Weekly Zinc Chelate Supplementation on Children's Growth

Phase 2

Completed

Conditions: Short Stature

Interventions: Dietary Supplement: Zinc amino acid chelate
Other: Placebo

Registration Number: NCT01911260

Lead Sponsor: Federal University of São Paulo

Brief Summary: The purpose of this study is to measure the effect of weekly zinc supplementation on schoolchildren with growth deficit or normal stature.

Detailed Description: Zinc is an important micronutrient for humans. Trials with zinc have shown positive effects of supplementation on growth, but there is still a lack of results on schoolchildren population. This Randomized Double-Blind Controlled Trial was design to measure the effect of weekly zinc supplementation on schoolchildren with growth deficit and normal stature. Schoolchildren were allocated into two homogeneous groups named Growth Deficit (HAZ \< -1,5 Z-score), and Normal Stature (HAZ between -1,0 and ±1,0 Z-score) and were randomly assigned to compose two exposed and two control groups to receive a supplement of 30mg of zinc amino acid chelate or placebo individually once a week, during 12 weeks. Children's heights were measured at the end of supplementation period and again after 12 weeks.

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 199

Inclusion Criteria

Children with one and a half or more standard deviations below the mean height for age and gender of the reference population (Z-score under -1.6) were included in the Growth Deficit group (GD). For the Normal Stature group(NS), HAZ was set up as being between -1 and +1 standard deviations from the mean height reference for age and sex.

Exclusion Criteria

Children of GD group were evaluated by a Pediatrician specialized in growth disorders with the objective of excluding any organic or genetic condition correlated with growth deficit.

Study & Design

Study Type: INTERVENTIONAL

Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Growth Deficit+zinc amino acid chelate	Zinc amino acid chelate	Children with one and a half or more standard deviations below the mean height for age and gender of the reference population (Z-score under -1.6) were included in the Growth Deficit group (GD). During twelve weeks, children received weekly 1ml of lemon flavor caramel syrup containing zinc amino acid chelate at 3%, i.e. the equivalent to 30mg of elemental zinc per ml, disposed into an individual amber glass, containing 20ml of syrup. The supplement administration was made individually with 1ml BD Plastipak disposable syringe, directly into the child's mouth, by the principal investigator. The chosen supplementation day was Tuesday. Therefore, the following weekdays were reserved to supplement any absent student.
Growth Deficit receiving placebo	Placebo	Children with one and a half or more standard deviations below the mean height for age and gender of the reference population (Z-score under -1.6) were included in the Growth Deficit group (GD). During twelve weeks, children received weekly 1ml of lemon flavor caramel syrup, disposed into an individual amber glass, containing 20ml of syrup. The supplement administration was made individually with 1ml BD Plastipak disposable syringe, directly into the child's mouth, by the principal investigator. The chosen supplementation day was Tuesday. Therefore, the following weekdays were reserved to supplement any absent student.
Normal Height receiving placebo	Placebo	For the Normal Stature group (NS), HAZ was set up as being between -1 and +1 standard deviations from the mean height reference for age and sex. During twelve weeks, children received weekly 1ml of lemon flavor caramel syrup, disposed into an individual amber glass, containing 20ml of syrup. The supplement administration was made individually with 1ml BD Plastipak disposable syringe, directly into the child's mouth, by the principal investigator. The chosen supplementation day was Tuesday. Therefore, the following weekdays were reserved to supplement any absent student.
Normal Height+zinc amino acid chelate	Zinc amino acid chelate	For the Normal Stature group (NS), HAZ was set up as being between -1 and +1 standard deviations from the mean height reference for age and sex. During twelve weeks, children received weekly 1ml of lemon flavor caramel syrup containing zinc amino acid chelate at 3%, i.e. the equivalent to 30mg of elemental zinc per ml, disposed into an individual amber glass, containing 20ml of syrup. The supplement administration was made individually with 1ml BD Plastipak disposable syringe, directly into the child's mouth, by the principal investigator. The chosen supplementation day was Tuesday. Therefore, the following weekdays were reserved to supplement any absent student.

Primary Outcome Measures

Name	Time	Method
Change in Height-for-Age Z-score (HAZ) From End of Supplementation to End of Follow-up Period.	Height-for-Age Z-score was measured at the End of Supplementation period and again at the End of Follow-up period, with a 12 weeks interval.	Schoolchildren were allocated into two homogeneous groups named Growth Deficit (HAZ \< -1,5 Z-score), and Normal Height (HAZ between -1,0 and ±1,0 Z-score), and were randomly assigned to compose two exposed groups to receive a supplement of 30mg of zinc amino acid chelate, and two control groups to receive placebo individually once a week, during 12 weeks. Children's heights were measured at the End of Supplementation period and again after 12 weeks (Follow-up period). In combination with sex and age we transformed stature to Height-for-Age, expressed in Z-score, which was calculated as a number of standard deviations or Z-scores below or above the reference mean or median value, according to the formula below: Z-score = (observed value - median value of the reference population) / standard deviation value of reference population. We analyzed and discussed the change in HAZ (HAZ at the End of Follow-up period - HAZ at End of Supplementation).

Secondary Outcome Measures