Blood Transfusion, Iron Load, and Retinopathy of Prematurity. 198

Abstract

Background. To study the relationship between blood transfusion, iron load and retinopathy of prematurity (ROP). Setting: Prospective observational study in a level III neonatal intensive care unit. Methods. During a 24 month period, serum iron, transferrin and ferritin levels were measured during the first 8 weeks of life in 114 sequentially admitted very low birth weight infants (median birth weight 1130 g, range 520-1500g). These data were related to the volume of blood transfused and to the incidence of ROP, using logistic regression analysis. Results. There was a significant association between the volume of blood transfused and the incidence of ROP. After adjustment for gestational age at birth and duration of oxygen therapy (FiO2>0.3), the relative risk of developing ROP was 6.9 (95% CI 1.3-35.2) for infants who had received 16-45 ml/kg of blood and 17.3 (2.7-109.8) for those who had received more than 45 ml/kg (reference, 0-15 ml/kg). In contrast, there was no independent relationship between ROP and any of the parameters on iron metabolism analysed. Conclusion. This study confirms the role of blood transfusions as an independent risk factor for ROP. This relationship, however, does not appear to be mediated via an increased iron load.