Long-term effects on growth of an energy-enhanced parenteral nutrition in preterm newborn: a quasi-experimental study

Aim To assess the best energy intake in Parenteral Nutrition (PN) for preterm newborns, considering both possible benefits for growth and risk of complications. Methods Quasi-experimental study comparing two cohorts of newborns, receiving Energy-Enhanced vs. Standard PN (Cohort A, from 1st January 2015 to 31 January 2016 and Cohort B from 1st February 2016 to 31 March 2017; respectively) after implementation of a change in the PN protocol. The primary outcome measure was growth at 24 months of life. The PN associated complications were also measured. Results We enrolled 132 newborns in two Cohorts, similar for prenatal and postnatal clinical characteristics. Although, body weight and length at 24 months of life were significantly higher (p<0.05) in the Cohort A (11.1, 95% CI 10.6 to 11.6 Kg; 85.0 95% CI 83.8 to 86.2 cm) compared with Cohort B (10.4, 95% CI 9.9 to 10.9 Kg; 81.3 95% CI 79.7 to 82.8 cm), body weight and length Z-Score in the first 24 months of life were similar between the two Cohorts. The rate of PN associated complications was very high in both study Cohorts (up to 98% of enrolments). Multivariate analysis showed that length at 24 months was significantly associated with receiving standard PN (cohort A) in the first week of life and on the energy intake in the first week of life. We also found a marginally insignificant association between Cohort A assignment and body weight at 24 months of life (p = 0.060). Conclusions Energy-enhanced PN in early life has not significant effects on long-term growth in preterm newborns. The high prevalence of PN associated complications, poses concerns about the utility of high energy intake recommended by current guidelines for PN.