An Observational Study on Effect of High Human Milk Intake on Oxidative Status of VLBW Infants

Abstract

Background: Preterm infants are at high risk of oxidative stress injuries from various conditions such as low antioxidant capacity, relatively hyperoxia state outside utero, and possible immaturity of many organs. Human milk is an ideal nutrition and medication for these infants. It has antioxidative effects from both enzymatic and non-enzymatic constituents. Objective: To evaluate the beneficial effects of human milk on oxidative status and antioxidant capacity in very-low birth weight infants. Materials and Methods: The present research was a prospective cohort study conducted between January and December 2017. Preterm birthweight less than 1,500 grams were enrolled. Infants were divided into two groups based on breastmilk intake proportion, more than 50% or less than 50% of milk intake. Oxidative status was assessed using plasma malondialdehyde (MDA), and total antioxidant status (TAS) was assessed using Trolox equivalent antioxidant capacity (TEAC). Results: Nineteen (19) VLBW infants were enrolled. Six infants (32%) were in low breastmilk intake group and 13 infants (68%) received breastmilk 50% or more of total enteral intake. Plasma MDA at D1, D7, and D28 were 6.49±5.76, 9.49±6.77, and 6.96±4.84 μM in the low breastmilk intake group, and 8.68±4.44, 8.82±5.01, and 5.71±2.74 in the high breastmilk intake group (p>0.05). Plasma TAS at D1, D7, and D28 were 4.06±0.87, 6.73±2.07, and 7.59±2.03 mmol of Trolox equivalence/L in the low breastmilk intake group, and 8.2±1.55, 7.4±2.29, and 6.58±1.9 mmol of Trolox equivalence/L in the high breastmilk intake group (p>0.05). There was no difference in patient characteristics regarding gender, gestational age, birthweight, mode of delivery, surfactant use, duration of mechanical ventilation, or duration of oxygen supplementation. Conclusion: The present study was unable to demonstrate the differences of plasma MDA and total antioxidant capacity in VLBW infants. Therefore, further studies using more sensitive markers were suggested. Keywords: VLBW, Very low birth weight, Preterm, Oxidative stress, Human milk