Associations between farming environment during infancy and lung function at the age of 31 years
| Farm-related factors during infancy | N | FEV1 difference (mL) | FVC difference (mL) | ||||
|---|---|---|---|---|---|---|---|
| Crude | Adj | 95% CI | Crude | Adj | 95% CI | ||
| Parental professional farming | |||||||
| No | 4367 | 0 | 0 | 0 | 0 | ||
| Yes | 1299 | 44 | 36 | (6 to 67) | 42 | 40 | (5 to 75) |
| Family had farm animals | |||||||
| No | 3930 | 0 | 0 | 0 | 0 | ||
| Yes | 1692 | 39 | 32 | (3 to 61) | 14 | 11 | (−22 to 43) |
| Family had dogs* | |||||||
| No | 2478 | 0 | 0 | 0 | 0 | ||
| Yes | 2995 | 34 | 36 | (10 to 61) | 37 | 37 | (8 to 67) |
| Family had cats* | |||||||
| No | 2767 | 0 | 0 | 0 | 0 | ||
| Yes | 2640 | 18 | 15 | (−11 to 41) | 16 | 14 | (−16 to 44) |
| Number of animal species† | |||||||
| 0 | 1476 | 0 | 0 | 0 | 0 | ||
| 1 | 1539 | 39 | 39 | (6 to 73) | 41 | 41 | (2 to 79) |
| 2 | 1046 | 53 | 56 | (18 to 94) | 32 | 30 | (−14 to 74) |
| 3 | 663 | 67 | 65 | (20 to 109) | 54 | 51 | (0 to 103) |
| 4 or more | 485 | 55 | 44 | (−6 to 94) | 48 | 43 | (−14 to 100) |
| Number of cows | |||||||
| 0 | 3970 | 0 | 0 | 0 | 0 | ||
| 1–4 | 878 | 36 | 31 | (−6 to 67) | 17 | 12 | (−30 to 53) |
| 5 or more | 767 | 46 | 35 | (−3 to 73) | 18 | 16 | (−27 to 59) |
Crude: adjusted for gender and height at the age of 31 years.
Adj: multivariate model, for more detailed information see Methods section.
*Before the age of 7 years.
†Includes cows, pigs, sheep, poultry, minks, cats and dogs.
FEV1, forced expiratory volume in 1 s; FVC, forced vital capacity.