Aims. Selenium (Se) deficient animals have increased susceptibility to oxidative lung injury. In preterm infants low blood Se levels have been documented and suggested as a potential risk factor for neonatal chronic lung disease. We aimed to study whether Se supplementation in very low birthweight infants (VLBW: B Wt <1500g) born in a country with low Se status was beneficial. Methods. In a blinded randomised controlled trial involving 8 New Zealand centres VLBW infants received Se (Se+) or placebo (P) from day 3 until 36 weeks corrected gestation or discharge home. Infants were stratified by centre and birthweight <1000g(ELBW) or =/>1000g. When on parenteral nutrition infants received 7μg/kg/d sodium selenate and when orally fed 5μg/kg/d sodium selenite or sterile water. Plasma Se was measured in mothers and in infants at 48hrs, 28 days and 36 wks corrected. Primary outcome measures were oxygen dependency at 28 days (CLD), 36 wks corrected (BPD), and days in oxygen.Results. There were 270 infants (118 ELBW) in Se+ (mean B Wt 1046g; Gest. 28.0 wks) and 262 (120 ELBW) in P (mean B Wt 1039g;Gest 27.8 wks). There were no significant differences between the groups in maternal age, antenatal steroids, C-section, 5 min Apgar <6, hyaline membrane disease, treated patent ductus, or deaths. Plasma Se (μmol/L) in mothers(Se+ 0.73, SE.02; P 0.71, SE.02) and infants at 48hrs (Se+ 0.33, SE.01; P 0.33, SE.01) were not different; but at 28 days (Se+ 0.57, SE.02; P 0.28, SE.01) were higher in Se+ infants (p<.0001). The incidence of CLD was 42.6% Se+ and 42.8% P (RR 0.995: 95% CI 0.82-1.21), of BPD was 34.7% Se+ and 31.8% P(RR 1.09: 95% CI 0.86-1.39), and mean days oxygen was 32.6 Se+ and 34.4 P. These differences were not significant. There were also no differences between groups on sub-group analysis (B Wt and centre).Conclusion. In a low Se status population, Se supplementation of VLBW infants with high doses Se (US recommended intake 1.5-3μg/kg/d) was not associated with lower rates of CLD, BPD or days oxygen dependancy.
