Growth Hormone Increases Final Height in Patients with Juvenile Idiopathic Arthritis: Data from a Randomized Controlled Study

Abstract

GH treatment stimulates growth in short children with juvenile idiopathic arthritis (JIA). The extent to which this therapy increases final height is not known. Thirty-one growth-retarded children with systemic and polyarticular idiopathic arthritis were enrolled in this controlled study. After a mean observational time of 8.4 yr, final height was reached in 13 patients (seven females and six males) treated with GH for a mean of 6.7 yr in a dose of 0.33 mg/kg body weight per week. Eighteen patients (12 females and six males) served as an untreated control group. Mean increment in height in the treatment group was 1.6 +/- 0.8 SD, whereas the patients of the control group lost 0.7 +/- 1.8 SD. Overall, mean final height in the treatment group was -1.6 SD and in the control group -3.4 SD. More GH-treated patients reached a final height within target height than untreated patients (11 of 13 vs. four of 18). Disease activity markers had a significant influence on height outcome. After adjustment for baseline and average disease activity, the difference between treatment and control group was still significant (mean 1.5 SD). Patients with a moderate overall disease activity profited most from GH treatment. No adverse events were noted throughout the study. Our data suggest that long-term GH therapy has a beneficial effect on growth and final height in the majority of growth retarded children with severe forms of JIA.