Mechanistic studies in swine to evaluate newborn infant vitamin A dosing strategies (260.1)

Abstract

Clinically, infant care is challenging especially in resource‐poor developing countries where small‐for‐gestational‐age is common and in any country when an infant is born prematurely. Several components comprise perinatal mortality of infants. Children suffering from vitamin A deficiency have a greater risk of irreversible blindness and dying from infectious diseases. Supplementation programs are an approach to address this issue. Studies have found little or no improvement in infant vitamin A status after supplementing with 25,000 IU vitamin A. Based on WHO’s recommendations, children ages 6 ‐ 11 mo receive 100,000 IU vitamin A and those 12 ‐ 59 mo receive 200,000 IU vitamin A every 4 to 6 mo. Multi‐centered and randomized trials of infant supplementation programs have shown inconsistent results. Infant supplementation itself has been debated due to the higher incidence of bulging fontanelle in vitamin A‐dosed infants. Therefore, a series of studies were performed in a swine model to evaluate infant dosing regimens. Newborn piglets from vitamin A‐depleted sows received a placebo, 25,000, 50,000, or 200,000 IU vitamin A supplements at birth. Tissues were collected and analyzed. The degree of vitamin A deficiency did not seem to affect the response to treatment. High doses may be quickly catabolized to maintain balance. Lung and spleen require chylomicron vitamin A to maintain concentrations, which was confirmed with a tracer study using α‐retinol. The tracer study also showed quick uptake in the adrenal gland. Low birth weight piglets took up less vitamin A. Food sources of vitamin A performed better than supplementation at improving vitamin A status of offspring.Grant Funding Source: Supported by the Nutrition Unit at the World Health Organization.