TABLE III.
Associations between early-life exposures and adult atopy in the ALHS
| Early-life exposures* |
Atopic n (%)† |
Nonatopic n (%) |
Crude OR (95% CI) |
OR (95% CI)‡ |
|---|---|---|---|---|
| Total | 578 | 2526 | ||
| Mother lived on farm while pregnant | ||||
| No | 174 (30.1) | 588 (23.3) | Ref | Ref |
| Yes | 394 (68.2) | 1901 (75.3) | 0.70 (0.57–0.86) | 0.69 (0.55–0.85) |
| Missing | 10 (1.7) | 37 (1.5) | ||
| Mother performed farm activities while pregnant | ||||
| No | 217 (37.5) | 711 (28.1) | Ref | Ref |
| Yes | 326 (56.4) | 1683 (66.6) | 0.63 (0.52–0.77) | 0.60 (0.48–0.74) |
| Missing | 35 (6.1) | 132 (5.2) | ||
| Mother worked with farm animals while pregnant | ||||
| No | 217 (37.5) | 734 (29.1) | Ref | Ref |
| Yes | 305 (52.8) | 1601 (63.4) | 0.64 (0.53–0.78) | 0.62 (0.50–0.77) |
| Missing | 56 (9.7) | 191 (7.6) | ||
| Family lived on farm when born | ||||
| No | 175 (30.3) | 582 (23) | Ref | Ref |
| Yes | 395 (68.3) | 1911 (75.7) | 0.69 (0.56–0.84) | 0.67 (0.54–0.84) |
| Missing | 8 (1.4) | 33 (1.3) | ||
| Farm animal exposure before age 3 | ||||
| No | 182 (31.5) | 638 (25.3) | Ref | Ref |
| Yes | 337 (58.3) | 1656 (65.6) | 0.71 (0.58–0.87) | 0.68 (0.54–0.84) |
| Missing | 59 (10.2) | 232 (9.2) | ||
| Farm animal exposure before age 6 | ||||
| No | 141 (24.4) | 476 (18.8) | Ref | Ref |
| Yes | 419 (72.5) | 1939 (76.8) | 0.73 (0.59–0.90) | 0.68 (0.54–0.86) |
| Missing | 18 (3.1) | 111 (4.4) | ||
| Breast-fed | ||||
| No | 208 (36) | 846 (37.5) | Ref | Ref |
| Yes | 257 (44.5) | 1210 (56.4) | 0.86 (0.71–1.06) | 0.95 (0.76–1.20) |
| Missing | 113 (19.6) | 470 (6.1) | ||
| Indoor furry pets before age 6 | ||||
| No | 396 (37.5) | 1829 (37.5) | Ref | Ref |
| Yes | 167 (56.4) | 644 (56.4) | 1.20 (0.98–1.47) | 1.18 (0.95–1.45) |
| Missing | 15 (6.1) | 53 (6.1) | ||
| Mother smoked cigarettes while pregnant | ||||
| No | 483 (37.5) | 2185 (37.5) | Ref | Ref |
| Yes | 62 (56.4) | 214 (56.4) | 1.31 (0.97–1.77) | 1.14 (0.84–1.57) |
| Missing | 33 (6.1) | 127 (6.1) | ||
| Parents smoked cigarettes in house before age 6 | ||||
| No | 243 (37.5) | 1126 (37.5) | Ref | Ref |
| Yes | 315 (56.4) | 1322 (56.4) | 1.10 (0.92–1.33) | 1.05 (0.86–1.27) |
| Missing | 20 (6.1) | 78 (6.1) | ||
*
Exposures are modeled individually, one at a time.
†
Any atopy defined 1 or more allergen-specific IgEs > 0.70 IU/mL.
‡
Logistic regression used to estimate ORs adjusted for age, sex, race, state, asthma case-control status, and pack years.