Assessing body composition and energy expenditure in children with severe neurological impairment and intellectual disability

Abstract

Children with severe neurological impairment and intellectual disability are at increased risk of developing malnutrition. While in recent years increased use of gastrostomy feeding has turned this trend, children receiving tube feeding run the opposite risk of overnutrition. Maintaining a healthy diet for these children requires regular measurements of body composition and estimates of energy needs. However, a review of available literature did not provide enough evidence of valid instruments for measuring body composition. In addition, no equations exist to reliably estimate energy expenditure in these children. This thesis aimed to develop equations to measure body composition and estimate energy expenditure in these children. To accomplish this, in 61 children (32 male, age 10.1 ± 4.3) the outcomes of skinfold measurements and bioimpedance analysis (BIA) were compared to a reference method: the doubly labeled water method. While a newly-developed equation for skinfolds did not improve agreement, the new BIA equation did (R2 = 0.92, SEE=1.7 kg, RMSE=1.8 kg). In order to develop an equation to estimate energy expenditure, in 61 children data was recorded on degree of movement, mobility, muscle tone and presence of epilepsy. After analysis the variables degree of movement and mobility were selected by the statistical model. The resulting equation was based on 52 children, in whom all measurements were successfull (R2=0.69, SEE=207 kcal, RMSE=213 kcal). Although the standard error of this new equation is still considerable, it is a first step in the development of a group-specific equation. This thesis concludes with a preliminary guideline that aims to diagnose undernutrition and overnutrition in children with severe neurological impairment and intellectual disability.