Table 2.

Relationship between type of feeding and diagnosed with at least one episode 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	aOR (95% CI)	p	no. bronchiolitis / children at 2nd month	aOR (95% CI)	p	no. bronchiolitis / children at 4th month	aOR (95% CI)	p	no. bronchiolitis / children at 6th month	aOR (95% CI)	p
Type of feeding
Infant formula only	61/163	1(ref.)	.	96/295	1(ref.)	.	118/383	1(ref.)	.	125/477	1(ref.)	.
Mixed (breastfeeding and infant formula)	70/264	0.60 (0.39, 0.94)	0.02	44/179	0.69 (0.44, 1.06)	0.09	40/162	0.77 (0.49, 1.19)	0.24	36/181	0.73 (0.47, 1.14)	0.17
Breastfeeding	123/479	0.61 (0.41, 0.91)	0.02	105/418	0.73 (0.51, 1.05)	0.09	73/348	0.61 (0.43, 0.89)	0.01	42/234	0.67 (0.44, 1.02)	0.06
Change in type of feeding
Infant formula only				61/162	1(ref.)	.	92/296	1(ref.)	.	107/383	1(ref.)	.
Previously breastfed, currently infant formula only				35/134	0.58 (0.35, 0.98)	0.04	26/87	0.95 (0.55, 1.64)	0.85	18/94	0.67 (0.37, 1.22)	0.19
Previously exclusive breastfeeding or any breastfeeding, currently any breastfeeding				44/179	0.54 (0.33, 0.89)	0.01	40/162	0.76 (0.48, 1.20)	0.24	36/181	0.68 (0.43, 1.07)	0.10
Exclusive breastfeeding since birth				105/418	0.58 (0.38, 0.88)	0.01	73/348	0.61 (0.41, 0.90)	0.01	42/234	0.62 (0.40, 0.95)	0.03
Duration of breastfeeding
No breastfeeding				68/181	1(ref.)	.	63/181	1(ref.)	.	57/181	1(ref.)	.
Stop breastfeeding before the Xa month				28/109	0.57 (0.33, 1.00)	0.05	57/216	0.64 (0.41, 1.02)	0.06	77/321	0.69 (0.45, 1.06)	0.09
Continuing to breastfeed in the Xa month				146/576	0.55 (0.38, 0.81)	0.002	108/469	0.53 (0.36, 0.80)	0.002	66/364	0.45 (0.29, 0.70)	< 0.001

adjusted for maternal smoking, maternal occupational status, twin pregnancy, gestation length, birth order, daycare attendance and months with which he begins kindergarten

aOR Adjusted Odds Ratio

CI Confidence Interval

^a X is the time month