Role of vitamin A on retinal function in infants at risk of retinopathy of prematurity

Abstract

Background: Preventive therapy for retinopathy of prematurity (ROP) is still lacking, and visual improvements after treatment are often poor. Vitamin A or plasma concentrations of retinol are low in preterm infants and reflect reduced hepatic stores. Early intramuscular (IM) vitamin A supplementation enhances survival and improves respiratory function at 36 weeks postmenstrual age (PMA) and may also protect against ROP.  This study was planned to test the hypothesis that dark adapted retinal sensitivity in preterm infants is improved by early high dose supplementation of vitamin A.

Method: A randomized double blind controlled trial of infants at risk of ROP (32 weeks gestation and or 1500 g birth weight) was performed on 76 infants, who had been admitted to neonatal units of Government Medical College, Jammu. Ocular abnormalities and predicted non-survival were excluded from the trial.

Results: 36 infants were randomly selected and kept as healthy controls, while, 40 were supplemented with the minimum 5 x IM Vitamin A injections till day 14. Plasma retinol was significantly higher in supplemented group as compared to the control group at 7^th day, while at 28^th day and at 36^th week PMA, this difference was not significant. Retinal sensitivity (log σ) at 36^th week was greater in the supplemented group, and some relation to Vitamin A intake per Kg weight of the infant over the first 4 weeks of life was found.

Conclusion: Vitamin in as IM dose to preterm infants at the risk of ROP improves retinal sensitivity at 36 week’ PMA.