Table 3.
Relationship between type of feeding and number of episodes of bronchiolitis
| Hospital discharge to 12th month | 2nd to 12th month | 4th to 12th month | 6th to 12th month | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Category | no. bronchiolitis / children at discharge | aIR (95% CI) | p | no. bronchiolitis / children at 2nd month | aIR (95% CI) | p | no. bronchiolitis / children at 4th month | aIR (95% CI) | p | no. bronchiolitis / children at 6th month | aIR (95% CI) | p |
| Type of feeding | ||||||||||||
| Infant formula only | 120/163 | 1(ref.) | . | 190/295 | 1(ref.) | . | 217/383 | 1(ref.) | . | 207/477 | 1(ref.) | . |
| Mixed (breastfeeding and infant formula) | 115/264 | 0.64 (0.49, 0.84) | 0.001 | 63/179 | 0.59 (0.44, 0.79) | 0.000 | 53/162 | 0.63 (0.47, 0.86) | 0.004 | 44/181 | 0.63 (0.45, 0.87) | 0.006 |
| Breastfeeding | 179/479 | 0.59 (0.46, 0.75) | 0.000 | 142/418 | 0.62 (0.49, 0.78) | 0.000 | 101/348 | 0.59 (0.46, 0.76) | 0.000 | 61/234 | 0.69 (0.51, 0.93) | 0.016 |
| Change in type of feeding | ||||||||||||
| Infant formula only | 115/161 | 1(ref.) | . | 178/296 | 1(ref.) | . | 185/383 | 1(ref.) | . | |||
| Previously breastfed, currently infant formula only | 75/134 | 0.79 (0.58, 1.06) | 0.114 | 39/87 | 0.83 (0.58, 1.19) | 0.298 | 22/94 | 0.56 (0.36, 0.88) | 0.012 | |||
| Previously exclusive breastfeeding or any breastfeeding, currently any breastfeeding | 63/179 | 0.53 (0.39, 0.73) | 0.000 | 53/162 | 0.61 (0.45, 0.83) | 0.002 | 44/181 | 0.57 (0.41, 0.80) | 0.001 | |||
| Exclusive breastfeeding since birth | 142/418 | 0.56 (0.43, 0.73) | 0.000 | 101/348 | 0.57 (0.44, 0.74) | 0.000 | 61/234 | 0.63 (0.46, 0.85) | 0.003 | |||
| Duration of breastfeeding | ||||||||||||
| No breastfeeding | 139/181 | 1(ref.) | . | 125/181 | 1(ref.) | . | 102/181 | 1(ref.) | . | |||
| Stop breastfeeding before the Xa month | 43/109 | 0.48 (0.34, 0.68) | 0.000 | 94/216 | 0.58 (0.44, 0.76) | 0.000 | 117/321 | 0.63 (0.48, 0.82) | 0.001 | |||
| Continuing to breastfeed in the Xa month | 213/576 | 0.52 (0.41, 0.65) | 0.000 | 149/469 | 0.51 (0.40, 0.66) | 0.000 | 90/364 | 0.50 (0.37, 0.67) | 0.000 | |||
adjusted for maternal smoking, maternal occupational status, twin pregnancy, gestation length, birth order, daycare attendance and months with which he begins kindergarten
aIR Adjusted Incidence Ratio
CI Confidence Interval
a X is the time month