Abstract
Background/objective
Literature shows a positive association between antibiotics and obesity in childhood, but fails to account for confounding by indication. We evaluate the direct effect of infection on obesity and the indirect effect mediated by antibiotics by performing a mediation analysis of the infection-obesity association.
Methods
A Medicaid cohort of children age 2–14 years old between 2015–2019 (n = 61,330) is used to perform mediation analysis of infections and antibiotic use in the first year of life, and obesity in childhood in Missouri, U.S.A.
Results
An additional infection increases the risk of obesity in childhood (aIRR = 1.050, p < 0.001); however, mediation by antibiotic use is clinically and statistically insignificant. If the number of infections is not considered in the analysis, then antibiotic use as a risk factor for obesity is overstated (aIRR = 1.037 vs. 1.013 p < 0.001).
Conclusions
The number of infections exhibits a significant relationship with obesity and is a stronger risk factor for obesity than antibiotic use. In particular, a greater number of bronchitis, otitis media, and upper respiratory infections in the first year of life are associated with a significant increased risk of obesity in childhood. We find only weak evidence that an additional antibiotics claim increases the risk of obesity in childhood and this risk may not be clinically meaningful. Further research is needed to explore the association between early childhood infections, especially in the first 6 months of life, and obesity including the biological mechanism and environmental factor of early life infections associated with obesity.
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Data availability
These data are not publicly available, but the deidentified cohort was acquired with permission from the Missouri Department of Social Services, through partnership with the Center for Health Policy at the University of Missouri. Due to confidentiality agreements, supporting data can only be made available to bona fide researchers subject to a non-disclosure agreement. Details of the data and how to request access are available through the Center for Health Policy at the University of Missouri in partnership with the Missouri Department of Social Services where the data reside.
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Acknowledgements
We thank the Center for Health Policy for providing tremendous support in requesting, accessing, and approval of the use of this data from the Missouri Department of Social Services. We also thank participants at the MU-Collaborative Health Researchers Interdisciplinary Seminar Series for valuable feedback.
Funding
Funding for data acquisition for this research was supported by the MU-Child Health Research Institute through the Lead J. Sears Grant Award.
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AMO conceived of the hypothesis and carried out the data acquisition, analysis, generation of figures and tables, and initial manuscript. AM provided clinical expertise, literature search, interpretation of findings, and manuscript editing. All authors were involved in writing the paper and had final approval of the submitted and published versions.
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Ohler, A.M., Braddock, A. Infections and antibiotic use in early life, and obesity in early childhood: a mediation analysis. Int J Obes 46, 1608–1614 (2022). https://doi.org/10.1038/s41366-022-01155-7
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DOI: https://doi.org/10.1038/s41366-022-01155-7