Near Normalization of Final Height with Adapted Doses of Growth Hormone in Turner’s Syndrome

Abstract

An adapted GH dose regimen was evaluated in 14 untreated patients with Turner's syndrome. The initial GH dose (0.7 U/kg.BW) was increased by 0.7 U/kg.BW, up to a maximum of 2.1 U/kg.BW, when growth velocity (GV) declined to less than 200% of the pretreatment level. These patients were compared to a group of 17 patients with similar initial characteristics, who received a fixed dose of 0.9 U/kg.BW GH. Tolerance to both GH regimens was excellent. The adapted GH doses only partially prevented the waning effect observed with conventional doses of GH, and the initial goal of doubling GV was only achieved in 42% of the 112 patient-semesters. Doubling the GH dose from 0.7 to 1.4 U/kg.BW increased the GV by 1.6 +/- 1.8 cm/yr (P < 0.006); increasing the GH dose from 1.4 to 2.1 U/kg.BW increased GV by 0.8 +/- 1.3 cm/yr (P = NS). The overall height gain during the 4-yr trial was 25.6 +/- 3.9 cm in the adapted dose group and 21.8 +/- 3.9 cm in the conventional group (P < 0.02). Final height (FH) results were obtained in 12 of 14 patients in the adapted dose group and all 17 patients in the conventional group and compared to the predicted FH using Lyon's method. The estimated height benefit was 10.6 +/- 3.8 cm in the adapted dose group compared to 5.2 +/- 3.7 cm in the conventional group (P < 0.01). Eighty-three percent of the patients in the adapted dose group had an FH superior or equal to -2 SD score for the general population compared to 29% in the conventional group. In conclusion, a marked increment in the GH dose in girls with Turner's syndrome associated with a relatively late age at introduction of estrogen therapy brought 83% of the patients into the lower range of the normal height distribution of the general population.

Adult height in girls with Turner syndrome treated from before 6 years of age with a fixed per kilogram GH dose

“…Mean AH (cm) was also similar to that recorded in other studies, where patients commenced treatment at a more advanced age (21,22) and the per kilogram GH doses throughout study periods were not fixed. In other TS studies, the prevalence of treated patients with AH !K2 SDS ranged from 32% (23) to 64% (24), as in this study.…”

“…Although a physiological decline over time in growth response to treatment has been reported in TS (2,18,24,26), the progressive increments of GH doses, aiming to counteract the gradual waning effect of this therapy, were proposed (2). Nevertheless, the waning effect observed with conventional GH doses has been reported to be only partially prevented by incrementing GH doses (24), and incremental dosing after the first year may not completely reverse it (18).…”

“…Nevertheless, the waning effect observed with conventional GH doses has been reported to be only partially prevented by incrementing GH doses (24), and incremental dosing after the first year may not completely reverse it (18).…”

Estatura final (EF) em síndrome de Turner (ST): experiência de 76 casos acompanhados na Unidade de Endocrinologia Pediátrica do Hospital de Clínicas da Universidade Federal do Paraná

“…Embora a idade cronoló-gica ao início do tratamento esteja correlacionada com uma maior estatura final (15,16,19,21,33,35), neste estudo não observamos essa correlação.…”

“…Inúme-ros trabalhos envolvendo essa combinação têm sido publicados desde meados dos anos 1990 (8,(13)(14)(15)(16)(17)(18)(19)(20)(21)(22) …”