Bilirubinemia May Protect Against Severe Retinopathy of Prematurity in Extremely Preterm Infants: Study

The study published in Pediatric Research has revealed intriguing findings regarding bilirubinemia and its potential protective effect against the severity of retinopathy of prematurity (ROP) in infants born at 29 weeks gestational age or earlier. The research provides new insights into how bilirubin levels might influence the development of ROP, a serious eye condition affecting premature infants.

Retinopathy of prematurity is a condition where abnormal blood vessels grow in the retina of premature infants, potentially leading to vision impairment or even blindness. It is influenced by several factors, including oxygen levels, gestational age, and overall health of the infant.

Bilirubin is recognized as an antioxidant, but observational studies on its role in influencing the incidence and severity of retinopathy of prematurity (ROP) in premature infants have yielded conflicting results. Considering this, Srujana Rallabandi, University of California, San Francisco, CA, USA, and Sanjiv B. Amin, Wayne State University, Detroit, MI, USA, hypothesized that the degree of bilirubinemia is inversely associated with oxidative stress-mediated retinopathy of prematurity.

For this purpose, the researchers conducted a prospective study to investigate whether bilirubinemia is linked to ROP in infants born at 29 weeks gestational age or earlier and with birth weights of 1000 grams or less. They measured total serum bilirubin (TSB) levels at least twice daily during the first week and at least daily during the second week to assess peak and average TSB levels. The study focused on evaluating the incidence and severity of ROP as the primary outcomes.

The researchers reported the following findings:

• Of the 193 infants studied, 110 developed ROP: 53 had mild (stage 1 in zone 2 or 3); 31 had moderate (stage 2 in zone 2 or 3); and 26 had severe ROP ( ≥ stage 3 in any zone or any stage in zone 1).
• Mean TSB levels were associated with the severity (adjusted odds ratio [AOR] 0.68) but not with the incidence of ROP (AOR 0.81).
• Peak TSB levels were also associated with the severity (AOR 0.71), but not with the incidence of ROP (AOR 0.71).

The findings from this prospective study suggest that bilirubinemia may have a protective effect against the severity of retinopathy of prematurity.

"The research presents a potential protective effect of bilirubinemia against severe ROP, challenging existing assumptions and suggesting a need for a more nuanced approach to managing bilirubin levels in preterm infants," the researchers concluded.

Reference:

Rallabandi, S., & Amin, S. B. (2024). Bilirubinemia and retinopathy of prematurity in infants ≤ 29 weeks gestational age. Pediatric Research, 1-7. https://doi.org/10.1038/s41390-024-03479-8