371 - Prophylactic Arginine Supplementation and Its Role in Preventing BPD in Extremely Preterm Infants

Publication Number: 1355.371

Stefani M. Doucette, University of Calgary, Calgary, AB, Canada; Muhammad Zaid H. Hussain, University of Texas Medical Branch School of Medicine, Houston, TX, United States; Sunil K. Jain, University of Texas Medical Branch, Galveston, TX, United States; Harish Amin, University of Calgary, Calgary, AB, Canada; Selphee Tang, Alberta Health Services, Calgary, AB, Canada; Abhay Lodha, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada

Background: The prophylactic use of L-arginine in preventing necrotizing enterocolitis (NEC) in preterm infants is well-documented in various studies, supporting its efficacy. However, its role in the prevention of bronchopulmonary dysplasia (BPD) remains poorly understood.

Objective: To evaluate the association between routine arginine supplementation and the incidence of bronchopulmonary dysplasia (BPD) and mortality in infants born at less than 29 weeks gestational age (GA).

Design/Methods: This retrospective cohort study included infants born at < 29 weeks gestation and admitted to Foothills Medical Centre, Calgary, between August 1999-May 2007. The pre-supplementation cohort (August 1999-March 2003; Group I) was compared to the post-supplementation cohort (October 2003-May 2007; Group II)(6 months washout period), following the introduction of routine arginine supplementation in April 2003. Primary outcomes included BPD (defined as oxygen dependency at 36 weeks postmenstrual age) and death before 36 weeks GA. Logistic regression was used to adjust for confounders.

Results: Among 676 eligible infants (Group I: 306 [pre-supplementation], Group II: 370 [post-supplementation]) (Figure 1), Group I and Group II had mean birthweights (range) of 839 g(410-1380) and 903 g (440-1560) (p < 0.001) and mean GAs (range) were 26 (22-28) and 26 (23-28)(p=0.022) respectively (Table 1). The incidence of BPD decreased from 85% to 73% (adjusted OR 0.52, 95% CI 0.31-0.87). The composite outcome of BPD or death before 36 weeks GA decreased from 88% to 76% (adjusted OR 0.50, 95% CI 0.30-0.82). Mortality before 36 weeks GA decreased significantly (20% vs. 10%, p< 0.001), though adjusted analysis did not show a statistically significant difference (adjusted OR 0.53, 95% CI 0.24-1.17) (Table 2).

Conclusion(s): Routine arginine supplementation in extremely preterm infants was associated with a significant reduction in BPD and the composite outcome of BPD or mortality. These findings support further investigation into the role of arginine in neonatal pulmonary health and its potential as a preventive strategy for high-risk populations.

Figure 1: Patient Study Flowchart


Table 1: Maternal and Neonatal Characteristics
*Chi-squared test for categorical variables; T-test or Wilcoxon rank sum test for continuous variables
aDexamethasone
bConventional, HFOV, jet, or oscillator


Table 2: Neonatal Outcomes Before and After Routine Arginine Supplementation
OR: odds ratio; CI: confidence interval; BPD: bronchopulmonary dysplasia of those who survived to 36wks GA; GA: gestational age
BPD defined as those infants who survived to 36 weeks + 0 days and required any respiratory support at that time including mechanical ventilation, CPAP, nasal cannula oxygen.
*Chi-square test.
1Adjusted for: gestational age, sex, cesarean delivery, antenatal corticosteroids, APGAR scores <7 at 5 minutes, small for gestational age (SGA), necrotizing enterocolitis (NEC), severe neurological injury (IVH grade 3 ± periventricular leukomalacia), postnatal steroids, caffeine