Bone Mineral Density of Prepubertal Age Girls with Turner’s Syndrome While on Growth Hormone Therapy

Abstract

Bone mineral densities and growth velocities of young girls with Turner’s syndrome treated with recombinant human growth hormone at an age before the decreased levels of estrogens secondary to their ovarian failure could contribute to osteopenia were studied. Twelve patients with a mean chronological age of 8.9 ± 0.9 years and a mean bone age of 6.9 ± 0.8 years received growth hormone therapy for over 2 years (0.5 IU/kg/week s.c). Mean growth velocities increased significantly from a baseline level of 3.5 ± 0.4 cm/year to 6.4 ± 0.3 and 5.7 ± 0.4 cm/year at 12 and 24 months of therapy, while height SDS improved from -3.1 ± 0.4 at baseline to -2.7 ± 0.3 and -2.4 ± 0.3 at 12 and 24 months, respectively. Total bone calcium as well as cortical bone mineral density of our patients while on recombinant human growth hormone were similar to that of a control group of prepubertal healthy children paired for bone age and height; bone density of trabecular bone was however increased in our patients when compared to healthy controls (0.791 ± 0.04 vs. 0.669 ± 0.02 g/cm²; p < 0.025). We conclude from our study that the bone mineral status of young girls with Turner’s syndrome on growth hormone therapy seems to be normal.

Long-term hormone replacement therapy preserves bone mineral density in Turner syndrome

“…Adolescent girls with TS with spontaneous puberty have BMD in the normal range, while in TS girls who underwent induced puberty, BMD was in the osteopenic range in all and in the osteoporotic range in 30% (8), and young TS does not attain peak BMD despite proper HRT started in adolescence (35). This suggests that estrogen plays a role in obtaining and maintaining maximal BMD.…”

Epidemiological, endocrine and metabolic features in Turner syndrome

“…In these studies patients with spontaneous menstruations had normal BMD, while patients without menstruations had reduced BMD (44,45). Further, GH seems to improve BMD (46,47), although in these two small studies no untreated control group of girls with Turner syndrome was included, and the patients were followed for up to 2 years only. In a recent 7-year study with GH treatment given at 3 different doses, where bone mineral density was studied by phalangeal radiographic absorptiometry, volumetric bone density was found to be normal or increased in a dose-dependent manner (48).…”

Epidemiological, endocrine and metabolic features in Turner syndrome

“…GH treatment seems to increase bone mineral density (BMD) in girls (139,140), although in these two small studies no untreated control group of girls was included, and the patients were followed for up to 2 years only. However, during short-term (2 months -1 year) GH treatment a decrease in BMD takes place, although it increases collagen turnover (as an indirect marker of osteoclastic function), and osteoblastic function, as assessed by an increase in serum osteocalcin (141) and alkaline phosphatase (142), which would predict increases in BMD during longer term treatment.…”

“…In these studies patients with spontaneous menstruations had normal BMD, while patients without menstruations had reduced BMD (260,261). Further, GH seems to improve BMD (139,140), although in these two small studies no untreated control group of girls with Turner syndrome was included, and the patients were followed for up to 2 years only. In a recent 7-year study with GH treatment given at three different doses (see above), where bone mineral density was studied by phalangeal radiographic absorptiometry, volumetric bone density was found to be normal or increased in a dose-dependent manner (146).…”