Short- and Long-term Effects of Antibiotics on Childhood Growth

Background and Significance: Antibiotics are among the most valuable medical discoveries. Recent research on understanding of how bacteria in our gut use energy, however, raises concerns about whether broad-spectrum antibiotics, which are overprescribed for mild infections, prescribed in early infancy may cause obesity during childhood. Obesity is a very common and serious condition among US children, particularly children from disadvantaged populations. Yet those studies are too small and they lack diversity as well as modern scientific tools to gauge the extent to which prescribing antibiotics can lead to excess weight gain. PCORnet, the National Patient-Centered Clinical Research Network, comprising very large networks of data from electronic medical records, provides an ideal test bed to address this question. Further, it is not clear how caregivers and clinicians will use the results of earlier studies to decide which antibiotics to prescribe when faced with common infections like ear infections.

Specific Aims: The objectives of the proposed study are to assess the effects of different types, timing, and amount of antibiotic use in the first two years of life with (Specific Aim 1) body mass index (BMI) and obesity at ages 5 and 10 years and (Specific Aim 2) growth trajectories to age 5 years. In Specific Aim 3, we will address how big the effects of antibiotics on obesity are within subgroups of the population, such as different racial/ethnic groups and whether the child’s mother got antibiotics while she was pregnant.

Data Sources and Infrastructure: The data for this study will come from electronic medical records of about 1.6 million children from 42 healthcare systems within 9 Clinical Data Research Networks across the United States. We will get information on antibiotic prescribing in the first two years of life, then “virtually” follow these children to ages 5 and 10 years to see what their BMIs are, and how many of them are obese by clinical standards (i.e., heavier than 95 percent of children of the same age and sex.

In the main analyses, the CDRNs will not send any individual data to a central site. Rather, using sophisticated computer programs, the coordinating center will send “questions to the data,” thus protecting the privacy of patients’ and the healthcare systems’ records. In some analyses, to check how well this “distributed research network” approach works, we will work with individual records whose identifying information has been stripped off (“de-identified data”).

Stakeholder Engagement: In our Secondary Aim, we will employ focus groups of parents and in-depth interviews of clinicians to explore how best to put the findings into everyday practice.

Throughout, in addition to employing privacy-protecting approaches to analyzing and sharing data, we will adhere to principles of inclusion, patient-centeredness, stakeholder engagement, effective governance, and protection of human subjects. At the end of the two-year project, we will propose avenues for dissemination of the scientific findings and other products.

Health Services Research Projects in Progress (HSRProj) Registration Registration

PCORI Award Information