Abstract
Introduction
Published studies on breastfeeding (BF) and infant respiratory infections are inconclusive, suggesting either protective effects of BF or no protection. Many studies assessed general upper or lower respiratory tract infections, only one infection at a time or did not control for confounding. This study estimates the association of BF and various respiratory infections in infants controlling for relevant confounders.
Methods
We analysed parent-reported questionnaire data of 1-year-olds from a population-based cohort in Leicestershire, UK. BF duration(0,<=3mo,4-6mo,>6mo), ear infections, frequent colds(>4 times during last 12 months), pneumonia, whooping cough, bronchiolitis, croup, other chest and throat infections were assessed in 1998. We used multivariable logistic regression to estimate the association of BF and infections controlling for socio-demographic, prenatal, perinatal and environmental confounders.
Results
Among 4246 infants whose parents replied in 1998(response rate 79%), 58% were breastfed. The most prevalent infections were frequent colds(54%) and ear infections(42%), followed by throat infections, croup, chest infections and bronchiolitis(reported by 6-11%); whooping cough and pneumonia were rare(2% and 1% respectively). We found negative associations between BF and whooping cough(OR 0.5, 95%CI 0.2-1.0) or bronchiolitis(0.7, 0.5-0.9), but positive association between BF and frequent colds(1.3, 1.1-1.7).
Conclusion
The association between BF and respiratory infections seems to differ by type of disease. Future studies should have a prospective design with continuous assessment of BF and respiratory infections.
Funding:
SNF PDFMP3 137033; SNF32003B-144068; Asthma UK 07/048; CSC201308340039.
- © 2014 ERS
