Background: To examine the role of variations in vascular endothelial growth factor (VEGF) and pigment epithelial-derived factor (PEDF) levels and VEGF/PEDF ratio in predicting the occurrence of retinopathy of prematurity (ROP) in extremely premature human babies.
Methods: This is a retrospective hospital based case-control study of 54 preterm neonates born at or before 32 weeks of gestation between 2006 and 2007 at the Neonatal Intensive Care Unit of the First People’s Hospital Affiliated to Fudan University. Birthweight was less than 1250 g. Eleven diagnosed with ROP were identified as cases. A control group of 43 infants, closely matched for birthweight and gestational age, was selected. The levels of VEGF and PEDF were measured at different time points of postnatal ages. Two-way repeated measure analysis of variance (ANOVA) was performed to examine the time trend.
Results: Vascular endothelial growth factor level in ROP cases showed an increasing trend during the postnatal 35 day age (p < 0.01), while it was persistently decreasing in the control group (p = 0.025). In contrast, PEDF level in the control group was steadily increasing with postnatal day ages, while it remained approximately at the same level in the study group. On the other hand, the PEDF/VEGF ratio in cases was found to be extremely high at the beginning, then continuously declined during the entire study period, while it remained steady in the control group during the same period.
Conclusion: Increased expression of VEGF levels was found to be associated with older postnatal day age in our study. Monitoring of variations in VEGF level and PEDF/VEGF ratio might be helpful in predicting the occurrence of ROP in premature human babies.