From: Impact of air pollution on respiratory diseases in children with recurrent wheezing or asthma
 | Wheezing/asthma (n = 364) | Healthy children (n = 389) | p-value | ||
---|---|---|---|---|---|
 | N | % | N | % |  |
Age distribution | Â | Â | Â | Â | Â |
2-5 yrs | 155 | 42.6 | 152 | 39.1 | Â |
5-18 yrs | 209 | 57.4 | 237 | 60.9 | 0.365 |
Sex | Â | Â | Â | Â | Â |
Male | 237 | 65.1 | 196 | 50.4 | Â |
Female | 127 | 34.9 | 193 | 49.6 | <0.001 |
Parental education a | Â | Â | Â | Â | Â |
Primary/secondary for both parents | 36 | 9.9 | 17 | 4.4 | Â |
High school for at least one parent | 161 | 44.5 | 129 | 33.2 | Â |
University degree for at least one parent | 165 | 45.6 | 243 | 62.5 | <0.001 |
Paternal smoking during pregnancy a | Â | Â | Â | Â | Â |
No | 255 | 71.2 | 312 | 81.0 | Â |
Yes | 103 | 28.8 | 73 | 19.0 | 0.002 |
Maternal smoking during pregnancy a | Â | Â | Â | Â | Â |
No | 329 | 91.6 | 353 | 91.5 | Â |
Yes | 30 | 8.4 | 33 | 8.5 | 0.92 |
Parental history of atopy a | Â | Â | Â | Â | Â |
No | 269 | 74.9 | 343 | 90.5 | Â |
Yes | 90 | 25.1 | 36 | 9.5 | <0.001 |
Gestational age (weeks) a | Â | Â | Â | Â | Â |
<37 | 56 | 15.6 | 26 | 6.8 | Â |
≥37 | 304 | 84.4 | 357 | 93.2 | <0.001 |
Birth weight (grams) a | Â | Â | Â | Â | Â |
≤2500 | 44 | 12.2 | 31 | 8.0 |  |
>2500-3500 | 227 | 62.9 | 245 | 63.1 | Â |
>3500 | 90 | 24.9 | 112 | 28.9 | 0.11 |
Neonatal respiratory disease a | Â | Â | Â | Â | Â |
No | 317 | 88.1 | 372 | 95.9 | Â |
Yes | 43 | 11.9 | 16 | 4.1 | <0.001 |
Neonatal cardiac disease a | Â | Â | Â | Â | Â |
No | 335 | 94.4 | 380 | 97.9 | Â |
Yes | 20 | 5.6 | 8 | 2.1 | 0.01 |
Breastfeeding (months) | Â | Â | Â | Â | Â |
No breastfeeding | 70 | 19.2 | 56 | 14.4 | Â |
≤6 | 152 | 41.8 | 152 | 39.1 |  |
>6 | 142 | 39.0 | 181 | 46.5 | 0.07 |
Previous hospitalization for respiratory disease a | Â | Â | Â | Â | Â |
No | 187 | 52.2 | 339 | 87.4 | Â |
Yes | 171 | 47.8 | 49 | 12.6 | <0.001 |
Home type a | Â | Â | Â | Â | Â |
Flat | 318 | 87.8 | 364 | 93.8 | Â |
House/villa | 44 | 12.2 | 24 | 6.2 | 0.004 |
Home size (m 2 ) a | Â | Â | Â | Â | Â |
≤90 | 155 | 43.9 | 123 | 32.8 |  |
>90-110 | 103 | 29.2 | 127 | 33.9 | Â |
>110 | 95 | 26.9 | 125 | 33.3 | 0.008 |
Proximity to car-traffic | Â | Â | Â | Â | Â |
No | 168 | 46.2 | 169 | 43.4 | Â |
Yes | 196 | 53.8 | 220 | 56.6 | 0.46 |
Proximity to truck-traffic | Â | Â | Â | Â | Â |
No | 304 | 83.5 | 342 | 87.9 | Â |
Yes | 60 | 16.5 | 47 | 12.1 | 0.08 |
Proximity to factories | Â | Â | Â | Â | Â |
No | 327 | 89.8 | 375 | 96.4 | Â |
Yes | 37 | 10.2 | 14 | 3.6 | <0.001 |
Residence in a green area | Â | Â | Â | Â | Â |
No | 145 | 39.8 | 183 | 47.0 | Â |
Yes | 219 | 60.2 | 206 | 53.0 | 0.046 |
Smokers at home a | Â | Â | Â | Â | Â |
No | 241 | 67.7 | 297 | 77.1 | Â |
Yes | 115 | 32.3 | 88 | 22.9 | 0.004 |
Presence of a stove/fireplace at home a | Â | Â | Â | Â | Â |
No | 327 | 90.6 | 358 | 92.3 | Â |
Yes | 34 | 9.4 | 30 | 7.7 | 0.41 |
Presence of an air conditioning system at home a | Â | Â | Â | Â | Â |
No | 170 | 47.1 | 145 | 37.4 | Â |
Yes | 191 | 52.9 | 243 | 62.6 | 0.007 |
Presence of dogs at home a | Â | Â | Â | Â | Â |
No | 319 | 88.4 | 351 | 90.7 | Â |
Yes | 42 | 11.6 | 36 | 9.3 | 0.30 |
Presence of cats at home a | Â | Â | Â | Â | Â |
No | 338 | 93.6 | 351 | 90.7 | Â |
Yes | 23 | 6.4 | 36 | 9.3 | 0.14 |