Prolonged Breast-Feeding May Improve Subsequent Lung Function CME/CE
Prolonged Breast-Feeding May Improve Subsequent Lung Function CME/CE
News Author: Laurie Barclay, MD
CME Author: Charles Vega, MD, FAAFP
November 10, 2008 — Infants who received prolonged breast-feeding have improved lung function at age 10 years vs those who are not breast-fed, according to the results of a prospective birth cohort study reported in the November 10 Online First issue of Thorax.
“The protective effects of breastfeeding on early life respiratory infections are established, but there have been conflicting reports on protection from asthma in late childhood,” write U. Ogbuanu, from the Norman J. Arnold School of Public Health, University of South Carolina in Columbia, and colleagues. “The association of breastfeeding duration and lung function was assessed in 10-year-old children.”
At birth and at 1- and 2-year follow-up visits, breast-feeding practices and duration were prospectively evaluated in 1456 infants enrolled in the Isle of Wight birth cohort. Maternal history of asthma and allergy was determined at birth.
Of these 1456 infants, 196 were not breast-fed, 243 were breast-fed for less than 2 months, 142 for 2 to less than 4 months, and 374 infants were breast-fed for at least 4 months. At age 10 years, 1033 infants in the cohort underwent evaluation of lung function, reflected in measurements of forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), FEV1/FVC ratio, and peak expiratory flow (PEF).
After adjustment for birth weight, sex, current height and weight, family social status cluster, and maternal education, general linear models were used to determine the effect of breast-feeding on lung function.
Compared with infants who were not breast-fed, those who were breast-fed for at least 4 months had increased FVC by 54.0 ± 21.1 mL (P = .001), FEV1 by 39.5 ± 20.1 mL (P = .05), and PEF by 180.8 ± 66.1 mL/second (P = .006). The effect of breast-feeding was retained only for PEF in models for FEV1 and PEF that adjusted for FVC (P = .04).
“Breastfeeding for at least 4 months enhances lung volume in children,” the study authors write. “The effect on airflow appears to be mediated by lung volume changes. Future studies need to elucidate the mechanisms that drive this phenomenon.”
Limitations of this study include possible minimal selection bias and reporting bias and lack of clinical testing data for asthma and allergy in the mothers.
“Prolonged suckling at the breast compared with the bottle may convey a mechanical stimulus that results in improved mechanics of ventilation (due to physical training),” the study authors conclude. “Secondly, the presence of protective immunoactive factors in breast milk may reduce allergic susceptibility of the lung tissue.”
This study was funded in part by the National Institutes of Health, and the 10-year follow-up of this study was funded by National Asthma Campaign, United Kingdom. The study authors have disclosed no relevant financial relationships.
Thorax. Published online November 10, 2008.
