Importance: Previous studies suggest that race or ethnicity may be associated with risk for developing retinopathy of prematurity (ROP). Little is known about how socioeconomic factors mediate the relationship between race or ethnicity and ROP outcomes.
Objective: To evaluate how socioeconomic factors, in the context of race and ethnicity, are associated with ROP outcomes.
Design, setting, and participants: This retrospective cohort study used US Census Bureau income data and electronic medical records from neonatal intensive care units at 4 hospitals, UCLA Mattel Children's Hospital, UCLA Santa Monica Hospital, Cedars-Sinai Medical Center, and Harbor-UCLA Medical Center. Eligible participants included neonates born at a gestational age (GA) of 30 weeks or less, birth weight less than 1500 g, or a GA at birth greater than 30 weeks but with an unstable clinical course. Participants were screened for ROP between January 1, 2010, and December 31, 2020.
Exposures: Race and ethnicity data, GA, demographic and clinical information, proxy household income, and health insurance status were collected as risk factors.
Main outcomes and measures: Diagnosis and severity of ROP were the main study outcomes. Severity was determined according to a classification system developed by the Early Treatment for Retinopathy of Prematurity Cooperative Group.
Results: In a crude model, Hispanic neonates were more likely to be diagnosed with ROP (OR, 1.70; 95% CI, 1.20-2.42) and had more severe ROP (OR, 2.24; 95% CI, 1.21-4.15) compared with non-Hispanic White neonates; these associations were no longer found when adjusting for GA and socioeconomic factors (OR, 1.12; 95% CI, 0.68-1.82, and OR, 1.67; 95% CI, 0.80-3.52, for ROP diagnosis and severity, respectively). In a fully adjusted model, lower GA was the primary predictor of ROP incidence (OR, 0.52; 95% CI, 0.48-0.57; P < .001), and higher median household income was associated with higher GA (OR, 0.26; 95% CI, 0.09-0.43; P = .002).
Conclusions and relevance: In this cohort study, GA was the primary driver of disparities in ROP outcomes in a heterogeneous population of neonates in Los Angeles, California. When examined in the context of socioeconomic factors, GA did not differ between racial and ethnic groups. Studies of disparities associated with race and ethnicity should consider these constructs in conjunction with other sociodemographic factors and social determinants of health.