Growth hormone (GH) treatment to final height in children with idiopathic short stature: evidence for a dose effect.
OBJECTIVE
To investigate in an open-label randomized study, the effect of two doses of growth hormone (GH) on final height and height velocity during the first 2 years of treatment of children with idiopathic short stature (mean baseline height standard deviation score [SDS] -3.2).


METHODS
Patients were treated with GH at 0.24 mg/kg/week, 0.24 mg/kg/week for the first year and at 0.37 mg/kg/week thereafter (0.24-->0.37), or 0.37 mg/kg/week. Final height was evaluated in 50 patients at study completion (mean treatment duration, 6.5 years).


RESULTS
Patients who received 0.37 mg/kg/week (n = 72) experienced a significantly greater increase in height velocity than those who received 0.24 mg/kg/week (n = 70) (treatment difference = 0.8 cm/year; P = .003) or 0.24-->0.37 mg/kg/week (n = 67) (treatment difference = 0.9 cm/year; P = .001). For the 50 patients for whom final height measurements were available, mean height SDS increased by 1.55, 1.52, and 1.85 SDS, respectively, for the three dose groups. For the primary comparison between the 0.37 mg/kg/week and 0.24 mg/kg/week dose groups, the mean treatment difference (adjusted for differences in baseline predicted height SDS) was 0.57 SDS (3.6 cm; P = .025). Mean overall height gains (final height minus baseline predicted height) were 7.2 cm and 5.4 cm for the 0.37 mg/kg/week and 0.24 mg/kg/week dose groups, respectively, without dose effects on safety parameters. Final height measurements were within the normal adult height range for 94% of patients randomized to 0.37 mg/kg/week who continued to final height.


CONCLUSIONS
GH treatment dose-dependently increases height velocity and final height in children with idiopathic short stature.
Wit
Jan M
JM
Leiden University Medical Center, Leiden, the Netherlands. j.m.wit@lumc.nl
Rekers-Mombarg
Lyset T M
LT
Cutler
Gordon B
GB
Crowe
Brenda
B
Beck
Tracy J
TJ
Roberts
Kristen
K
Gill
Anne
A
Chaussain
Jean-Louis
JL
Frisch
Herwig
H
Yturriaga
Rafael
R
Attanasio
Andrea F
AF
D000293:Adolescent; D000365:Age Determination by Skeleton; D001827:Body Height / Q000187:drug effects*; D001846:Bone Development / Q000187:drug effects; D002648:Child; D004305:Dose-Response Relationship, Drug; D005260:Female; D005500:Follow-Up Studies; D006130:Growth Disorders / Q000188:drug therapy*; D019382:Human Growth Hormone / Q000008:administration & dosage*; D006801:Humans; D008297:Male; D011994:Recombinant Proteins / Q000008:administration & dosage; D013997:Time Factors; D016896:Treatment Outcome
D011994:Recombinant Proteins; D019382:Human Growth Hormone