Pulmonary hypertension is a common outcome of bronchopulmonary dysplasia (BPD) in premature infants, with one in every or five pre-term babies with BPD going on to develop PH, a study reports.
The study, “Bronchopulmonary dysplasia and pulmonary hypertension: a meta-analysis,” showed that the odds ratio (the likelihood) of developing PH is three times greater in premature newborns with BPD than those without it. The analysis, based on a review of 16 published studies, appeared in the Journal of Perinatology.
BPD is a chronic lung disease that affects infants with low birth weights and those in respiratory distress, and it results from damage to the lungs caused by mechanical ventilation (respirator) and long-term oxygen use.
Information for the study was obtained from four databases and included cohort, case control, and randomized studies. Those papers with a high risk of bias were excluded.
Finding revealed a 17% pooled incidence of PH in babies with BPD of any severity, which rose to 24% in those with moderate-to-severe BPD. Not surprisingly, the severity of BPD (mild, moderate or severe) determined the likelihood of PH development, with a pooled PH incidence of 4% in mild BPD babies and 33% in severe cases.
The study also examined short-term outcomes in BPD patients with and without PH. While the times for initial hospitalization or supplemental oxygen use, and the need for home oxygen, showed no difference between these two groups, those premies with both conditions had a much higher likelihood of dying while in the hospital than those with BPD only (odds ratio, 5.29 vs. 1).
While the work is a comprehensive review of available information, the team acknowledged its data might be affected by discrepancies among the studies, such as the varying definitions of PH used, how cases were selected, when PH screening were conducted in the infants, and the duration of follow-up.
Another challenge is that PH symptoms do not overtly differ from those of BPD, so an initial PH diagnosis may have been delayed and its impact masked.
Little data was available to judge long-term outcomes, the authors said, suggesting more research is needed to “better delineate long-term pulmonary and neurodevelopmental outcomes in preterm infants with BPD-associated PH.”
Still, the analysis suggests that an initial PH screening of patients with moderate and severe cases of BPD may be justified. But, as the researchers noted, “[f]urther data on outcomes in the context of routine screening and treatment are required before widespread implementation of screening can be recommended.”