Table 4. Comparison of environmental factors according to the severity of asthma in children.
| NAEPP classification | Mild intermittent | Mild persistent | Moderate/severe persistent | Total | P value* | Trend P value† |
|---|---|---|---|---|---|---|
| Current exposure to ETS at home | 57/246 (23.2) | 86/250 (34.4) | 61/153 (39.9) | 204/649 (31.4) | 0.001 | < 0.001 |
| Presence of any smoker at home | 97/246 (39.4) | 108/251 (43.0) | 72/153 (47.1) | 277/650 (42.6) | 0.321 | 0.132 |
| Usage of air purifier in exposure to high levels of outdoor PM | 132/245 (53.9) | 141/251 (56.2) | 63/153 (41.2) | 336/649 (51.8) | 0.010 | 0.029 |
| Mold exposure in the previous 12 months | 63/244 (25.8) | 74/251 (29.5) | 52/153 (34.0) | 189/648 (29.2) | 0.217 | 0.081 |
| Current mold exposure | 43/244 (17.6) | 46/251 (18.3) | 41/153 (26.8) | 130/648 (20.1) | 0.058 | 0.039 |
| Current cat ownership | 8/246 (3.3) | 12/251 (4.8) | 9/153 (5.9) | 29/350 (4.5) | 0.443 | 0.204 |
| Current dog ownership | 21/246 (8.5) | 38/251 (15.1) | 25/153 (16.3) | 84/650 (12.9) | 0.032 | 0.015 |
| Current dog ownership with sensitization to dog | 2/244 (0.8) | 13/254 (5.1) | 11/151 (7.3) | 26/649 (4.0) | 0.003 | 0.001 |
| Current mold exposure with sensitization to mold (Aspergillus, Alternaria or Cladosporium) | 7/214 (3.3) | 6/226 (2.7) | 10/138 (7.2) | 23/578 (4.0) | 0.075 | 0.096 |
NAEPP, National Asthma Education and Prevention Program; ETS, environmental tobacco smoke; PM, particulate matter
*χ2 test; †Linear by linear association.