Distribution of Bioelectrical Impedance Vector Values in Multi-ethnic Infants and Pre-school Children

Background & Aims: Ethnicity may influence bioimpedance values. The goal of this study was to measure total body impedance vector in infants and pre-school children in Brazil and compare them with those reported in other countries.

Methods: We analyzed bioelectrical impedance from a sample of 255 healthy Brazilian children, aged 1-36 months, using the RXc graph method (tetrapolar analysis at 50 kHz frequency). The 95%, 75% and 50% tolerance ellipses were plotted by age group.

Results: The mean impedance vector showed migration across age groups, with progressive higher reactances and lower resistances as age increased. The mean bioimpedance vectors from the present sample of Brazilian children were different from those of European children of the same age ranges.

Conclusions: Our results confirm the importance of defining reference values of total body impedance vector for each country in view of the considerable ethnic diversity among different geographical areas.