Bottom Line: A breastfeeding program appeared to reduce the development of atopic eczema (an allergic skin response) but not asthma and lung function among children at age 16.
Why The Research Is Interesting: Many health organizations recommend exclusive breastfeeding to prevent atopic eczema and asthma but recommendations are mostly based on observational study evidence.
Who: 13,557 adolescents born 16 years prior to new mothers participating in a trial of a breastfeeding promotion in Belarusian maternity hospitals and affiliated clinics in Belarus.
When: The initial breastfeeding promotion intervention trial was June 1995 through 1997; follow-up of children from September 2012 to July 2015; data analysis from May 2016 to April 2017
What (Study Measures): Breastfeeding (exposure); at age 16, the adolescents were physically examined for atopic eczema around the eyes, neck, elbows, knees and ankles; spirometry measured lung function; and children self-reported their atopic eczema and asthma symptoms in the past year on questionnaires (outcomes). You can learn more about atopic diseases in children at this JAMA Pediatrics Patient Page.
How (Study Design): This is a long-term follow-up of children who participated in a cluster randomized trial that paired maternity hospitals and clinics to compare the effects of a breastfeeding intervention on children's health with standard care. Randomized clinical trials (RCTs) allow for the strongest inferences to be made about the true effect of an intervention. However, not all RCT results can be replicated in real-world settings because patient characteristics or other variables may differ from those that were studied in the RCT, and many exposures that were not part of the trial may occur naturally in clinical care or real life after the trial is completed that could explain the study findings.
Authors: Carsten Flohr, M.D., Ph.D., of King's College London and Guy's & St. Thomas' National Health Service (NHS) Foundation Trust, London, and coauthors
Results: Of the 7,064 children in the breastfeeding intervention group, 21 (0.3 percent) had signs of atopic eczema when their skin was examined at the 16-year follow-up compared with 43 of 6,493 (0.7 percent) children in the control group.There was no significant difference in lung function or asthma diagnoses between the 2 groups.
Study Limitations: Generalizability of the results is limited because Belarus has a highly centralized health care system, which made implementation of the breastfeeding intervention easier. Also, atopic eczema and allergic diseases overall are less common in Belarus compared to more affluent country setting, such as Western Europe or North America.
Study Conclusions: An intervention that promoted prolonged and exclusive breastfeeding of infants was associated with reduced risk of atopic eczema in adolescents but appeared to have no protective effect on lung function and asthma.
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