by Anne Eglash MD, IBCLC, FABM
Does a breastfeeding infant have a lower risk of respiratory tract infections after weaning?
A large study in the Netherlands known as the R Generation Study has been tracking nearly 8000 individuals from fetal life to adulthood. The researchers collected breastfeeding information on 5322 children who have been participating in this study, and asked their parents about their child’s rate of upper and lower respiratory infection at the ages of 2,3, and 4 years of age. An upper respiratory infection was defined as a serious cold, ear infection or throat infection. A lower respiratory infection was defined as pneumonia or bronchitis. The researchers controlled for many other reasons for respiratory infections such as smokers in the home, daycare, family income, number of siblings, etc.
What do you think the authors concluded about the relationship between breastfeeding and respiratory infections (choose 1 or more):
- Infants who breastfeed for less than 3 months have a lower risk of colds and ear infections at ages 2,3, and 4.
- Infants who breastfeed between 3-6 months have a lower risk of pneumonia and bronchitis at ages 2, 3 and 4.
- Infants who breastfeed for 6 months or longer have a lower risk of pneumonia and bronchitis at ages 2,3, and 4.
- Infants who breastfeed for 6 months or longer have a lower risk of colds and ear infections at ages 2,3, and 4.
See the Answer
The answer is C
Breastfeeding and the risk of respiratory tract infections after infancy: The Generation R Study
Ilse Tromp, Jessica Kiefte-de Jong , Hein Raat, Vincent Jaddoe, Oscar Franco, Albert Hofman
Published: February 23, 2017
Background
The protection of breastfeeding against respiratory tract infections in the first year of life has often been suggested. Few studies examined the effect of breastfeeding on respiratory tract infections after infancy.
Objective
To examine the association between breastfeeding with lower respiratory tract infections (LRTI) and upper respiratory tract infections (URTI) after infancy up to 4 years of age (n = 5322).
Methods
This study was embedded in The Generation R study, a Dutch population-based prospective cohort study from fetal life until young adulthood. Information on breastfeeding duration (never; <3 months; 3–6 months; ≥6 months) and dose (never; partially until 4 months; predominantly until 4 months) were collected by questionnaire at 2, 6, and 12 months of age. Information on doctor attendance for LRTI and URTI were obtained by questionnaire at 2, 3, and 4 years of age.
Results
Breastfeeding for 6 months or longer was significantly associated with a reduced risk of LRTI up to 4 years of age (aOR: 0.71; 95% CI: 0.51–0.98). Similar ORs for LRTI were found with breastfeeding for less than 3 months and 3–6 months. Although in the same direction, weaker ORs were found for URTI and breastfeeding duration. The same trend was found for partial and predominant breastfeeding until 4 months and LRTI and URTI.
Conclusion
Breastfeeding duration for 6 months or longer is associated with a reduced risk of LRTI in pre-school children. These findings are compatible with the hypothesis that the protective effect of breastfeeding for respiratory tract infections persist after infancy therefore supporting current recommendations for breastfeeding for at least 6 months.
Milk Mob Comment by Anne Eglash MD, IBCLC, FABM
This study demonstrated that infants who breastfeed for 6 months or longer have a lower risk of pneumonia and bronchitis at the ages of 2,3, and 4 years of age. However, infants who breastfeed for 6 months or longer don’t appear to have a significantly lower rate of ear infections and colds at ages 2,3 and 4. Infants who breastfeed for less than 6 months don’t benefit from lower rates of pneumonia or bronchitis when they are older.
So what is going on? We know that breastmilk provides antibodies and other factors to help infants fight infection, so that their illnesses are not as severe. The bioactive factors in breastmilk also help mature the infant’s immune system, such that after weaning, the child is better equipped to handle serious infections as compared to children who didn’t receive breastmilk for at least 6 months.
I am not surprised that there was no significant difference in upper respiratory infections, such as colds or ear infections at ages 2,3, and 4 among children who were breastfed less than 6 months vs longer than 6 months. The authors pooled colds and ear infections together, so we really don’t know if the infants who nursed for 6 months or longer had fewer ear infections at ages 2,3, and 4. Based on my experience, a cold is simply a common cold. I don’t see a difference in the rate of colds in my breastfeeding vs formula feeding pediatric patients. However, what I do notice is that the children who were breastfed for longer periods of time seem less likely to develop pneumonia as a complication of a cold, as compared to children who were never breastfed.
This is a strong study because of the number of participants, and because the researchers made sure to take out the variables that can be associated with respiratory infections.
When infants are seen during well-child exams or for illness visits, we ought to share these findings with families, to encourage them to continue breastfeeding for at least 6 months.