Purpose: To investigate the characteristics of outlier infants for insights into ROP risk.
Methods: Chart data were collected from 1,354 infants screened for ROP at Weill Cornell Medical Center and Columbia University Medical Center. ROP exam results and clinical risk factors were recorded. The cohort was stratified by weight, highest ROP stage, and need for ROP treatment. Descriptive and correlational statistics were performed.
Results: For the overall cohort, regression analysis found that birth weight (OR: 0.741 per 100 g; 95 % CI: 0.606, 0.905), gestational age at birth (OR: 0.563 per week; 95 % CI: 0.454, 0.697), multiple gestation (OR 2.02, 95 % CI: 1.15, 3.56), bronchopulmonary dysplasia (OR: 4.68, 95 % CI: 1.93, 11.35), and necrotizing enterocolitis (OR 2.80, 95 % CI: 1.40, 5.16) were independent risk factors for treatment-requiring ROP. Black race was found to be a protective factor for treatment-requiring ROP (OR 0.244, 95 % CI: 0.095, 0.626). Among 15 infants with BW <500 g, there were no significant differences in any clinical risk factors between the 12 (80 %) with ROP vs the three (20 %) without ROP. Similarly, among infants with BW >1500 g, the 17 (9 %) with ROP only differed from the 166 (91 %) without ROP with respect to a higher incidence of necrotizing enterocolitis among those with ROP (11.8 % vs 0 %).
Conclusions: Although known clinical risk factors were predictive of ROP stage and need for laser treatment in this cohort, they were not significantly associated with ROP at extremes of birth weight. This suggests that other clinical, maternal, or genetic factors may protect from or predispose to ROP.