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Published on: April 2, 2021
The U.S. National Trend for Retinopathy of Prematurity
Hany Aly1, Hasan F Othman2, Chelsea Munster1
1Department of Neonatology, Cleveland Clinic Children's, Cleveland, Ohio.
Insights
Retinopathy of prematurity (ROP) and severe ROP increased in very low birth weight infants over 16 years. This trend correlated with longer hospital stays but not with changes in necrotizing enterocolitis (NEC).
Area of Science:
- Neonatalogy
- Pediatric Ophthalmology
- Clinical Research
Background:
- Supplemental oxygen is vital for premature infants but carries risks.
- Balancing oxygen use is critical to prevent mortality, necrotizing enterocolitis (NEC), and retinopathy of prematurity (ROP).
- Recent trends show more liberal oxygen use, necessitating an examination of associated outcomes.
Purpose of the Study:
- To analyze national trends in ROP for very low birth weight (VLBW) preterm infants.
- To assess concurrent trends in mortality, NEC, intraventricular hemorrhage (IVH), and length of hospital stay (LOS).
Main Methods:
- Analysis of deidentified data from the National Inpatient Sample (NIS) (2002-2017).
- Inclusion criteria: infants with gestational age ≤32 weeks and birth weight <1,500g.
- Statistical analysis using the Jonckheere-Terpstra test to identify trends.
Main Results:
- A significant increase in ROP and severe ROP prevalence was observed (p<0.001).
- Mortality significantly decreased (p<0.001), while NEC prevalence remained unchanged (p=0.222).
- Survived infants experienced a significant increase in median LOS (p<0.001).
Conclusions:
- A national trend of increasing ROP and severe ROP in VLBW infants occurred over 16 years.
- This rise in ROP was associated with increased LOS in survivors.
- Necrotizing enterocolitis rates did not change during the study period.
Objective:
The use of supplemental oxygen in premature infants is essential for survival. However, its use has been associated with unintended complications. The restricted use of oxygen is associated with increased mortality and necrotizing enterocolitis (NEC), whereas its liberal use is associated with increased risk for retinopathy of prematurity (ROP). Although there is no clear consensus on the acceptable oxygen saturation range, clinicians have recently become more liberal with the use of oxygen. We aim to assess (1) the national trends for ROP in very low birth weight preterm infants, and (2) the associated trends in mortality, NEC, intraventricular hemorrhage (IVH), and length of hospital stay (LOS).
Study Design:
We analyzed deidentified patient data from the National Inpatient Sample (NIS) of the Healthcare Cost and Utilization Project (HCUP) from 2002 to 2017. All infants with gestational age ≤32 weeks and birth weight <1,500 g were included. Trends in ROP, severe ROP, mortality, NEC, IVH, severe IVH, and LOS were analyzed using Jonckheere-Terpstra test.
Results:
A total of 818,945 neonates were included in the study. The overall mortality was 16.2% and the prevalence of ROP was 17.5%. There was a significant trend for increased ROP over the years (p < 0.001). Severe ROP was also significantly increased (p < 0.001). This was associated with a significant trend for increased median LOS in survived infants (p < 0.001). Mortality was significantly decreased (p < 0.001), whereas NEC and severe NEC did not change over time (p = 0.222 and p = 0.412, respectively).
Conclusion:
There is a national trend for increased ROP and severe ROP over the 16 years of the study period. This trend was associated with a significant increase in the LOS in survived infants without change in NEC.
Key Points:
· Prevalence of ROP and severe ROP has increased in VLBW infants over the 16-year study period.. · The prevalence of NEC did not change over the same time period.. · Increased ROP and severe ROP were consistent in all three GA and BW subgroups..

