Background: Zinc is an essential micronutrient for humans and zinc deficiency makes the human body unable to continue with proper growth and development, get sick more times and prolong the time of illness. Chronic kidney disease (CKD) is a chronic condition with serious long-term consequences and requires nutritional support and periodic nutritional evaluation to prevent the development of protein-energy malnutrition. There are few studies on zinc deficiency in children with CKD. Therefore, the purpose of this study was to evaluate the effect of two doses of zinc supplementation (ZS) on the nutritional status of children with CKD.
Methods: A randomized multicenter trial was conducted in 48 CKD patients (23 women) under 18 years of age, for one year. This study was designed in two phases. At random, the participants took 30 or 15 mg/day of zinc sulfate, respectively. Monthly anthropometric measurements were made. Biochemical analysis was performed before and after supplementation. Hypozincemia was determined by serum zinc concentration (SZC) using atomic absorption spectrophotometry. The positive or negative change in the Z-score of the body mass index (BMI), in the levels of serum albumin, zinc and C-reactive protein (CRP) of the patients, was used to evaluate the effect of ZS.
Results: Mean SZC and serum albumin were normal before and after ZS. Men had a higher mean SZC than women. Despite the ZS, there were no significant changes in serum albumin, zinc, and CRP levels. However, there was a positive and significant association between SZC and serum albumin before (p = 0.000) and after (p = 0.007) ZS. In both ZS groups, there was a small but positive and significant change in body mass and normalization in BMI Z-index, hypoalbuminemia, hypozincemia, and high CRP, especially with ZS 30 mg/day. More than 40% of the children had hypozincemia before and after ZS.
Conclusion: Zinc supplementation may be beneficial for the nutritional status of children and adolescents with CKD, especially with 30 mg of zinc daily.