OBJECTIVETo study the effect of early protein and energy intake on early growth velocity of premature infants.

METHODSClinical data on premature infants with a birth weight of less than 1800 g were collected retrospectively, including records of general status, enteral and parenteral nutrition and growth parameters. These premature infants were divided into two groups according to the timing of amino acid administration: early supplementation (the first 24 hrs of life; EAA group; n=112) and late supplementation (after 24 hrs of life; LAA group; n=52). Protein and energy intake, protein/energy ratio and growth velocity during hospital stay were compared between the two groups. Correlation analysis was used to evaluate the association of early protein and energy intake and protein/energy ratio with growth velocity of infants.

RESULTSCompared with the LAA group, the EAA group presented lower weight loss (6.3% vs 8.8%), shorter time to return to birth weight (7 days vs 9 days), and higher head circumference growth (0.79 ± 0.25 cm/week vs 0.55 ± 0.25 cm/week) and weight growth velocity(20 ± 3 g/kg•d vs 17 ± 3 g/kg•d) (P<0.05). The correlation analysis indicated that protein and energy intake and protein/energy ratio on the 3rd and 7th days of life were positively correlated with weight growth velocity. The protein and energy intake per week after returning to birth weight was positively correlated with weight growth velocity (r= 0.709, P<0.01). Significant correlations were found between the protein and energy intake and both head circumference and length growth velocity on the 3rd and the 7th days of life.

CONCLUSIONSEarly administration of amino acids can reduce weight loss, shorten the time taken to return to birth weight, and increase weight and head circumference growth velocity in premature infants. An appropriate increase in protein intake can improve weight, circumference and length growth velocity.