A recent study conducted in The Netherlands examined the association between breastfeeding a baby in infancy and the development of asthma-related symptoms, such as wheezing, coughing and shortness of breath, in childhood. They assessed the duration, as well as exclusiveness of breastfeeding and its effect on the incidence of asthma. The study found that children who were not breastfed for at least six months were at a higher risk for developing asthma-related symptoms like wheezing, coughing, shortness of breath and persistent phlegm during their first four years. These symptoms were not frequently observed in those who were breastfed for more than six months.
Children with asthma often have symptoms such as wheezing, breathlessness and coughing. Asthma is a major cause of distress in children. Several factors, such as day care attendance, low birth weight, existence of siblings and family history of asthma, are found to be associated with asthma-related symptoms. There have been many studies conducted to explore the role of breastfeeding in relation to incidence of asthma. However, these studies have shown inconsistent results. Moreover, most of these studies were done on schoolchildren and the data on breastfeeding was obtained through recall, which is subject to bias. In the present study, children were followed, from fetus to four years of age, to assess the duration of breastfeeding and the occurrence of asthma-related symptoms in them.
* In this study, 7,295 children were included, out of which data on only 5,368 children was available for analysis.
* Information on the beginning and continuation of breastfeeding was collected using questionnaires. These questionnaires were mailed to the parents when their children became 2, 6 and 12 months of age. Data regarding the exclusiveness of breastfeeding and the use of milk solids and other alternatives was also collected in the same questionnaire.
* Information on asthma-related symptoms was collected every year until the children turned four years old. Information on respiratory infections, if any, skin rashes and itching (a sign of allergies), was gathered to determine the possible reasons for the development of asthma.
* About 92 percent of the children were breastfed; and the average period of breastfeeding was 3.5 months. Only 21 percent of these were exclusively breastfed until 4 months of age.
* The risk of developing symptoms of asthma, such as wheezing, dry cough, excessive phlegm and shortness of breath was high in those who were never breastfed, compared to those who were breastfed for more than six months.
* Those children who were non-exclusively breastfed (they were fed with milk solids and other alternatives) had more chances of developing asthma-related symptoms until four years of age, compared to those who were breastfed exclusively.
* Among the various symptoms of asthma, wheezing and persistent phlegm were found to be the most prevalent.
In the present study, only those symptoms that were related to asthma were evaluated. These symptoms may have been due to other respiratory disorders. Moreover, the study was exclusively based on questionnaires. Future studies must collect data that are more objective by performing tests such as lung function tests and bronchial responsiveness tests. Future studies must try to identify the cause for increased occurrence of asthma in non-breastfed children.
Prior studies have shown the effect of the duration and exclusiveness of breastfeeding on the risk of asthma. These studies have indicated that the risk of developing asthma from the age of 2 to 6 years is 2.22 times higher in those who are not breastfed until the age of 4 months. The present study has not only reiterated the findings of these studies, but has also shown the relationship between the duration of breastfeeding and the number of wheezing episodes. The strength of the present study is that a large number of participants were involved. According to researchers, there is a growth of various resident microbes in the gut of children who are fed a formula diet, which makes them prone to frequent infections and asthma. The authors conclude saying, “Our results suggest that a short duration of breastfeeding and non-exclusivity are associated with increased risk of the asthma-related symptoms during the first four years of life.”
For More Information:
Duration and Exclusiveness of Breastfeeding and Childhood Asthma-Related Symptoms
Publication Journal: European Respiratory Journal, July 2011
By Agnes M. M. Sonnenschein-van der Voort; Vincent V. W. Jaddoe, MD, PhD; Erasmus Medical Center, Rotterdam, The Netherlands