Anthropometrics and fat mass, but not fat-free mass, are compromised in infants requiring parenteral nutrition after neonatal intestinal surgery

Abstract

Background Children with intestinal failure (IF) receiving long-term parenteral nutrition (PN) have altered body composition (BC), but data on BC changes from start of PN onwards are lacking. Objective We aimed to assess growth and BC in infants after neonatal intestinal surgery necessitating PN and at risk for IF, and to explore associations with clinical parameters. Design Prospective cohort study in infants after intestinal surgery. IF was defined as PN-dependency for > 60 days. Standard deviation scores (SDS) for anthropometry were calculated until 6 months corrected age. In a subgroup, fat mass (FM) and fat-free mass (FFM) were measured with air-displacement plethysmography at 2- and 6-months corrected age. SDS for length-adjusted FM index and FFM index were calculated. Associations between cumulative amount of PN and BC parameters were analyzed with linear mixed-effect models. Results Ninety-five neonates were included (54% male, 35% born < 32 weeks). Thirty-nine infants (41%) had IF. Studied infants had compromised anthropometric parameters during follow-up. At 6 months corrected age, they remained smaller (median weight-for-age SDS –0.9 [interquartile range –1.5, 0.1], P < 0.001) than the normal population. In 57 infants, 93 BC measurements were performed. FM index SDS was lower than in healthy infants at 2- and 6-months corrected age (–0.9 [–1.6, –0.3], P < 0.001 and –0.7 [–1.3, 0.1], P = 0.001, respectively), but FFM index SDS did not differ. A higher cumulative amount of PN predicted higher FM index in female infants but lower FM index in male infants. Conclusions In this cohort of infants receiving PN after intestinal surgery, compromised anthropometrics, decreased FM and adequate FFM were observed during the first 6 months. Male and female infants seemed to respond differently to PN when it comes to FM index. Continuing growth monitoring after 6 months of age is strongly recommended, while further research should explore the benefit of incorporating ongoing BC monitoring during follow-up. Clinical Trial Registration: Dutch Trial Register NTR6080, https://www.trialregister.nl/trial/5892.