The association between respiratory distress and nonpulmonary morbidity at 34 to 36 weeksʹ gestation

Objective The study was undertaken to determine whether respiratory distress syndrome (RDS) is associated with an increased risk of nonpulmonary morbidity in neonates born between 34 to 36 weeksʹ gestation. Study design We performed a matched case-control study of 75 infants with (cases) and 75 without (controls) RDS, delivered between 34 and 36 weeksʹ gestation. Infants with RDS and no other causes for respiratory failure (anomalies, hydrops, asphyxia) were included. Controls were matched for gestational age at birth, year of care, gender, plurality, and race. Inpatient records were reviewed for the incidence of nonpulmonary morbidities before discharge. McNemar test and conditional logistic regression were used to evaluate differences between cases and controls. Results Our study cohort was 69% male, 48% white, 33% African American, and 19% Hispanic. Cases had longer hospital (11 vs 7days) and neonatal intensive care unit stays (10 vs 7days), and more frequent apnea-bradycardia (30% vs 5%), pneumonia (12% vs 1%), and suspected sepsis diagnoses (27% vs 3%), P ≤ .008 for each. Antibiotic use (96% vs 45%), transfusion (20% vs 0%), phototherapy (57% vs 29%), and hyperalimentation (57% vs 4%) were more common in the RDS group, P ≤ .002 for each. Other major morbidities (intraventricular hemorrhage, patent ductus arteriosus, necrotizing enterocolitis, bronchopulmonary dysplasia) were uncommon in cases and controls. Similar results were obtained when controlling for mode of delivery and antenatal steroid use. Conclusion RDS at 34 to 36 weeks is associated with increased morbidity and neonatal interventions. In the absence of RDS, major morbidity is uncommon.