Original Article
Incidence of Retinopathy of Prematurity and Risk Factors Among Premature Infants at a Neonatal Intensive Care Unit in Canada
Abstract
Purpose:
To study the incidence of retinopathy of prematurity (ROP) in a neonatal intensive care unit and obtain information on risk factors associated with ROP.
Methods:
Four hundred twenty-three infants were screened for ROP between July 2006 and July 2010. Demographic information, clinical data, and risk factors were reviewed.
Results:
The incidence was 40.4% (171 infants) for ROP, 9.2% (39 infants) for severe ROP, and 5.67% (24 infants) for laser treatment. Mean gestational age and birth weight were significantly lower among infants with ROP versus those without ROP (26 ± 0.13 vs 28.55 ± 0.12 weeks, P < .0001 and 840.5 ±17.49 vs 1,190.24 ± 20.20 g, P < .0001, respectively). Birth weight (P < .001), gestational age (P < .001), mechanical ventilation therapy (P = .039), and necrotizing enterocolitis (P = .019) were independent risk factors for ROP.
Conclusion:
Gestational age and birth weight were the most significant risk factors for developing ROP. The study population had an elevated percentage of infants with birth weight less than 1,000 g (extremely low birth weight), yet there was no corresponding increase in severe ROP incidence and treatment when compared to other studies.
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