Background and aims Aetiology of BPD is multifactorial with prenatal and postnatal factors being involved. First, we aimed to evaluate the association between chorioamnionitis and BPD. Secondly, the effect of other perinatal factors on the risk of developing BPD were analysed.
Methods Retrospective analysis of all infants with GA <32 weeks or BW <1500 g. admitted into our hospital between 2002–2010. 120 patients who died before 36 weeks of PMA were excluded.
Results The average GA was: 29,7 ± 3 s; 217/432 (50%) had any type of chorioamnionitis (histological or clínical); 75/432 (17.4%) met diagnostic criteria for BPD at 36 weeks.
Univariate analysis: lower GA, any type of chorioamnionitis, DAP and duration of mechanical ventilation (MV) were associated with an increased risk of DBP (p < 0.05).
Multivariate analysis: administration of antenatal steroids or chorioamnionitis did not independently modify the risk of BPD. But adding both, the effect became statistically significant protective for BPD (OR 0.52, 95% CI 0.03 to 0.79).
Days in MV is the only factor that independently increased the risk of BPD. Neither a lower GA nor the presence of PDA had significantance; but, the risk of BPD was higher in the presence of PDA and MV together: every day in MV increased the risk of BPD (OR 1.130, 95% CI1.001- 1.27).
Conclusions Chorioamnionitis in coexistence with antenatal corticosteroids decreases the risk of BPD. Mechanical ventilation is the main risk factor for BPD. In the presenceof DAP, ventilation increases the risk of BPD.