Banca de DEFESA: MARCIA MARILIA GOMES DANTAS

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE: MARCIA MARILIA GOMES DANTAS
DATA: 11/10/2013
HORA: 08:30
LOCAL: CONSEC - CCS
TÍTULO:

EFFECT OF ZINC SUPPLEMENTATION ON THE BIOELECTRICAL IMPEDANCE VECTOR IN PREPUBERTAL CHILDREN

PALAVRAS-CHAVES:

Zinc; Children; Electric impedance; Nutrition assessment

PÁGINAS: 28
GRANDE ÁREA: Ciências da Saúde
ÁREA: Medicina
RESUMO:

Optimal growth requires adequate nutrition, especially in childhood, where growth and development is intense. The prevalence of abnormal nutritional status has increased in children and adolescents in full development. Zinc is an essential nutrient, required for numerous metabolic functions, and its deficiency results in growth retardation, cell-mediated immune dysfunction and cognitive impairment. Although all micronutrient deficiencies are considered a risk factor to determine the growth delay in children, zinc deficiency stands out in this process. Moreover, the nutritional assessment is important to monitor the health and nutritional status of both healthy or ill children. There are many nutritional assessment methods. Although the body mass index (BMI) has an association with adiposity, it does not distinguish between weight changes due to fat mass, lean mass, or water. Therefore, the present study aimed to describe the nutritional status evaluated by the behavior of bioimpedance vector in healthy and eutrophic children after oral zinc supplementation compared to control group. This research was characterized as randomized controlled trial, triple-blind study, where 60 prepubertal children were divided in the control group (placebo) and experimental group (10 mg Zn/day), both supplemented during 3 mo. Body composition was assessed by Bioelectrical Impedance Vector Analysis (BIVA). The two components of the impedance vector Z, namely resistance, and reactance, standardized by height (H), are considered as two correlated normal random variables (i.e., a bivariate gaussian vector). These variables forming elliptical probability regions on the RXc plane, which are confidence ellipses for mean vectors and tolerance ellipses for individual vectors. The mean vectors from control and experimental groups were plotted each one as before and after oral zinc administration and then compared with the unpaired two-sample Hotteling’s T2 test. The 95% confidence ellipses of two mean vectors of each group were overlapping, which means that the position between the vectors at control and experimental groups was no statistically different (p > 0.05) in the RXc plane. The paired one-sample Hotelling’s T2 test determined a difference in mean vectors between the first measurement (before supplementation) and matching second measurement (after supplementation). The experimental group showed difference between before and after oral zinc supplementation, (p < 0.0001). By plotting the two components R/H and Xc/H measured in an individual subject as an individual impedance vector (a point) on the RXc graph, some children that were classified as eutrophic, according to BMI-for-age, fell outside the individual impedance vector, indicating moderate underhydration and obesity.  The oral zinc supplementation showed that tissue impedance has a tendency to normal. Longitudinal data are needed to investigate vector migration during the zinc supplementation. The reference values of the impedance vector can be used for clinical practice to assess children’s body composition.

MEMBROS DA BANCA:
Presidente - 1216686 - JOSE BRANDAO NETO
Externo ao Programa - 1149619 - SELMA SOUSA BRUNO
Externo à Instituição - MARIA JOSÉ DE CARVALHO COSTA - UFPB