Poster Topical Area: Maternal, Perinatal and Pediatric Nutrition
Location: Hall D
Poster Board Number: 254
Objective: The objective of this prospective analysis was to determine the effect of growth velocity on the development of adipose tissue in very preterm infants. We studied the association between three categories of growth velocity and percent body fat (%BF) at 36 weeks of postmenstrual age (PMA).
Methods: Very preterm infants with gestational age (GA) ≤ 32 weeks at birth were included. Using the exponential method, we calculated growth velocity in all study participants and defined three categories (below target or < 10 g/kg/d, within target or 10 to 15 g/kg/d, and above target or > 15 g/kg/d). The primary outcome was %BF estimated by air displacement plethysmography at 36 weeks PMA.
Results: We assessed body composition in 86 infants (mean birthweight: 1445g, median GA: 30 weeks). The median growth velocity was 12 g/kg/d (IQR: 10 – 15) and the median %BF was 14.4 (IQR: 12.9 – 17.1). In an unadjusted regression analysis, there was no linear association between the three categories of growth velocity and %BF. In a regression analysis adjusted for birthweight, GA, sex, and weight Z-score at birth, the linear association between growth velocity and % BF was statistically significant (mean %BF in the group with growth velocity below target: 13.0±0.8; mean %BF in the group with growth velocity within target: 14.8±0.5; mean %BF in the group with growth velocity above target: 16.6±0.7; p=0.02). The group with growth velocity above target had higher weight Z-scores and higher %BF at 36 weeks PMA, but length Z-scores at 36 weeks PMA or hospital discharge did not differ across groups
Conclusion: By combining quantitative and qualitative outcomes of growth, we determined that growth velocity rates > 15 g/kg/d are associated with higher percent body fat at 36 weeks PMA in very preterm infants. Future research should investigate the value of growth velocity rates that increase %BF without achieving length differences and the impact of postnatal diets with different caloric densities and feeding volumes on quantitative and qualitative outcomes of growth.
Funding Source: None
University of Alabama at Birmingham