Bronchopulmonary dysplasia: incidence and risk factors.

Introduction: Bronchopulmonary dysplasia is the most common chronic pulmonary sequela among very low birth weight infants. The objective of this study was to estimate its incidence in our Neonatal Unit over the past 5 years and analyze associated risk factors.

Population And Methods: An observational and analytical study was conducted in a retrospective cohort, using data obtained from a prospective database of infants born at Hospital Italiano de Buenos Aires with a birth weight of less than 1500 grams between January 2010 and December 2014. The incidence of bronchopulmonary dysplasia and its association with several secondary outcome measures were studied.

Results: Two hundred and forty-five patients were included. The incidence of moderate/severe bronchopulmonary dysplasia was 22%, and it was associated with a younger gestational age and lower birth weight. A significant association was observed with surfactant use, mechanical ventilation requirement, and length of mechanical ventilation. Patients with moderate/severe bronchopulmonary dysplasia had a higher incidence of patent ductus arteriosus and late-onset sepsis. A lower birth weight (adjusted odds ratio |-#91;aOR|-#93;: 0.99, 95% confidence interval |-#91;CI|-#93;: 0.991-0.997, p< 0.001) and the length of mechanical ventilation (aOR: 1.08, 95% CI: 1.01-1.15, p < 0.01) remained associated following adjustment for other outcome measures. In addition, an association was observed among patients with intrauterine growth restriction born at less than 32 weeks of gestational age (OR: 4.71, 95% CI: 1.68-13.2).

Conclusions: The incidence ofbronchopulmonary dysplasia in our unit was associated with a lower birth weight and the length of mechanical ventilation. Among infants born at less than 32 weeks of gestation, intrauterine growth restriction accounted for an additional risk.