TABLE 1

Unadjusted and adjusted associations between weight gain in the first year of life and wheezing phenotypes using most-likely phenotype, and using the No/infrequent-wheezing phenotype as the reference category

Relative risk ratio (95% CI) p-value
Early wheezePersistent wheezeLate wheeze
Unadjusted (n=9353)
 Subjects n (%)1232 (13.2%)863 (9.2%)295 (3.2%)
 Weight gain 6–12 months of age#1.29 (1.13–1.46)
8.40×10−5		1.12 (0.97–1.30)
0.13		1.01 (0.79–1.30)
0.93
Adjusted (n=6161)
 Subjects n (%)802 (13.0%)581 (9.4%)182 (3.0%)
 Weight gain birth to 6–12 months of age#1.21 (1.03–1.42)
0.02		0.99 (0.82–1.19)
0.89		1.04 (0.76–1.42)
0.82
 Sex (Male)1.25 (1.07–1.45)
0.01		1.81 (1.51–2.17)
8.66×10-11		1.15 (0.85–1.54)
0.37
 IUGR1.15 (0.91–1.45)
0.17		0.99 (0.74–1.32)
0.92		0.46 (0.24–0.88)
0.02
 Smoking during pregnancy1.37 (1.16–1.62)
0.00028		1.32 (1.09–1.61)
0.005		1.16 (0.83–1.62)
0.38
 Social class (Lowest 5)1.53 (1.24–1.90)
0.000091		1.12 (0.89–1.42)
0.343		1.55 (1.03–2.342)
0.04
 Social class (4)1.12 (0.79–1.58)
0.54		1.02 (0.70–1.49)
0.92		1.23 (0.64–2.38)
0.54
 Social class (3)1.05 (0.69–1.61)
0.82		0.72 (0.43–1.21)
0.22		0.15 (0.02–1.08)
0.06
 Social class (2)1.18 (0.94–1.48)
0.16		0.91 (0.70–1.19)
0.50		1.22 (0.78–1.89)
0.38
 C-section delivery1.10 (0.91–1.34)
0.31		1.27 (1.03–1.57)
0.03		0.81 (0.54–1.23)
0.33
 Breastfeeding (Yes)0.87 (0.73–1.03)
0.10		0.89 (0.72–1.07)
0.19		0.96 (0.69–1.33)
0.78
 Postnatal smoking1.11 (0.93–1.32)
0.27		0.96 (0.77–1.18)
0.67		0.99 (0.69–1.41)
0.95
 Childcare (Formal)1.35 (1.06–1.71)
0.01		0.71 (0.53–0.96)
0.02		1.27 (0.79–2.02)
0.33
 Childcare (Informal)1.09 (0.92–1.29)
0.34		0.89 (0.74–1.08)
0.24		1.22 (0.88–1.70)
0.23

Excluded: non-Caucasian, non-term, non-singletons. IUGR: intrauterine growth restriction. #: catch-up growth was defined as a change in z-score of >0.67 between birth weight and weight at 6–12 months of age; : adjusted for gender, IUGR, maternal smoking during pregnancy, social class, and c-section delivery using complete dataset.