The level of extracellular superoxide dismutase in the first week of life in very and extremely low birth weight infants and the risk of developing bronchopulmonary dysplasia

Background: Antioxidant enzymes may play a significant role in the development of bronchopulmonary dysplasia (BPD). The aim of the study was to assess the relationship between the level of extracellular superoxide dismutase (SOD3) in the serum at days 1 and 7 of life and the risk of developing BPD. Methods: The study comprised 103 neonates born before 32 weeks' gestation with a birth weight of <= 1500 g. Results: In the investigated group, the median serum SOD3 level at day 1 of life was 4.01 ng/mL [interquartile range (IQR) 2.59-5.09 ng/mL] and at day 7 of life 3.13 ng/mL (IQR 2.49-4.34 ng/mL). A statistically significant decrease in the serum SOD3 level was found in the first week of life, P <0.0001. No correlation was found between the serum SOD3 level at day 1 of life and gestational age R=0.07, P=0.4543 and birth weight R=0.10, P=0.3083. No statistically significant correlation was found between the dynamics of change in the SOD3 level in serum at days 1 and 7 of life and the risk of BPD development for the definition of BPD at day 28 of life, P=0.8764 nor at 36 weeks' postmenstrual age, P=0.6598. Conclusion: The study revealed a statistically significant decrease in the serum SOD3 level in the first week of life in very and extremely low birth weight infants born before 32 weeks of gestation. In the clinical setting, no relationship was observed between the level of SOD3 in serum and the risk of developing BPD.