Table 3.
Associations between traffic indicators and asthma symptoms and cough or phlegm
| Asthma symptoms | Cough or phlegm | |||||||
|---|---|---|---|---|---|---|---|---|
| n cases | (%) | OR* | 95% CI | n cases | (%) | OR* | 95% CI | |
| Traffic density | ||||||||
| Absent | 564 | 12.5 | 1.00 | 270 | 6.0 | 1.00 | ||
| Low | 1,228 | 12.6 | 1.04 | 0.93–1.16 | 558 | 5.7 | 0.94 | 0.80–1.10 |
| Moderate | 1,375 | 13.8 | 1.13 | 1.01–1.26 | 689 | 6.9 | 1.04 | 0.89–1.22 |
| High | 795 | 14.6 | 1.17 | 1.03–1.33 | 475 | 8.7 | 1.24 | 1.04–1.49 |
| Frequency cars transit | ||||||||
| Never | 309 | 12.7 | 1.00 | 142 | 5.9 | 1.00 | ||
| Sometimes | 1,147 | 12.1 | 0.95 | 0.83–1.10 | 517 | 5.5 | 0.90 | 0.74–1.10 |
| Frequently | 1,399 | 13.6 | 1.06 | 0.93–1.22 | 679 | 6.6 | 1.02 | 0.84–1.26 |
| Continuously | 1,108 | 14.9 | 1.16 | 1.00–1.33 | 656 | 8.8 | 1.32 | 1.08–1.63 |
| Frequency trucks transit | ||||||||
| Never | 1,412 | 12.3 | 1.00 | 652 | 5.7 | 1.00 | ||
| Sometimes | 1,644 | 13.6 | 1.10 | 1.02–1.19 | 812 | 6.7 | 1.14 | 1.02–1.26 |
| Frequently | 682 | 14.5 | 1.16 | 1.05–1.29 | 399 | 8.5 | 1.41 | 1.23–1.61 |
| Continuously | 211 | 15.7 | 1.27 | 1.08–1.50 | 132 | 9.8 | 1.67 | 1.36–2.06 |
* All ORs were adjusted for study centre, age, sex, parental asthma or allergies, parental education, passive smoke at home, indoor moulds, season, person filling the questionnaire, floor level of the apartment and change of residence.