Results.
Baseline characteristics of preterm newborns by gestational age are presented in Table 1. As expected, statistically significant differences by gestational age were found in variables such as birth weight, duration of supplemental oxygen, oxygen use at discharge, use of surfactant therapy and antenatal corticosteroids, frequency of BPD, hyaline membrane disease and patent ductus arteriosus.
116 met the criteria for bronchopulmonary dysplasia ( incidence of 25.7% 95% CI, 21.6-29.9). Bronchopulmonary dysplasia was mild in 11%, moderate in 62% and severe in 27% of patients. Among patients with different levels of BPD severity, there were statistically significant differences in birth weight, duration of supplemental oxygen, oxygen use at discharge, frequency of sepsis and pulmonary hypertension, see table 2. After modeling regression analysis, the final variables associated with BPD severity levels were: sepsis (OR 2.37 CI 95% 1.04-5.40) and pulmonary hypertension (OR 3.79 CI95% 1.19-12), see table 3.