Association between Early Postnatal Hydrocortisone and Retinopathy of Prematurity in Extremely Preterm Infants

Introduction: Retinopathy of prematurity (ROP) is a leading cause of preventable childhood blindness. We investigated the association of early postnatal low-dose intravenous hydrocortisone used for the prevention of bronchopulmonary dysplasia (BPD) with ROP outcome among extremely preterm infants in a Swedish cohort. Methods: This retrospective cohort study included extremely preterm infants born before 28 weeks of gestational age (GA). Infants born September 2020-August 2022, treated with low-dose intravenous hydrocortisone for prevention of BPD, were compared to untreated controls born September 2016-August 2020. Hydrocortisone was administered postnatally with a dose of 0.5 mg/kg twice daily for 7 days, followed by 0.5 mg/kg per day for 3 days. Logistic regression, adjusted for GA, birth weight (BW), sex, and parenteral nutrition, was used in the primary analysis. For robustness, we performed 1:1 propensity score (PS) matching followed by logistic regression. Results: Of 245 preterm infants included, 65 were treated with low-dose hydrocortisone and 180 were untreated controls. Incidence of ROP treatment was reduced in the hydrocortisone group 18.5% (12/65) versus controls 32.2% (58/180), p = 0.038. One-to-one PS matching (n = 62 + 62) confirmed the reduced incidence of ROP treatment in the hydrocortisone-treated infants (odds ratio [OR]: 0.38, 95% confidence interval [95% CI]: 0.16-0.88, p = 0.025). After adjusting for GA, BW, sex, and parenteral nutrition >= 14 days, the reduced risk of ROP treatment after early hydrocortisone treatment persisted (OR: 0.31, 95% CI: 0.16-0.60, p = 0.0005). Conclusion: Early postnatal low-dose intravenous hydrocortisone used to prevent BPD may reduce the risk of ROP treatment among extremely preterm infants.