Pulmonary vasodilator therapy in preterm children with bronchopulmonary
dysplasia; a nationwide study
Objectives: This study aimed to map prescription patterns of
pulmonary vasodilator therapy in children with bronchopulmonary
dysplasia (BPD). Working hypothesis: Pulmonary vasodilator drug
therapy is used in children born preterm suffering from BPD-associated
pulmonary hypertension, but patient selection, extent of diagnostics
with catheterization and co-morbidities are largely unknown. Study
design: A descriptive national registry-based study. Patient
selection and methodology: All children below seven years of age who
had been prescribed a pulmonary vasodilator during a ten-year period,
2007-2017, born preterm (gestational age, GA <37 weeks) and
classified as BPD, were included. Information on prescriptions was
retrieved from the Swedish Prescribed Drug Register and information on
patient characteristics and comorbidities was retrieved by linkage to
national registers held by the National Board of Health and Welfare.
Results: In total, 74 children were included, 54 (73%) born at
GA 22-27 and 20 (27%) at GA 28-36. Single therapy was most common, N=64
(86.5%), and sildenafil was most frequently prescribed, N=69 (93%).
Bosentan, iloprost, macitentan and/or treprostinil were mainly used for
combination therapies, N=10 (13.5%). Patent ductus arteriosus (PDA) or
atrial septal defect (ASD) was present in N=29 (39%) and N=25 (34%)
children respectively, and N=20 (69%) versus N=3 (12%) underwent
closure. Cardiac catheterization was performed in N=19 (26%) patients.
Median duration of therapy was 4.4 (0.5-14.1, 95% percentiles) months.
Total mortality was N=7 (9%). Conclusions: Preterm children with
BPD are prescribed pulmonary vasodilators, often without prior
catheterization and sildenafil was most common. Diagnostic tools,
effects, and drug safety needs further evaluation.