Ghrelin levels in young children with Prader-Willi syndrome

To explore the hypothesis that high ghrelin levels contribute to obesity in Prader-Willi syndrome (PWS), we assessed whether the increased levels observed in older persons with PWS exist in very young children, before the onset of hyperphagia. We measured ghrelin levels in nine children with PWS (17-60 months of age) and eight healthy control subjects of equivalent body mass index (BMI), age, and sex. PWS and control groups had equivalent BMI (16.8 ± 1.4 vs 16.1 ± 0.9 kg/m 2, respectively; P = .24), age (37.8 ± 15.4 vs 50.3 ± 17.7 months; P = .14), and sex. PWS and control groups also had equivalent fasting levels of total ghrelin (787 ± 242 vs 716 ± 135 pg/mL, respectively; P = .24), bioactive ghrelin (102 ± 35 vs 91 ± 23 pg/mL; P = .45), insulin, and glucose. Ghrelin correlated negatively with BMI among controls (r = −0.760, P = .029) but not PWS (r = 0.015, P = .97). Children