Table 3. Childhood wheezing, family history, inhaler use and hospital admissions for all children less than 5 years-of-age compared by gestational age (unadjusted OR).

	Very Preterm	Moderate Preterm	Late Preterm	Full Term
	N = 502	N = 479	N = 1,130	N = 1,402
Wheeze-ever (%)	325 (64.7%)	266 (55.5%)	581 (51.4%)	571 (40.7%)
OR (95% CI)	2.7 (2.2, 3.3)	1.8 (1.5, 2.2)	1.5 (1.3, 1.8)
p-value	<0.001	<0.001	<0.001
aOR (95% CI)#	2.6 (2.1, 3.3)	1.8 (1.4, 2.2)	1.5 (1.2, 1.7)
aOR (95% CI)^	2.8 (2.2, 3.4)	1.9 (1.5, 2.3)	1.5 (1.3, 1.8)
Recent wheeze (%)	201 (40%)	160 (33.4%)	326 (28.8%)	261 (18.6%)
OR (95% CI)	2.9 (2.3, 5.7)	2.2 (1.7, 2.8)	1.8 (1.5, 2.1)
p-value	<0.001	<0.001	<0.001
aOR (95% CI)#	2.9 (2.3, 3.6)	2.2 (1.7, 2.8)	1.7 (1.4,2.0)
aOR (95% CI)^	3.0 (2.4, 3.8)	2.3 (1.8, 2.9)	1.7 (1.4,2.1)
Mild wheeze (%)	183 (36.5%)	146 (30.5%)	291 (25.8%)	238 (17%)
OR (95% CI)	2.8 (2.2, 3.5)	2.1 (1.7, 2.7)	1.7 (1.4, 2.1)
p-value	<0.001	<0.001	<0.001
Severe wheeze (%)	18 (3.6%)	14 (2.9%)	35 (3.1%)	23 (1.6%)
OR (95% CI)	2.2 (1.2, 4.2)	1.8 (0.9, 3.5)	1.9 (1.1, 3.3)
p-value	<0.05	0.1	<0.05
Family history of atopy (%)	131 (26.1%)	115 (24%)	355 (31.4%)	380 (27.1%)
OR (95% CI)	1.0 (0.8,1.2)	0.9 (0.7, 1.1)	1.2 (1.0, 1.5)
p-value	0.662	0.184	0.018
Any inhaler medication use (%)	167 (33.3%)	95 (19.8%)	222 (19.6%)	167 (11.9%)
OR (95% CI)	3.7 (2.9, 4.7)	1.8 (1.4, 2.4)	1.8 (1.5, 2.5)
p-value	<0.001	<0.001	<0.001
Corticosteroid inhaler medication use (%)	52 (10.4%)	27 (5.6%)	76 (6.7%)	41 (2.9%)
OR (95% CI)	3.8 (2.5, 5.9)	2.0 (1.2, 3.3)	2.4 (1.6, 3.5)
p-value	<0.001	0.007	<0.001
Hospital admission with breathing related problem (last 12 months) (%)	110 (21.9%)	58 (12.1%)	112 (9.9%)	77 (5.5%)
OR (95% CI)	4.8 (3.5, 6.6)	2.4 (1.7, 3.4)	1.9 (1.4, 2.6)
p-value	<0.001	<0.001	<0.001

^#Confounding factors–gender, FH of atopy, maternal smoking during pregnancy, CS, maternal history of asthma, breastfeeding at birth, current maternal smoking, social status, ethnicity, and other family member smoking.

^{^}adjusted for Family history of atopy only.