Impaired energy expenditure and physical activity in children affected by GH deficiency measured by SenseWear Armband: preliminary results.

Abstract

Background: Influence of growth hormone on energy expenditure and physical performance is clearly known. Objective and hypotheses: The aim of our study is to evaluate the energy expenditure (EE) during physical (PA) and sedentary activities (SA), in a group of children/adolescents affected by growth hormone deficiency (GHD) compared to healthy subjects, using an objective measure as SenseWear Armband (SWA-BodyMedia). Patients, methods and results: These preliminary data included 13 untreated, consecutive GHD children and adolescents (6 males) (GH peak <10 ng/ml; IGF1 SDS -2.0±0.3) and 10 controls (6 males), age and sex matched. As expected, the GHD group showed statistically lower height (-2.7±0.9 vs 0.4±0.5 SDS), weight (-1.5±1.2 vs 1.1±0.6 SDS) and Body Mass Index (BMI) (-0.1±1.2 vs 0.6±0.2 SDS). The use of SWA demonstrated that the GHD children showed lower Energy expenditure, total (1007±458 vs 1337±125 cal/d;1.7±0.2 vs 1.9 ±0.2 Mets/d) and active (214±136 vs 435±88 cal/d;7±3 vs 13±4 cal/Kg/d) and spent statistically less time in physical activity (>3 Mets) (1.5 ±0.8 vs 2.3±1 h/d), especially moderate (3-6 Mets)(1.4±0.8 vs 2.2±0.9 h/d; 5.8±3.1 vs 9.2±3.9% of daily hours) compared with healthy subjects. A tendency to spend more time in sedentary activities was found in GHD group (16±4 vs 14±3 h/d), although not statistically significant. In multivariate regression IGF1 and BMISD resulted positive predictors of EE/daily (cal/daily) in GHD children. Conclusions: In conclusion our preliminary results seem to confirm that children affected by growth hormone deficiency showed lower energy expenditure as calories/daily and spent less time in physical activities compared to normal children. This result seems correlate to IGF1 values indicating a possible role of GH in physical performance. Further evaluations on greater number of patients, before and after GH therapy, are ongoing to confirm our findings.