Project Description:
A. PURPOSE OF THE STUDY
To provide a method of measurement or algorithm that can be used in a clinical environment that will accurately assess body fat and the estimation of energy expenditure in youth with spina bifida (SB).
B. SPECIFIC AIMS
This multisite, cross-sectional study will include 232 youth with SB, ages 5 -18 (stratified by age and mobility status). Participants will have three different body composition measures and four alternative height measures performed. Each measure of height will be used in a Body Mass Index (BMI) calculation and body composition measures. Doubly Labeled Water (DLW) analysis and calculations will provide the criterion body fat%, fat-free mass and Total Daily Energy Expenditure (TDEE). Study sites include four pediatric SB programs in different geographical regions. The study will be conducted at each sites Clinical and Translational Science Institute research unit or designated research setting.
Aim 1. Develop an algorithm that accurately models body fat% and categorizes weight status in youth with SB using clinically feasible, cost-effective and efficient measures of body composition (four-site skinfolds, waist circumference and bioelectrical impedance analysis) and/or surrogate height (arm span, recumbent, knee height and ulnar length) measures.
a) Examine whether mobility status, sex, Body Mass Index (BMI) with surrogate height, or pubertal status are important determinants in the model, and determine if corrections are needed for these variables.
Aim 2. Using Doubly Labeled Water (DLW), measure Total Daily Energy Expenditure (TDEE) and develop a prediction equation for energy requirements of the sample.
a)Examine average TDEE based on age, sex and mobility status (walks or primarily uses a wheelchair).
b) Develop a prediction equation based on actual TDEE to predict energy requirements with a best-fit model based on fat-free mass, sex, age, mobility status, assistive device use, and height and/or weight.
Exploratory Aim: Using a nutrition screener, physical activity screener, and accelerometers describe the dietary intake and the physical activity frequency and duration in youth with SB. This exploratory aim will provide a preliminary understanding of obesity-related behaviors, which is currently lacking for this population.
