Purpose
To analyze various risk factors for the incidence and severity of retinopathy of prematurity (ROP) with particular attention to race.
Methods
Data was analyzed from 914 infants who received screening for ROP in the neonatal intensive care unit at Loma Linda University Children’s Hospital from 2001 to 2010. Excluded from this study were 250 patients due to incomplete follow-up (202) or death prior to reaching a disease endpoint (48). The data consisted of demographic characteristics, presence of major comorbidities, duration of oxygen supplementation, and incidence and severity of ROP. A multiple logistics regression model was used to determine the relation of these variables to the incidence (disease at any stage) and severity (stage 3-5 or high risk disease requiring intervention) of ROP.
Results
The incidence of ROP during the studied time period was 42.3% (387/914) for disease at any stage and 22.1% (202/914) for severe disease. Among infants who were diagnosed with ROP, 51.2% (198/387) experienced spontaneous resolution of their disease while 48.8% (189/387) required laser photocoagulation. There was no significant variation in ROP incidence due to sex (p = 0.91) or race (p = 0.18) when adjusting for other factors. White infants collectively had similar rates of disease compared to black infants (42.6% versus 41.8%, respectively). When considered separately, white Hispanic infants had higher rates of ROP (46.2%) compared to their non-Hispanic white counterparts (38.3%), although this disparity was insignificant. Disease severity and laser therapy rates were also similar across the racial groups. Birth weight, gestational age, and oxygen exposure were strongly linked to the development of ROP (p < 0.0001), but demonstrated non-linear relationships with regards to disease severity. A comparison of disease-free infants to ROP infants demonstrated a median birth weight of 1300 grams versus 815 grams, a median gestational age of 30 weeks versus 26 weeks, and a median supplemental oxygen duration of 20 days versus 94 days, respectively. ROP was associated with the presence of bronchopulmonary dysplasia (OR 7.99, 95% CI 5.86 - 10.88), patent ductus arteriosus (OR 3.48, 95% CI 2.62 - 4.61), necrotizing enterocolitis (OR 3.13, 95% CI 2.23 - 4.39), and sepsis (OR 2.29, 95% CI 1.75 - 3.00).
Conclusions
Contrary to the findings of the CRYO-ROP study, race is not an independent risk factor for the incidence or severity of ROP.
Keywords: 706 retinopathy of prematurity •
464 clinical (human) or epidemiologic studies: risk factor assessment •
463 clinical (human) or epidemiologic studies: prevalence/incidence