67 - Hospitalization Rates for Phototherapy in Neonates with TcB Values >5.5 mg/dL Below the Phototherapy Threshold

Publication Number: 1060.67

Saman Aryal, NYCHHC/ Woodhull Medical and Mental Health Center - - Brooklyn, NY, Queens, NY, United States; Sheng Hsin Chen, NYCHHC / Woodhull Medical Center, Brooklyn, NY, United States; Olufunto O.. Shonibare, New York Health and Hospitals/ Woodhull, Brooklyn, NY, United States; Laxmi Aryal, Woodhull hospital, Newyork, NY, United States; Prince O.. Ansong, Woodhull Hospital, Newark, NJ, United States; Shuja Ahmed Shaik, NYC Health and Hospitals/ Woodhull, New York, NY, United States; Alexander Rodriguez, Woodhull Hospital, Brooklyn, NY, United States; Marsha Medows, New York University Grossman School of Medicine, New York, NY, United States

Background: Neonatal jaundice, or hyperbilirubinemia, affects more than half of all term infants. Although most cases are benign, some may progress to severe hyperbilirubinemia, leading to acute bilirubin encephalopathy or kernicterus. Early recognition and management are crucial to prevent these outcomes. Total serum bilirubin (TSB) measurement remains the diagnostic gold standard but is invasive. Transcutaneous bilirubin (TcB) testing provides a non-invasive, reliable, and rapid alternative for screening and discharge decisions. The 2022 AAP guidelines define phototherapy thresholds but do not specify how far below these thresholds bilirubin levels must be for safe discharge. Understanding outcomes for infants discharged near, but below, these thresholds can help optimize follow-up and resource use.

Objective: To determine hospitalization rates for phototherapy among neonates discharged with TcB values >5.5 mg/dL versus ≤5.5 mg/dL below the AAP phototherapy threshold and to identify associated demographic and clinical factors, including ethnicity and feeding type.

Design/Methods: A retrospective cohort study of 1,848 term and near-term infants discharged from a single birth center (September 2022-September 2024) was conducted. The difference between TcB and the AAP phototherapy threshold (threshold-TcB) was calculated. Infants were categorized as >5.5 mg/dL or ≤5.5 mg/dL below the threshold. The primary outcome was rehospitalization for phototherapy within one week post-discharge. Analyses used Chi-square and t-tests for categorical and continuous variables, with p< 0.05 considered significant.

Results: Of 1,848 infants, 46 (2.5%) were rehospitalized for phototherapy. Readmission occurred in 7.9% of those discharged ≤5.5 mg/dL below threshold versus 1.2% of those >5.5 mg/dL below (χ²=53.0, p< 0.001), a nearly sevenfold higher risk for the closer group. Asian and Hispanic infants had higher bilirubin levels and readmission rates (p < 0.05). Exclusive breastfeeding showed a trend toward higher rehospitalization rates (3.3%) than formula (1.4%) or mixed feeding (1.6%) (p=0.061).

Conclusion(s): Strict adherence to uniform follow-up guidelines may result in unnecessary visits and hospitalizations for infants whose TcB levels are safely below the treatment threshold. This can increase stress for families, create additional workload for clinicians and residents, and lead to inefficient use of healthcare resources. Individualizing follow-up based on bilirubin safety margins, particularly when TcB is >5.5 mg/dL below the phototherapy threshold, may safely reduce unnecessary interventions while maintaining quality newborn care.

Figure 1. Rate of Rehospitalization by Discharge Bilirubin Margin Below the Phototherapy Threshold
Infants discharged ≤5.5 mg/dL below the phototherapy threshold had significantly higher rehospitalization rates for phototherapy (7.9% vs. 1.2%; χ²=53.0, p=0.001).

Table 2. Clinical and Demographic Factors Associated With Rehospitalization for Phototherapy
Asian and Hispanic ethnicity was associated with higher bilirubin levels and readmission rates (p < 0.05). Breastfeeding showed a trend toward higher readmission (p=0.061). Bilirubin margin from threshold was strongly predictive of readmission (p < 0.001), with no differences by gestational age or weight.

Table 3. Follow-Up Outcomes by Discharge Bilirubin Difference from the Phototherapy Threshold
Infants discharged ≤5.5 mg/dL below the phototherapy threshold had higher rates of rehospitalization and fewer no-intervention visits (p < 0.001), while repeat bilirubin testing (TcB or TSB) occurred at similar rates between groups (p=0.42).