Thirteen-Year Trends in Retinopathy of Prematurity Among High-Risk Preterm Infants Treated in a Neonatal Intensive Care Unit in South Korea

Purpose: This study aimed to examine trends in the incidence, risk factors, and clinical features of retinopathy of prematurity (ROP) among high-risk preterm infants in a South Korean neonatal intensive care unit over 13 years. Methods: A retrospective study included 1114 high-risk preterm infants with gestational age (GA) < 32 weeks or birthweight (BW) < 1500 g, admitted to Seoul National University Children's Hospital from January 2009 to December 2021. Follow-up eye examinations were conducted at 3 years postnatal age. Trends in ROP incidence, risk factors, and ophthalmic complications were analyzed. Results: The overall ROP incidence was 37.1% (413/1114), and 17.9% (199/1114) required treatment. Over the study period, GA and BW significantly increased (p<0.05), but no trends were observed for ROP incidence or laser treatment rates. Lower GA, lower BW, and moderate to severe bronchopulmonary dysplasia (BPD) were significant risk factors for treated ROP (p<0.001). Infants treated with laser therapy showed a higher incidence of myopia, astigmatism, anisometropia, strabismus, and cataract at 3 years compared to those with mild or no ROP. Conclusions: Although mean GA and BW increased over the 13-year period, the incidence of ROP and the proportion requiring treatment did not show a statistically significant temporal decline and exhibited substantial year-to-year variation. Lower GA, lower BW, and moderate to severe BPD were key risk factors for severe ROP. Laser-treated infants experienced more ophthalmic complications, emphasizing the need for long-term ophthalmic monitoring of high-risk preterm infants.