Association of birth weight with asthma-related outcomes at age 2 years
Version of Record online: 15 MAY 2006
Copyright © 2006 Wiley-Liss, Inc.
Volume 41, Issue 7, pages 643–648, July 2006
How to Cite
Taveras, E. M., Camargo, C. A., Rifas-Shiman, S. L., Oken, E., Gold, D. R., Weiss, S. T. and Gillman, M. W. (2006), Association of birth weight with asthma-related outcomes at age 2 years. Pediatr. Pulmonol., 41: 643–648. doi: 10.1002/ppul.20427
- Issue online: 25 MAY 2006
- Version of Record online: 15 MAY 2006
- Manuscript Accepted: 24 FEB 2006
- Manuscript Revised: 20 FEB 2006
- Manuscript Received: 6 DEC 2005
- US National Institutes of Health. Grant Numbers: HD 34568, HL 64925, HL 68041
- EM Taveras is supported in part by the Minority Medical Faculty Development Program of the Robert Wood Johnson Foundation
- birth weight;
- fetal growth;
- length of gestation;
Although lower birth weight associated with prematurity raises the risk of asthma in childhood, few prospective studies have examined higher birth weight, and few have separated the two components of birth weight, fetal growth and length of gestation.
To examine the associations of fetal growth and length of gestation with asthma-related outcomes by age 2 years.
We studied 1,372 infants and toddlers born after 34 weeks' gestation in Project Viva, a prospective cohort study of pregnant mothers and their children. The main outcome measures were parent report of (1) any wheezing (or whistling in the chest) from birth to age 2 years, (2) recurrent wheezing during the first 2 years of life, and (3) doctor's diagnosis of asthma, wheeze or reactive airway disease (“asthma”) by age 2. We calculated gestational age from the last menstrual period or ultrasound examination, and determined birth weight for gestational age z-value (“fetal growth”) using US national reference data.
Infants' mean birth weight was 3,527 (SD, 517; range, 1,559–5,528) grams. By age 2 years, 34% of children had any wheezing, 14% had recurrent wheezing, and 16% had doctor-diagnosed asthma. After adjusting for several parent, child, and household characteristics in logistic regression models, we found that infants with birth weight ≥4,000 g were not more likely to have any wheezing (odds ratio (OR), 0.91; 95% confidence interval (CI): 0.62, 1.34) or doctor-diagnosed asthma (OR, 0.80; 95% CI: 0.49, 1.31) than infants with birth weight 3,500–3,999 g. In models examining length of gestation and fetal growth separately, neither the highest nor the lowest groups of either predictor were associated with the three outcomes. Boys had a higher incidence of asthma-related outcomes than girls, and exposure to passive smoking, parental history of asthma, and exposure to older siblings were all associated with greater risk of recurrent wheeze or asthma-related outcomes at age 2 years.
Although male sex, exposure to smoking, parental history of asthma, and exposure to older siblings were associated with increased risk of wheezing and asthma-related outcomes in this prospective study of children born after 34 weeks gestation, fetal growth and length of gestation were not. Pediatr Pulmonol. 2006; 41: 643–648. © 2006 Wiley-Liss, Inc.