Table 2. Associations between residential proximity to a major roadway (<417 meters [N = 56] versus >417 meters [N = 168]) and primary and secondary outcomes in asthmatic children.
| Outcome variable | Children living <417 meters with outcome | Children living >417 meters with outcome | Adjusted | 95% CI | p-value |
| N (%) | N (%) | OR1 | |||
| Wheezing more than twice weekly | 27 (48) | 43 (26) | 2.24 | 1.14, 4.42 | 0.02 |
| Daily wheezing (5 of 7 days per week) | 13 (23) | 16 (9) | 2.63 | 1.10, 6.26 | 0.029 |
| Healthcare utilization for asthma (previous 12 months) | |||||
| Emergency room visit | 40 (71) | 86 (51) | 1.86 | 0.92, 3.76 | 0.086 |
| Hospitalization2 | 31(55) | 48 (29) | 2.45 | 1.23, 4.89 | 0.011 |
| Intensive care unit admission | 19 (34) | 29 (17) | 2.41 | 1.08, 5.36 | 0.031 |
| Airflow limitation | |||||
| FEV1<80% of predicted value | 16 (29) | 35 (21) | 1.27 | 0.59, 2.71 | 0.544 |
| FEV1/FVC<80% of predicted value | 15 (27) | 26 (15) | 2.03 | 0.93, 4.44 | 0.075 |
| FEF25–75<80% of predicted value | 39 (70) | 89 (53) | 2.26 | 1.04, 4.95 | 0.041 |
1
Adjusted for payor status (private insurance versus Medicaid), race (white versus non-white), parental history of asthma (yes versus no), environmental tobacco smoke exposure at least one day per week (yes versus no), and history of gastroesophageal reflux (yes versus no).
2
Defined as a hospital stay ≥24 hours.