Role of Zinc in Catch-up Growth of Low-Birth Weight Neonates

Abstract

Low birth weight (LBW) is a challenging public health problem. Its high priority stems from the fact that it is a major predictor of infant mortality and that it contributes substantially to the overall burden of childhood handicap. Growth and nutritional deficits are almost universal in LBW babies. Many other sequel of LBW may be attributed to these growth and nutritional deficits, making them a main target for early and effective interference. Micronutrient deficiency, including zinc, contributes greatly to impaired growth, health, and development of children in less-developed countries. Results of studies regarding the role of zinc supplementation in improving growth in LBW neonates are conflicting. In some studies, zinc supplementation enhanced more weight gain and reduced the incidence of low birth weight related problems. Other studies showed no added benefit of zinc supplementation to enhance growth or significantly reduce morbidity in LBW infants. As zinc status is difficult to identify due to its tight homeostatic mechanisms, zinc supplementation trials have become the best source of information about zinc nurture around the world and especially in risk groups such as children. The aim of this randomized placebo-controlled trial was to clarify the role of this essential nutrient on growth promotion, enhancing growth and fasting catch-up in this vulnerable group of children, as well as to find out a proposed relationship between zinc effect on growth and the main growth hormone mediator, IGF-1. This study is a double-blind randomized placebo-controlled trial for assessing the impact of oral zinc therapy on the catch-up growth of low-birth-weight neonates delivered at Ain Shams University Maternity Hospital. A secondary objective was to measure the levels of serum IGF-1 in both groups and to relate those levels to zinc supplementation and catch up growth in both groups. The study was conducted in Ain Shams University Maternity Hospital NICU during the period from October 2010 to May, 2012. The population of this study comprised 200 LBW neonates of both sexes selected from those admitted to NICU with a birth weight ranging between 1500 and less than 2500 g. Neonates delivered at less than 28 weeks’ gestation, those with clinical or laboratory evidence of considerable illness, congenital malformations or chromosomal aberration syndromes were excluded from the trial. Eligible neonates were randomly allocated into one of