P0783 - Smaller Feeding Bottle Size in Newborns Reduces Overfeeding on First Day of Life which is a Risk Factor for Later Life Overweight and Obesity

Background/Purpose
The prevalence of obesity among infants less than 2 years of age has increased 60% over the last 30 years. Obese infants and toddlers are at an increased risk for staying overweight. Metabolic programming in animal models has shown early life feeding habits having life-long changes in hormone balance and metabolism. Our previous research suggested that overfeeding as early as the first day of life (DOL1) is a risk factor for obesity. The current study extends this research by exploring the impact of smaller bottle size implemented at one academic center's newborn nursery on reducing overfeeding and subsequent increased BMI. We hypothesized that overfeeding as early as DOL1 is a risk factor for obesity later in childhood, and that smaller bottle sizes used in the newborn nursery can reduce this risk.

Methods
Retrospective chart data was collected from the EMR including formula feed volume data on DOL1 as well as BMI data through age 5. Confounding factors such as birth weight, delivery type, gender, and race were controlled for. Literature review was used to define an overfeed as a single feed > 30mL. In 2012, the newborn nursery switched from 60mL bottles to smaller bottles able to hold a maximum volume of 10mL (which closely reflects the physiologic capacity of the newborn stomach). Statistical analysis was performed to determine if smaller bottle size reduced overfeeding practices and subsequent risk of becoming obese.

Results
5183 infants were analyzed, including pre and post intervention infants. In the subset of infants overfed every feed on DOL1, there was an 8.5x increased risk of presenting to their 4th or 5th year well child visit as overweight or obese. Those overfed 2 or more times on DOL1 there was a 1.7x increased risk of overweight or obesity at 4 years of age (p=.01). The average feed volume on DOL1 before bottle size reduction was 22.6mL, while average feed volume after this intervention was 16.1mL (p<0.001). 41 percent of newborns born before implementation of smaller feeding bottle size were overfed 3 or more times on DOL1 while only 16% of those born after the intervention were overfed 3 or more times on DOL1 (p<0.0001).

Conclusion
In our study, infants who were overfed on DOL1 were significantly more likely to present at their 4th year well child visit as overweight or obese, compared to infants not overfed on DOL1. Utilization of a smaller bottle size significantly reduced average feed volume. The present study suggests that smaller feeding volumes encouraged by smaller newborn nursery bottle size can have a positive impact on childhood obesity.