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No clinical correlation between bilirubin levels and severity of retinopathy of prematurity
Shigeharu Hosono1, Tsutomu Ohno, Hirofum Kimoto
1Division of Neonatology, Saitama Children's Medical Center, Japan.
Insights
This study found no evidence that bilirubin protects against severe retinopathy of prematurity (ROP) in premature infants. Bilirubin levels did not differ significantly between infants with varying ROP severity.
Area of Science:
- Neonatal Medicine
- Ophthalmology
- Biochemistry
Background:
- Retinopathy of prematurity (ROP) is a significant cause of visual impairment in premature infants.
- Bilirubin, a byproduct of heme breakdown, has shown antioxidant properties in vitro.
- The potential neuroprotective role of bilirubin has been investigated in various neonatal conditions.
Purpose of the Study:
- To investigate the hypothesis that elevated bilirubin levels confer a protective effect against the development of severe retinopathy of prematurity (ROP).
- To analyze the correlation between daily bilirubin concentrations and ROP severity in extremely preterm infants.
Main Methods:
- A cohort of 76 infants born at 24-25 weeks' gestation were monitored.
- Indirect ophthalmoscopy was used to assess ROP degree and progression.
- Daily serum bilirubin levels were analyzed and correlated with ROP severity (less than prethreshold, prethreshold, and threshold ROP).
Main Results:
- No statistically significant differences in clinical characteristics or treatments were observed among the ROP severity groups.
- Daily mean bilirubin concentrations during the first 14 days of life did not significantly differ between infants with varying ROP severity.
- The duration of phototherapy was the only variable showing statistical difference among groups.
Conclusions:
- The study found no distinct protective effect of bilirubin against the development of severe retinopathy of prematurity.
- These findings do not support the hypothesis that bilirubin mitigates ROP severity in extremely preterm infants.
Purpose:
To evaluate the hypothesis that bilirubin has a protective effect against the development of severe retinopathy of prematurity (ROP).
Methods:
An assessment of 76 infants born at 24 and 25 weeks' gestation and admitted to the level III neonatal intensive care unit at Saitama Children's Medical Center was made. Indirect ophthalmoscopy fundus examinations were performed on all infants to identify the degree and progression to threshold ROP. We analyzed the daily bilirubin levels and grouped the patients according to the severity of ROP based on the infant's worst ROP examination. The first group was comprised of infants with less than stage 3 ROP and infants with stage 3 ROP. The second group was infants with less than prethreshold ROP or prethreshold ROP, and infants with threshold ROP. Next, we divided the infants into 3 groups: less than prethreshold ROP, prethreshold ROP, and threshold ROP. The daily changes in serum bilirubin concentrations during the first 14 days of life were determined for each infant. Three groups (less than prethreshold ROP, prethreshold ROP, and threshold ROP) were comparable as to their basic data, clinical characteristics, and treatments.
Results:
ROP was found in 76 infants. There were no statistical differences in the clinical characteristics and treatments, excluding the duration of phototherapy, among the 3 groups. During the first 14 days of age, there were no significant differences in the daily mean bilirubin concentrations according to the groups separated by severity of ROP.
Conclusion:
These results indicate that there is no distinct protective effect of bilirubin on the development of severe ROP.
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