Neonatal lipid exposure has long-term CV impact in premature infants
MedWire News: Short-term exposure to exogenous lipids in premature infants may have long-term impacts on the human cardiovascular system, study findings suggest.
The researchers found that individuals who were born prematurely and were exposed to intravenous lipids via breast milk as neonates, had increased aortic stiffness and reduced myocardial function in early adulthood, compared with those who were not exposed.
Furthermore, "the impact on aortic stiffness and myocardial strain in these individuals is graded depending on the maximum cholesterol level attained and amount of time elevated during this early period of cardiovascular development," the authors remark.
Paul Leeson (University of Oxford, UK) and colleagues performed a 25-year prospective follow-up study of a cohort enrolled into a randomized trial of milk feeding regimens. A total of 102 individuals born prematurely between 1982 and 1985 and weighing less than 1850 g at birth were included in the present study.
Of these, 18 had mothers who had received a brief, artificial, nutritional elevation in lipid levels postnatally in the form of an intravenous lipid infusion, and they were matched for age and gender to a group who had not been exposed to intravenous lipids (n=36). Aortic stiffness and left ventricular function were assessed in all participants by cardiovascular magnetic resonance imaging.
The researchers found that individuals who received intravenous lipids at birth had a 29% greater aortic stiffness in early adulthood, measured as mean pulse wave velocity (PWV), than those who had not (5.89 vs 4.57 m/s, respectively). The greatest change in aortic stiffness was observed in the abdominal aorta, notes the team.
These relationships were graded according to the elevation in neonatal cholesterol induced by intravenous lipids; the maximum level of cholesterol obtained in early postnatal life was significantly and positively associated with aortic PWV in young adulthood. This supports a "significant dose effect," remark Leeson et al.
In addition, these associations were independent of native cholesterol levels during the first decades of life, suggesting that "nutritional elevation of cholesterol in critical periods of early development may have a direct impact on the cardiovascular system."
Reporting in the journal Arteriosclerosis, Thrombosis, and Vascular Biology, the authors say that preterm birth accounts for 9.6% of all deliveries worldwide, making these findings of significant interest to public health.
However, "further work is required to understand the relevance of our findings to the narrower nutritional variation in cholesterol in normal neonatal life," they conclude.
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By Nikki Withers