, 40.6 | |
| Unknown, no. (%) | 127 (5) | 16 (3.7) | 111 (5.3) | |
| Mode of delivery, no. (%) | 0.0011 | |||
| Vaginal | 1,879 (74) | 294 (67.1) | 1,585 (75.4) | |
| C-section with labor | 324 (12.8) | 69 (15.8) | 255 (12.1) | |
| C-section without labor | 306 (12.1) | 70 (16) | 236 (11.2) | |
| Unknown | 30 (1.2) | 5 (1.1) | 25 (1.2) | |
| Having older sibling, no. (%) | 0.34 | |||
| Confirmed | 1,206 (47.5) | 198 (45.2) | 1,008 (48) | |
| Unknown | 45 (1.8) | 9 (2.1) | 36 (1.7) | |
| Male, no. (%) | <0.001 | |||
| 1,350 (53.2) | 285 (65.1) | 1,065 (50.7) | ||
| Birth wt Z score | 0.17 | |||
| Median (range) | −0.1 (−5.9, 15.8) | −0.1 (−5.9, 14.9) | −0.1 (−3.1, 15.8) | |
| IQR (Q1, Q3) | −0.7, 0.6 | −0.7, 0.5 | −0.7, 0.6 | |
| Unknown, no. (%) | 127 (5) | 16 (3.7) | 111 (5.3) | |
| Parental atopy, no. (%) | <0.001 | |||
| Confirmed | 1,997 (78.7) | 384 (87.7) | 1,613 (76.8) | |
| Unknown | 68 (2.7) | 11 (2.5) | 57 (2.7) | |
| Duration of exclusive breastfeeding (mo) | 0.33 | |||
| Median (range) | 4 (0, 9) | 4 (0, 6) | 4 (0, 9) | |
| IQR (Q1, Q3) | 0.5, 5 | 0.5, 5 | 0.5, 5 | |
| Unknown, no. (%) | 62 (2.4) | 7 (1.6) | 55 (2.6) | |
| Tobacco smoke exposure to age 1 yr, no. (%) | 0.029 | |||
| Confirmed | 610 (24) | 89 (20.3) | 521 (24.8) | |
| Unknown | 276 (10.9) | 43 (9.8) | 233 (11.1) | |
| Season of birth, no. (%) | 0.89 | |||
| Spring | 711 (28) | 118 (26.9) | 593 (28.2) | |
| Summer | 624 (24.6) | 108 (24.7) | 516 (24.6) | |
| Fall | 581 (22.9) | 106 (24.2) | 475 (22.6) | |
| Winter | 621 (24.5) | 106 (24.2) | 515 (24.5) | |
| Unknown | 2 (0.1) | 2 (0.1) | ||
| Area type, no. (%) | <0.001 | |||
| Rural | 74 (2.9) | 3 (0.7) | 71 (3.4) | |
| Urban | 775 (30.5) | 171 (39) | 604 (28.7) | |
| Unknown | 1,690 (66.6) | 264 (60.3) | 1,426 (67.9) | |
| Breastfeeding status at 3 mo, no. (%) | 0.72 | |||
| None | 334 (13.2) | 60 (13.7) | 274 (13) | |
| Partial | 657 (25.9) | 118 (26.9) | 539 (25.7) | |
| Exclusive | 1,528 (60.2) | 256 (58.4) | 1,272 (60.5) | |
| Unknown | 20 (0.8) | 4 (0.9) | 16 (0.8) | |
| Breastfeeding status at 12 mo, no. (%) | 0.42 | |||
| Confirmed | 1,164 (45.8) | 195 (44.5) | 969 (46.1) | |
| Unknown | 97 (3.8) | 13 (3) | 84 (4) | |
| Solid food by age 3 mo, no. (%) | 0.92 | |||
| Confirmed | 173 (6.8) | 29 (6.6) | 144 (6.9) | |
| Unknown, n (%) | 126 (5) | 20 (4.6) | 106 (5) | |
| Presence of mold in home, no. (%) | <0.001 | |||
| Confirmed | 979 (38.6) | 214 (48.9) | 765 (36.4) | |
| Unknown | 13 (0.5) | 2 (0.5) | 11 (0.5) | |
| Oral thrush by age 1 yr, no. (%) | 0.81 | |||
| Confirmed | 29 (1.1) | 4 (0.9) | 25 (1.2) | |
| Unknown | 345 (13.6) | 53 (12.1) | 292 (13.9) | |
| Ethnicity of child, no. (%) | <0.001 | |||
| Caucasian | 1,628 (64.1) | 236 (53.9) | 1,392 (66.3) | |
| East Asian | 80 (3.2) | 28 (6.4) | 52 (2.5) | |
| Multiracial | 582 (22.9) | 128 (29.2) | 454 (21.6) | |
| South Asian | 58 (2.3) | 12 (2.7) | 46 (2.2) | |
| Southeast Asian | 66 (2.6) | 21 (4.8) | 45 (2.1) | |
| Other | 94 (3.7) | 12 (2.7) | 82 (3.9) | |
| Unknown | 31 (1.2) | 1 (0.2) | 30 (1.4) |
a
Wilcoxon rank sum test and Fisher’s exact test were used for continuous and categorical variables, respectively.