Differences in risk factors for retinopathy of prematurity development in paired Twins: A Chinese population study

K. Yau et al. Purpose. To determine the differences in risk factors for retinopathy of prematurity (ROP) in paired twins.Methods. A retrospective medical record review was performed for all paired twins screened for ROP between 2007 and 2012. Screening was offered to very low birth weight (≤1500 grams) and preterm (≤32 weeks) neonates. Twins 1 and 2 were categorized based on the order of delivery. Maternal and neonatal covariates were analyzed using univariate and multivariate regression analyses for both ROP and Type 1 ROP.Results. In 34 pairs of Chinese twins, the mean gestational age (GA) was 30.2 ± 2.0 weeks. In Twin 1, smaller GA (OR = 0.44, P=0.02), higher mean oxygen concentration (OR = 1.34, P=0.03), presence of thrombocytopenia (OR = 1429.60, P<0.0001), and intraventricular hemorrhage (OR = 18.67, P=0.03) were significant risk factors for ROP. For Twin 2, a smaller GA (OR = 0.45, P=0.03) was the only risk factor. There were no significant risk factors for ROP in Twin 1 or Twin 2 on multivariate analysis.Conclusion. In Chinese twin pairs, smaller GA was the only common risk factor for ROP while Twin 1 was more susceptible to the postnatal risks for ROP.