Lower Hemoglobin Levels as a Risk Factor for the Development of Retinopathy of Prematurity

Retinopathy of prematurity (ROP) is an important cause of visual morbidity among preterm infants. The objective of the study was to assess the relationship between the initial hematological parameters of the complete blood count (CBC) and ROP development in preterm neonates.

This retrospective cohort study was conducted in a neonatal intensive care unit in Odisha. The hematological parameters of the CBC conducted within the first 48 hours of age, demographic characteristics, neonatal morbidities, and ROP screening findings of preterm neonates (gestational age <34 weeks) were analyzed. Independent risk factors associated with ROP development were identified in a multivariate logistic regression model.

A total of 43 (29.1%) out of 148 neonates had any of the ROP stages (stage 1-26, 2-08, and 3-09). Birth weight (aOR 0.003; 95% CI 0.00, 0.11);hemoglobin (Hb) level (aOR 0.70; 95% CI 0.54, 0.90); presence of respiratory distress syndrome (RDS) (aOR 7.61; 95% CI 1.5, 36.39); and need for packed red blood cell (PRBC) transfusion (aOR 4.26; 95% CI 1.1, 16.44) were independently associated with ROP development. The odds of ROP were higher among the neonates with initial Hb 10.5-15.4 g/dL (OR (95% CI) 3.7(1.5, 8.9), p=0.003) and for neonates with Hb 15.4-17.3 g/dL (OR (95% CI) 2.5(1.01, 6.16), p=0.047) in comparison to neonates with initial Hb >17.3 g/dL.

Preterm neonates with a lower level of Hb during the early postnatal days are at higher risk for ROP development and need to be prioritized for screening.