Red blood cell transfusion frequency and the risk and severity of bronchopulmonary dysplasia in preterm infants: a retrospective cohort study.

BACKGROUND

Red blood cell (RBC) transfusion is a common intervention for anemia in preterm infants; however, its association with bronchopulmonary dysplasia (BPD) remains debated. While biological mechanisms suggest potential harm, the clinical impact of transfusion frequency on BPD incidence and severity remains unclear.

OBJECTIVE

To investigate whether RBC transfusion frequency is independently associated with the risk and severity of BPD in preterm infants born before 32 weeks of gestation.

METHODS

This retrospective cohort study included preterm infants (< 32 weeks gestational age) admitted to the NICU at Zhangzhou Affiliated Hospital of Fujian Medical University between January 2020 and December 2022. Only transfusions administered before 36 weeks postmenstrual age were included. Clinical data, including transfusion frequency, hemoglobin levels, and respiratory diagnoses, were collected. Logistic regression was used to identify independent risk factors for BPD, and ROC curve analysis determined the optimal transfusion threshold. Subgroup and sensitivity analyses were conducted to evaluate confounding effects.

RESULTS

Among 228 included infants, 184 (80.7%) received at least one RBC transfusion. The BPD group received a higher number of transfusions (mean 4.24 vs. 1.89, p < 0.001). Multivariate analysis identified transfusion frequency (OR = 1.245; 95% CI: 1.023-1.514; p = 0.049) and lower gestational age (OR = 0.749; 95% CI: 0.561-0.998; p = 0.05) as independent risk factors for BPD. ROC analysis demonstrated transfusion frequency effectively predicted BPD (AUC = 0.749), with ≥ 4 transfusions (sensitivity 51%, specificity 77%) correlating with increased severity (Kendall's τ_b = 0.453, p < 0.001). Neonatal hemoglobin levels inversely correlated with transfusion requirements (r=-0.187, p < 0.001). Subgroup analysis confirmed this association across GA strata (p < 0.05). Early transfusion (≤ 14 days of life) was not associated with increased severity.

CONCLUSION

RBC transfusion frequency is an independent, dose-dependent risk factor for BPD in preterm infants. Reducing unnecessary transfusions and optimizing anemia management may help mitigate BPD risk and severity.