Blood pressure trajectories in extreme preterm infants with and without bronchopulmonary dysplasia: a longitudinal cohort study.

objectiveTo compare longitudinal blood pressure (BP) patterns in extremely preterm (EP) infants with and without bronchopulmonary dysplasia (BPD) and examine associations with clinical characteristics.

methodsThis retrospective cohort study analysed weekly non-invasive systolic, diastolic, and mean BP measurements from 28 weeks postmenstrual age (PMA) to term infants cared for at the Women’s Wellness and Research Center, Doha. BP trajectories were compared longitudinally, with additional analysis by BPD severity.

resultsAmong 201 infants, 95 (47%) developed BPD. These infants were born at lower gestational age and birth weight and had greater exposure to respiratory therapies, higher rates of patent ductus arteriosus, longer hospitalisation, and more frequent cardiovascular support. BP trajectories differed between groups. At 28–29 weeks PMA, systolic, diastolic, and mean BPs were slightly lower in infants with BPD. From approximately 32–36 weeks PMA, BP values converged, and later PMAs showed higher systolic and mean pressures in the BPD group. The proportion of systolic BP values above the 95th percentile was generally higher among infants with BPD, although differences were not consistently significant. In multivariable regression, BPD was not independently associated with hypertensive BP episodes. Male sex was associated with lower odds of hypertensive systolic, diastolic, and mean BP episodes, while higher birth weight was associated with fewer systolic hypertensive episodes.

conclusionEP infants with BPD demonstrate distinct BP trajectories, characterised by early relative hypotension followed by higher systolic pressures later in hospitalisation. However, BPD was not independently associated with hypertensive BP episodes. Sex and physiologic maturity appear to be stronger determinants of BP variability, supporting the importance of longitudinal BP monitoring in EP infants.