title: Blood transfusion. Iron load and retinopathy of prematurity.
abstract: To study the relationship between blood transfusion, iron load and retinopathy of prematurity (ROP), we performed a prospective observational cohort study in a level III neonatal intensive care unit. During a 24-month period, data on the volume of blood transfused during the first 6 weeks of life and on the incidence of ROP were collected in all surviving very low birth weight infants (n = 114; median birth weight 1130 g. range 520-1500 g). Associations between these data and values for serum iron, transferrin and ferritin measured at weekly intervals were analysed in a nested case-control design by logistic regression. There was a significant association between the volume of blood transfused and the incidence of ROP. After adjustment for gestational age at birth, duration of oxygen therapy (FiO2 > 0.3) and duration of mechanical ventilation, the relative risk of developing ROP was 6.4 (95% CI 1.2-33.4) for infants who had received 16-45 ml/kg, and 12.3 (1.6-92.5) for those who had received more than 45 ml/kg of blood (reference, 0-15 ml/kg). In contrast, there was no independent relationship between ROP and any of the parameters on iron metabolism analysed.
  
  
  CONCLUSIONS
  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.
authors.affiliation: Department of Ophthalmology, Philipps-University, Marburg, Germany.
authors.forename: L
authors.initials: L
authors.lastname: Hesse
authors.forename: W
authors.initials: W
authors.lastname: Eberl
authors.forename: M
authors.initials: M
authors.lastname: Schlaud
authors.forename: C F
authors.initials: CF
authors.lastname: Poets
mesh_terms: D016022:Case-Control Studies; D005293:Ferritins / Q000097:blood; D005858:Germany / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D007231:Infant, Newborn; D007234:Infant, Premature; D019102:Infant, Very Low Birth Weight; D007363:Intensive Care Units, Neonatal; D007501:Iron / Q000378:metabolism*; D016015:Logistic Models; D015999:Multivariate Analysis; D016017:Odds Ratio; D011446:Prospective Studies; D012178:Retinopathy of Prematurity / Q000453:epidemiology*; D012307:Risk Factors; D065227:Transfusion Reaction
chemical_list: D005293:Ferritins; D007501:Iron