To evaluate dietary protein's effect on fat accretion and weight gain in hospitalized preterm infants.
Prospective, randomized, double-blind, controlled trial of 36 infants born at <32 weeks, hospitalized in a tertiary NICU. After achieving full enteral volume, infants were randomized to either an enhanced protein diet (EPD) (protein-energy ratio [PER] 4 g/100 calories) or a standard protein diet (SPD) (PER 3 g/100 calories). Macronutrients were calculated using published values for formula, donor milk bank analysis, or weekly analysis of a 24-hour pooled maternal milk sample. Human milk fortifier and/or liquid protein were used to achieve the target PER until discharge or a maximum of 4 weeks. Body composition was measured weekly using air displacement plethysmography. The principal outcomes, rates of weight gain and fat accretion, were compared between groups in linear mixed models.
Thirty-three infants received approximately 17 days of the study diet. Relative weight gain was 21.6 g · kg−1 · day−1 (95% confidence interval [CI] 19.5–23.8) for the EPD group (n = 16) versus 19.1 g · kg−1 · day−1 (95% CI 17.0–21.2) for the SPD group (n = 17), P = 0.095. Baseline percent fat mass (FM) in the EPD group was 5.15% (95% CI 3.58%–6.72%) compared with 7.29% (95% CI 5.73%–8.84%) in the SPD group, P = 0.0517. Percent FM increased 0.398%/day (95% CI 0.308–0.488) for the EPD group versus 0.284%/day (95% CI 0.190–0.379) for the SPD group (P = 0.0878).
Preterm infants with a lower baseline FM percentage who received an EPD demonstrated a more pronounced catch-up percentage of fat accretion.
*Neonatal-Perinatal Medicine, University of Oklahoma Health Sciences Center
†Food and Nutrition Services, University of Oklahoma Children's Hospital, Oklahoma City
‡Biostatistics and Epidemiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK.
Address correspondence and reprint requests to Courtney B. Atchley, DO, Neonatal-Perinatal Medicine, University of Oklahoma Health Sciences Center, 1200 Everett Drive, ETNP 7504, 7th Floor North Pavilion, Oklahoma City, OK 73104 (e-mail: firstname.lastname@example.org).
Received 25 September, 2018
Accepted 14 March, 2019
This study was supported by the University of Oklahoma Health Sciences Center Section of Neonatal-Perinatal Medicine's Research Section Grant program.
The study was registered with ClinicalTrials.gov (NCT02353013) at the University of Oklahoma Health Sciences Center.
The authors report no conflicts of interest.
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