Prethreshold retinopathy in premature infants with intrauterine growth restriction

Abstract

Aim: To determine, among very preterm newborns, whether those who are growth-restricted are at increased risk of retinopathy of prematurity (ROP), and to explore whether the mixed findings of prior studies are the consequence of sampling based upon birthweight instead of gestational age.

Methods: Using data from the ELGAN Study, we created logistic regression models of prethreshold ROP risk to adjust for confounders and calculate odds ratios and 99% confidence intervals. We created scatter plots to display the gestational age/birthweight relationship in infants enrolled in studies with different selection criteria.

Results: Low gestational age [23-24 weeks, OR 11.6 (2.9, 47); 25-26 weeks, 8.1 (2.1, 32)] and severe growth restriction [birthweight Z-score <-2, OR 9.1 (1.1, 76)] were associated with increased risk of prethreshold ROP. We documented in scatter plots that a sample defined by birthweight has an excess of gestationally older, severely growth-restricted newborns.

Conclusion: In this sample, low gestational age and severe growth restriction were associated with increased risk of prethreshold ROP.

Keywords: Extremely low gestational age newborn; Growth restriction; Prematurity; Retinopathy; Retinopathy of prematurity.