Red cell distribution width and its association with retinopathy of prematurity

Objective: The aim of this study was to evaluate whether there is a relationship between red cell distribution width (RDW) values and the development of retinopathy of prematurity (ROP) in premature infants.

Methods: This retrospective study was conducted on a total of 159 infants with gestational age (GA) < 35 weeks including 77 infants diagnosed as ROP (patients' group) and 82 infants without ROP (control group) between September 2015 and January 2018. RDW values of the preterm infants were obtained from their medical records (routine postpartum cord blood sample and follow-up venous blood samples taken at first week, second week and first month). The possible relationship between RDW values and clinical features of ROP development was evaluated.

Results: The mean GA of all infants was 29.2 ± 2.4 (24-35) weeks, and the mean birth weight was 1268 ± 419 (550-2500) g. The RDW values measured in the first and the second weeks were significantly higher in infants with ROP compared with those wihout ROP (p < .001 for both). There was no statistically significant difference between the groups in terms of cord blood and first month RDW values (p = .719, p = .108, respectively). The first and second week's RDW values of infants with ROP requiring treatment (severe ROP) were significantly higher than those of infants with ROP not requiring treatment (mild ROP) (p = .005, p = .031, respectively), but no statistically significant difference was observed between the groups in terms of cord blood and first month values (p = .114 and p = .371, respectively).

Conclusion: RDW is an easily accessible and inexpensive marker that may reflect the clinical risk factors for ROP. Follow-up measures of RDW have the potential to help clinicians for the prediction of ROP development in the first 2 weeks postnatally.