Abstract
Introduction: Recent evidence suggests that preterm birth is a possible risk factor for high blood pressure (BP) in later life. The most widely quoted blood pressure centiles for very low birth weight (VLBW, ≤1500 g birth weight) infants at corrected term gestation is based on a cohort with mostly late preterm or term infants (Zubrow curves). Objectives: The objective of this study was to determine the clinical utility of the Zubrow curves in diagnosis of hypertension in VLBW infants at their term corrected gestational age (CGA). Patients and Methods: In a case-control study, we compared BP in 75 VLBW infants at 40 weeks CGA (cases) to 69 full term infants admitted to neonatal intensive care unit (NICU) (controls). Results: In spite of having lower weights, VLBW infants compared to term infants (2612.8 ± 546 vs. 3308.2 ± 373 g, P ≤ 0.001) had higher average systolic (88.8 ± 7.6 vs. 82.33 ± 8.5 mm Hg; P ≤ 0.001) and mean BP (61.2 ± 6.6 vs. 57.61 ± 6.9, P = 0.01). Although 41% (31/75) VLBW infants would have met the criteria for hypertension according to Zubrow curves only 4% (3/75) were diagnosed with hypertension. Conclusion: Since Zubrow BP centiles were based on a heterogeneous population of infants including preterm and term infants, new BP centiles based on chronological data from VLBW infants would allow a better definition of hypertension in these infants and identify the threshold BP for initiating treatment.
Highlights
Recent evidence suggests that preterm birth is a possible risk factor for high blood pressure (BP) in later life
Implication for health policy/practice/research/medical education: The exact incidence of hypertension in very low birth weight (VLBW) infants at corrected term gestation is difficult to estimate due to lack of a robust and universally accepted definition for hypertension
There is a need for a large multicenter study to develop more appropriate gestational age or birth weight based BP centiles with chronological data from birth through term corrected gestation age, infancy and beyond
Summary
Recent evidence suggests that preterm birth is a possible risk factor for high blood pressure (BP) in later life. Objectives: The objective of this study was to determine the clinical utility of the Zubrow curves in diagnosis of hypertension in VLBW infants at their term corrected gestational age (CGA). The odds of hypertension diagnosis were even higher for those born extremely preterm (2.51 [CI: 1.11-5.68]) [2] In another large cohort of 18 year-olds, the risk of elevated systolic blood pressure (SBP) was twofold higher in premature infants born between 24-28 weeks gestational age [5]. VLBW infants, compared to term infants, are more frequently exposed to multiple risk factors (maternal hypertension, umbilical arterial lines, steroids, acute kidney injury) during their prolonged neonatal intensive care unit (NICU) stay and are at risk for developing chronic lung disease (CLD-need of oxygen at 36 week corrected gestational age [CGA]), which can potentially elevate their BP [7]. Since the reported incidence of hypertension ranges from 0.2% to 3% [7], we speculate that neonatologists are often comfortable to diagnose hypertension in these VLBW infants at higher BP thresholds than that are suggested by Zubrow curves
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
