Purpose: To delineate racial differences in the incidence and time course of ROP in a large cohort of premature infants.
Methods: The secondary analysis of data from the two Postnatal Growth and ROP Studies (G-ROP-1 and G-ROP-2) that were collected in 41 hospitals in North America from 2006 to 2017. According to self-reported maternal race, premature infants were classified into 3 groups: White (N = 5580), Black (N = 3252), and Asian (N = 353). Incidence, severity, and time course of ROP; plus disease; and postnatal weight gain rate were compared among racial groups.
Results: Black infants had significantly smaller BW (mean 1035 vs. 1131 vs.1144 grams, P < .001) and lower GA (28.2 vs. 28.6, vs. 29.1 weeks, P < .001) than White and Asian infants. However, Black infants had lower incidences of severe ROP (11.1% vs. 12.4% vs. 11.9%), ROP (42.1% vs. 43.2% vs. 30.6%), and plus disease (3.6% vs. 6.3%, vs. 5.9%) than White and Asian infants (BW and GA adjusted risk ratio for Black vs. White 0.69 for severe ROP, 0.83 for ROP, 0.44 for plus disease, all P < .0001). Mean daily-weight-gain on days of life 11-20 and 21-30 were similar across groups (P > .05), but lower in Black and Asian infants on days 31-40 (P < .001). There were no differences in the timing of severe ROP and ROP across racial groups.
Conclusions: Despite relatively lower GA, BW, and daily-weight-gain, Black preterm infants had lower incidences of ROP and plus disease than White preterm infants. The mechanisms for these differences require further investigation.
Keywords: Retinopathy of prematurity; infants; premature infants; race; racial difference; retina; weight gain.