Improving long-term health outcomes of preterm infants: how to implement the findings of nutritional intervention studies into daily clinical practice

Abstract

Preterm-born children are at risk for later neurodevelopmental problems and cardiometabolic diseases; early-life growth restriction and suboptimal neonatal nutrition have been recognized as risk factors. Prevention of these long-term sequelae has been the focus of intervention studies. High supplies of protein and energy during the first weeks of life (i.e., energy > 100 kcal kg^-1 day^-1 and a protein-to-energy ratio > 3 g/100 kcal) were found to improve both early growth and later neurodevelopmental outcome. Discontinuation of this high-energy diet is advised beyond 32-34 weeks postconceptional age to prevent excess fat mass and possible later cardiometabolic diseases. After discharge, nutrition with a higher protein-to-energy ratio (i.e., > 2.5-3.0 g/100 kcal) may improve growth and body composition in the short term.Conclusion: Preterm infants in their first weeks of life require a high-protein high-energy diet, starting shortly after birth. Subsequent adjustments in nutritional composition, aimed at achieving optimal body composition and minimizing the long-term cardiometabolic risks without jeopardizing the developing brain, should be guided by the growth pattern. The long-term impact of this strategy needs to be studied. What is Known: • Preterm infants are at risk for nutritional deficiencies and extrauterine growth restriction. • Extrauterine growth restriction and suboptimal nutrition are risk factors for neurodevelopmental problems and cardiometabolic disease in later life. What is New: • Postnatally, a shorter duration of high-energy nutrition may prevent excess fat mass accretion and its associated cardiometabolic risks and an early switch to a protein-enriched diet should be considered from 32-34 weeks postconceptional age. • In case of formula feeding, re-evaluate the need for the continuation of a protein-enriched diet, based on the infant's growth pattern.

Keywords: Early nutrition; Postnatal growth restriction; Preterm birth; Protein-to-energy ratio.

Fig. 1

Recommendations for protein intake (a) and energy intake (b) from birth until 6 months corrected age represented as means with ranges (colored dotted lines) from parenteral (blue) and enteral (red) nutrition. Vertical dotted lines represent the “transition period” from 32 to 34 weeks postconceptional age to term age when energy intake may be (gradually) lowered to 115 kcal kg⁻¹ day⁻¹ with a protein intake of ≥ 3 g kg⁻¹ day⁻¹, provided that growth is age appropriate (i.e., 10–15 g kg⁻¹s day⁻¹ for at least 1 week) [45, 47]. Total protein intake from combined parenteral and enteral nutrition should not exceed 4.5 g kg⁻¹ day⁻¹; total energy intake from combined parenteral and enteral nutrition should not exceed 135 kcal kg⁻¹ day⁻¹

Fig. 2

Recommendations for the type of nutrition (colored horizontal lines) from birth until 6 months corrected age. Vertical dotted lines represent “transition periods” from 32 to 34 weeks postconceptional age to term age when energy intake may be (gradually) lowered to 115 kcal kg⁻¹ day⁻¹ with a protein intake of ≥ 3 g kg⁻¹ day⁻¹, provided that growth is age appropriate (i.e., 10–15 g kg⁻¹ day⁻¹ for at least 1 week) [45, 47]