January 26, 2021

expert reaction to study looking at neonatal antibiotics and growth and BMI in children

A study published in Nature Communications looks at whether neonatal antibiotic exposure affects child growth during first six years of life.

Prof Rod Mitchell, Professor of Developmental Endocrinology, MRC Centre for Reproductive Health, University of Edinburgh, and Consultant Paediatric Endocrinologist, Royal Hospital for Sick Children, Edinburgh, said:

“This well conducted study involving more than 12000 children identified an association with antibiotic use in the neonatal period and a reduction in height and weight of boys over the first 6 years of life.

“Importantly, the study confirmed this association in a second independent population of 1707 children.

“The authors also conducted a study in mice which suggested that any effects on growth could be due to the antibiotic changing the composition of the microbiome in the gut.

“Whilst the study demonstrated an association between neonatal antibiotic use and reduced height in children at 6 years, it is important to recognise that final adult height is also strongly influenced by growth during puberty.

“Extended follow-up studies are required to determine whether early antibiotic exposure is associated with persistent alterations on growth parameters or growth-related health problems.

“It should be emphasised that infection is a leading cause of neonatal death worldwide and antibiotics are critical for the prevention and treatment of infection during this period.”

Dr Lindsay Hall, Microbiome Group Leader & Wellcome Investigator, Quadram Institute Bioscience, said:

“Infants and children are often prescribed antibiotics to treat infections and this study by Uzan-Yulzari and colleagues provides further evidence that this antibiotic exposure – particularly during the early life window, may impact developing microbial communities within the gut.

“What is interesting about this study is the team looked both when the children were young and then older and found that in the neonatal window both weight gain and height were reduced after antibiotic exposure – but only in boys (which they tested in animal models by giving them a faecal transplant).  Older children – both girls and boys were then found to have a higher BMI, suggesting a complex relationship between antibiotic use and child development and metabolism.

“In a small group of the infants they also looked at the types of bacteria that might be impacted by antibiotics and found that the beneficial group, Bifidobacterium, seemed to be more negatively impacted than other types.

“This study opens up new avenues for investigating how antibiotics during infancy may alter the microbiome.

“The results must be interpreted carefully as it was unselected group of infants and many daily factors may influence height and weight – like diet, which was not explored in detail in this study.

“They also only analysed a relatively small number in detail by looking specifically at their microbiome.  More clinical studies and lab experiments are needed to understand how and why microbes like Bifidobacterium may be positively impacting early growth and development during early life.”

‘Neonatal antibiotic exposure impairs child growth during the first six years of life by perturbing intestinal microbial colonization’ by Atara Uzan-Yulzari et al. was published in Nature Communications at 16:00 UK time on Tuesday 26 January 2021.

DOI: 10.1038/s41467-020-20495-4

Declared interests

Prof Rod Mitchell: “None.”

Dr Lindsay Hall: “No conflicts.”