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Preterm birth attenuates association between low birth weight and endothelial dysfunction.

Mikael Norman·Helena Martin
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Abstract

BACKGROUND: Low birth weight predisposes to later coronary disease. To further elucidate the mechanisms behind this association and their timing, vascular endothelial function-a key factor in early pathophysiology of atherosclerosis-was studied in 54 infants born either before the third trimester or at term. METHODS AND RESULTS: All subjects were studied at 3 months of postnatal age. A laser-Doppler technique was used to measure skin perfusion before and after transdermal iontophoresis of acetylcholine (ACh; an endothelium-dependent vasodilator). In infants born at term (n=19; birth weight range: 2230 to 4205 g), maximum perfusion after ACh was 109+/-8 perfusion units (PU, mean+/-SEM) in normal-birth weight controls compared with 56+/-13 PU among those who had been small for gestational age at birth (P<0.01). In infants born preterm (n=35; birth weight range, 722 to 1868 g), ACh induced similar perfusion responses among subjects appropriate for gestational age (113+/-16 PU) and in those small for gestational age at birth (109+/-19 PU). CONCLUSIONS: Impairment in human endothelial function associated with low birth weight occurs or emerges late in pregnancy. Very preterm birth attenuates this association. Different gene-environment interactions in the third trimester may contribute to this finding.

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AcetylcholineBirth WeightBlood PressureEndothelium, VascularFemaleGestational AgeHumansInfantInfant, Low Birth WeightInfant, NewbornInfant, PrematureInfant, Small for Gestational AgeInfant, Very Low Birth WeightLaser-Doppler FlowmetryMalePregnancyPregnancy Trimester, ThirdReference ValuesRegional Blood FlowSex FactorsSkinVasodilationVasodilator AgentsClinical TrialControlled Clinical TrialJournal ArticleResearch Support, Non-U.S. Gov't

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Mikael Norman, Helena Martin. 2003-08-18. Preterm birth attenuates association between low birth weight and endothelial dysfunction.. https://doi.org/10.1161/01.cir.0000085069.09770.3d

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