Cerebral injury and retinopathy as risk factors for blindness in extremely preterm infants

Abstract

Objective This study investigates whether and to what extent cerebral injury is associated with bilateral blindness in extremely preterm infants, which has been attributed mainly to retinopathy of prematurity (ROP). Design Multicentre analysis of children born from 1994 to 2021 at gestational age 22 0/7 to 28 6/7 weeks with follow-up at 18-26 months. Logistic regression examined the adjusted association of bilateral blindness with severe ROP and/or cerebral injury among extremely preterm infants. Exposures Severe ROP and cerebral injury, the latter defined as any of the following on cranial imaging: ventriculomegaly; blood/increased echogenicity in the parenchyma; cystic periventricular leukomalacia. Main outcome measures Bilateral blindness, defined as a follow-up examination meeting criteria of 'blind-some functional vision' or 'blind-no useful vision' in both eyes. Results The 19 863 children included had a mean gestational age of 25.6 +/- 1.7 weeks, mean birth weight of 782 +/- 158 g and 213 (1%) had bilateral blindness. Multiplicative interaction between ROP and cerebral injury was statistically significant. For infants with only severe ROP (n=3130), odds of blindness were 8.14 times higher (95% CI 4.52 to 14.65), and for those with only cerebral injury (n=2836), odds were 8.38 times higher (95% CI 5.28 to 13.28), compared with the reference group without either condition. Risks were not synergistic for infants with both severe ROP and cerebral injury (n=1438, adjusted OR=28.7, 95% CI 16.0 to 51.7, p<0.0001). Conclusions In a group of extremely preterm infants, severe ROP and cerebral injury were equally important risk factors for blindness. Besides ROP, clinicians should consider cerebral injury as a cause of blindness in children born extremely preterm. Trial registration number NCT00063063.