B O D Y P R O P O R T I O N S I N S M A L L F O R G E S T A T I O N A L A G E C H I L D R E N A F T E R R E C E I V I N G G R O W T H H O R M O N E T R E A T M E N T distribution25. Ibanez et al showed that in SGA children a dramatic transition to-‐ wards central adiposity and insulin resistance occurs between the age of two and four years26. Thereby, overweight former SGA children have an increased risk for the components of the metabolic syndrome compared with overweight former AGA children27. Thus, an increase in weight in SGA children has to be prevented at an early age. For that reason, monitoring of weight is of great importance and especially the question “Is there an increase in fat or in fat-‐free mass?” must be answered accord-‐ ing to the body composition. The change in body composition can be measured by the Deuterium method. However, this method seems to be less accurate in SGA children based on the observation that in GHD children a change is visible of 0.93 compared to SGA of 0.62. This difference must be based on an increase in FFM more than a shift from FM to FFM because SGA children already have a body fat percent-‐ age, which is reduced before treatment17,18. Therefore, as a result of rhGH treat-‐ ment, a decrease in FM can hardly be expected and mainly an increase in FFM can be measured. That means that the detected increase in weight must be based on an increase in FFM instead of FM. Therefore not only the relation between the change in TBW and the increase in height after one year is explored in this study, but also the relation between the change in BMI and the change in weight for height. BMI and weight for height of SGA children barely changed during the first year of rhGH treatment, while the change in TBW was already evident after six weeks of treatment. The fact that the BMI did not change in contrast to weight for height can be explained by the increase in height. In daily practice TBW measurement is not applicable, because this measurement is not easily achievable. Weight for height measurement seems to be a better measur-‐ ing method to evaluate the change in body composition than BMI. BMI turns out to be higher than in children (below the age of 10 years) with a smaller height, alt-‐ hough the child has a weight that suits its height, taking the P3, P50 and P97 values into account, as is illustrated in (Table 2). For that reason we must remark that the use of BMI must be carefully interpreted in children below the age of 10 years. 67
Proefschrift binnenwerk Manon Ernst_DEF.indd
To see the actual publication please follow the link above