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Published on: September 19, 2019
The association between antibiotics in the first year of life and child growth trajectory
Elizabeth E Dawson-Hahn1,2, Kyung E Rhee3
1Department of Pediatrics, University of Washington, Seattle, WA, USA.
Insights
Early antibiotic exposure in infants may increase childhood obesity risk. Children receiving three or more antibiotic courses in their first year showed a significantly greater increase in BMI z-score by age six.
Area of Science:
- Pediatrics
- Environmental Health
- Epidemiology
Background:
- Antibiotic use in children is common and may influence obesity rates.
- Childhood obesity is a growing public health concern.
- The impact of early-life antibiotic exposure on growth requires further investigation.
Purpose of the Study:
- To investigate the association between antibiotic use in the first year of life and child growth trajectories.
- To analyze growth patterns from birth to age six, considering key covariates.
Main Methods:
- Utilized data from 586 children in the Infant Feeding Practices II (IFPS II) and 6-year follow-up study (6YFU).
- Employed linear mixed-effects growth modeling to assess antibiotic exposure effects on Body Mass Index z-score (BMIz) trajectories.
- Controlled for factors including breastfeeding, socio-demographics, and maternal health during pregnancy.
Main Results:
- 60.58% of infants received no antibiotics; 33.79% received 1-2 courses; 5.63% received 3+ courses in the first year.
- Children with 1-2 antibiotic courses showed a higher rate of BMIz change (0.17 higher).
- Children with 3+ antibiotic courses exhibited a significantly greater rate of BMIz change (0.42 higher, p=0.009) and overall growth trajectory (p=0.002) by age six.
Conclusions:
- Antibiotic exposure in the first year of life is associated with altered child growth trajectories, particularly increased BMIz.
- Findings underscore the importance of judicious antibiotic prescribing in early childhood.
- Further research and clinical guidance are needed to mitigate potential long-term health effects of early antibiotic exposure.
Background:
Antibiotics are frequently prescribed to children, and may be an environmental influence that contributes to the increasing prevalence of childhood obesity. The aim of this study was to examine the effect of antibiotic use in the first year of life on child growth trajectories from birth to age 6 years including significant covariates.
Methods:
Data from 586 children in the Infant Feeding Practices II (IFPS II) and 6 year follow-up study (6YFU) were included. Antibiotic exposures, weight and height measurements were collected from birth through the first 12 months, and then again at 6 years. Linear mixed effects growth modeling, controlling for exclusive breastfeeding, socio-demographic factors, smoking during pregnancy, gestational diabetes, and maternal pre-pregnancy weight status, was used to examine the association between antibiotic exposure and child growth trajectories through age 6 years.
Results:
The majority of infants (60.58%) did not receive any antibiotics; 33.79% received 1-2 courses and 5.63% received 3 or more antibiotic courses during the first year. In the unadjusted model, children with 1-2 antibiotic exposures had a 0.17 (SE 0.08) higher rate of change in BMI z-score (BMIz) than children without any antibiotics, and children with ≥3 exposures had a 0.42 (SE 0.16) higher rate of change in BMIz (p = 0.009). Growth trajectory over time for those who had ≥3 antibiotics was greater than those without any antibiotics (p = 0.002).
Conclusions:
Efforts to guide the judicious use of antibiotics should continue, particularly in the first year of life.
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