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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 Summary and Conclusion 182 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 catchup 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 the following two groups: Group I: LBW neonates, AGA or SGA on oral zinc therapy at a dose of 20 mg/kg; and Group II: LBW neonates AGA or SGA on placebo at an equal volume to that of zinc solution calculated for weight. Anthropometric measurements were taken including birth weight and length, head, waist, chest, and mid‐upper arm circumferences, triceps and sub‐scapular skin fold thicknesses. Measurements were taken on the right side. In addition blood samples were taken from all included infants initially for measurement of serum zinc level, and at 6‐monthold for measurement of serum IGF‐1 level. Summary and Conclusion 183 Bottles for oral intake, of the same shape and size were used to contain either zinc sulfate or placebo. The oral solution contained 2 grams of zinc sulfate in 100 ml volume with a concentration of 2 % (20 mg/ml), or the same basic composition (distilled water) without zinc sulfate (placebo solution). The bottles were numbered serially by the independent investigator and the codes were kept confidential until the study was finished. The dose of therapy was a volume assumed to supply 20mg/kg/day zinc sulfate when zinc solution was given. Therapy lasted 6 months of daily oral intake. Of the recruited 200 neonates, 121 (60.5%) were males, while 79 (39.5%) were females. The mean gestational age at delivery was 35.08 ± 1.93 weeks (range: 32 – 40 weeks). Forty eight (24%) neonates were delivered at term, while 152 (76%) were delivered preterm. The mean birth weight was 1966.29 ± 307.61 g (range: 1500 – 2490 g). Of the included 200 neonates, 129 (64.5%) were appropriate for gestational age (AGA), while 71 (35.5%) were small for gestational age (SGA).All of the included 200 neonates were below the 10th percentile for birth weight; 186 (93%) were below the 10th percentile for length at birth; while 185 (92.5%) were below the 10th percentile for HC at birth.The median initial serum zinc concentration in included neonates was 111.35 g/dl (range: 31 – 554 g/dl; interquartile range [IQR]: 83.3 – 145.5 g/dl).The recruited neonates were randomized into one of two groups:Group I [Zinc Group] (n=108): including neonates who received oral zinc syrup treatment for 6 months; and Group II [Placebo Group] (n=92): including neonates who received placebo for the same duration.The overall drop‐out Summaryrate was 29/200 (14.5%). There was no significant difference between neonates of both groups regarding initial zinc concentration. The mean weight at 12‐month‐old follow‐up visit was significantly higher among infants of group I [Zinc Group] when compared to those of group II [Placebo Group]. The length, HC, waist circumference, chest circumference, MAC and triceps SFT were all significantly higher in infants of group I [Zinc Group] when compared to those of group II [Placebo Group], and subscapular SFT was still nonsignificantly different. The proportions of infants, who had values ≥ the 10th percentile for weight, length and HC at the 12‐month‐old follow‐up visit, were significantly higher in group I [Zinc Group] when compared to group II [Placebo Group]. Oral zinc therapy was associated with a 24.88%, 25.98% and 19.6% higher proportion of values ≥ the 10th percentile regarding weight, length and HC at 12‐month‐old visit, respectively [NNT = 4, 4 and 5, respectively].The mean values for weight, length and HC at the 12‐month‐old followup visit were significantly higher in group I [Zinc Group] compared to group II [Placebo Group] in infants who were AGA. The mean values for weight and HC were, however, comparable in both groups in infants who were SGA.The mean values for weight, length and HC at the 12‐month‐old followup visit were significantly higher in group I [Zinc Group] when compared to group II [Placebo Group] in infants who were preterm. The mean value for weight was, however, comparable in both groups in infants who were term.The mean values for weight, length and HC at the 12‐month‐old follow‐up visit were significantly higher in group I [Zinc Group] when compared to group II [Placebo Group] in male Summary and Conclusion |