Objective: The objective of this study was to evaluate factors affecting adult height (AH) in patients with Turner syndrome treated with GH.
Design: The study design was a population-based cohort study.
Setting: The setting was The StaTur Study, a register of patients treated in France between 1986 and 1997, followed for a mean of 9.3 yr.
Patients: We followed 704 of the 891 eligible patients (79%) to AH.
Intervention: GH (0.8 +/- 0.2 IU/kg.wk; 0.26 +/- 0.06 mg/kg.wk; mean +/- sd) was administered for 5.0 +/- 2.2 yr. Puberty was classified as spontaneous (10%), spontaneous with secondary estrogens (13%), or induced (77%). Estrogen treatment was initiated at 15.0 +/- 1.9 yr of age in those with induced puberty.
Main outcome measure: The main outcome measure was multivariate analysis of AH after grouping potential predictors.
Results: The mean AH was 149.9 +/- 6.1 cm, 8.5 cm above projected height. The model explained 90% of the variance, with major effects of age at initiation and duration of treatment. Other factors included birth length, target height, bone age delay and weight at initiation of treatment, age at pubertal onset, GH dose, and number of injections per week. Age at introduction of estrogens was not a predictor, and the use of percutaneous vs. oral estrogens was associated with greater height (+2.1 cm; 95% confidence interval, 1.00-3.25).
Conclusions: Our results support the early initiation of GH treatment and induction of puberty at a physiological age to achieve optimal AH. They suggest that GH should be injected daily, and percutaneous estrogens used. These results should be considered in the context of the lack of demonstrable influence of AH on psycho-social outcomes, uncertainties regarding long-term safety, and treatment cost.