ESPE2024 Poster Category 1 GH and IGFs 2 (11 abstracts)
1Department of Endocrinology and Metabolic Diseases, Polish Mother's Memorial Hospital - Research Institute, Lodz, Poland. 2Department of Endocrinology and Metabolic Diseases, Medical University of Lodz, Lodz, Poland. 3Department of Pediatric Endocrinology, Medical University of Lodz, Lodz, Poland
Background: Growth hormone (GH) is a well-known factor affecting bone mineral density (BMD). Adults with GH-deficiency exhibit lower BMD, which improves with treatment. However, to date, little is known about the effects of GHD (growth hormone deficiency) on BMD as well as about BMD in idiopathic short stature (ISS) prepubertal children - who remain short, despite normal GH concentrations in stimulation testing.
Aim: The purpose of the study was to analyse selected serum markers of bone turnover (osteocalcin, beta crosslaps and sclerostin) in prepubertal children with GHD and ISS compared to a control group.
Materials and Methods: The study group consisted of 43 short children (height <-2.0 SD), 33 boys and 10 girls, aged 9.45±4.39. In each of group, two GH secretion stimulation tests were performed (after clonidine and after glucagon). Diagnosis of GHD was set in 20 children and ISS in 23 participants. There was no significant difference between groups according to age (9.78±4.29 years vs 9.91±4.49 years) and serum vitamin D3 levels. The control group consisted of 13 healthy children matched for age, gender and 25(OH)D. Serum levels of osteocalcin, beta crosslaps, sclerostin, vitamin D, PTH, calcium, TSH, FT4, IGF-1 and IGFBP3 were assessed in all participants.
Result: A significant positive correlation between IGF-1 concentration and each of the bone turnover markers, as well as between IGFBP3 concentration and sclerostin concentration was found. No such correlation was shown between maxGH (in stimulation tests), FT4, TSH, PTH or 25(OH)D concentrations. Reduced IGF-1 levels (<-1.0 SD) were observed in both children with GHD and ISS, with no difference between the groups. Significantly lower levels of osteocalcin (85.71±21.92 and 90.02±37.47 ng/ml, respectively) and sclerostin (28.11±5.36 and 25.90±9.14 pmol/l, respectively) were found in children with both GHD and ISS as compared to the control group (108.08±31.89 ng/ml for osteocalcin and 35.81±15.57 pmol/l for sclerostin) with comparable levels of 25(OH)D: 19.93±8.53 for GHD, 16.32±6.81 for ISS and 19.96±6.70 ng/ml for controls and PTH (13.62±5.89 for GHD, 18.68±8.10 for ISS, 11.97±8.05 pg/ml for controls). Beta crosslaps concentration did not differ between all groups.
Conclusions: Reduced IGF-1 are likely a crucial factor contributing to abnormal bone turnover in children with short stature.