Growth Hormone Secretion in Prader‐Willi Syndrome

Abstract

Integrated 12-hour growth hormone secretion studies, peak growth hormone response to clonidine provocation. Somatomedin-C levels, T-4 and TSH levels were studied in six growth-retarded children with the Prader-Willi syndrome, of whom five had a 15 q-karyotype. Only one of the subjects was obese. All showed abnormally low growth hormone secretion. None achieved a nocturnal peak above 10 micrograms/l, none had a mean nocturnal level over 1.8, and none showed a level above 8 micrograms/l after clonidine provocation. These findings contrasted with normal TSH in all and normal T-4 in five. These findings suggest that the poor linear growth in the Prader-Willi syndrome is caused by a true deficiency of growth hormone secretion, and that the low growth hormone levels observed in such cases are not an artifact of obesity.

Ghrelin in Growth and Development

“…Obesity is thought to result mainly from hyperphagia, decreased perception of satiety and obsessive and compulsive behaviors that are primarily food related [84, 85]. Patients also present with short stature, possibly due to GH deficiency of hypothalamic origin [86, 87]. …”

Body composition in Prader-Willi syndrome compared with nonsyndromal obesity: Relationship to physical activity and growth hormone function

“…However, a structural lesion has not yet been discovered. [4][5][6][7] Moreover, the pattern of adiposity in patients with PWS and the reduced lean mass, including reduced bone mass, especially in the limbs, 8 have a close resemblance to the body composition present in children with growth hormone deficiency. Although GHD cannot be confirmed in all patients, the effect of growth hormone intervention does support a functional GHD.…”

Clinical management of behavioral characteristics of Prader–Willi syndrome

“…[104][105][106][107] In contrast to children with simple obesity, there is no enhancement of growth velocity despite onset of obesity in individuals with PWS. During adolescence, the growth rate declines due in part to inefficient testosterone and estrogen levels, resulting in the absence of the pubertal growth spurt.…”