Pediatric Rheumatology Online Journal → June 2003 → Medical Treatment → Anti-tumor necrosis factor therapy→ Abstract #54

IMPROVED HEIGHT DEVELOPMENT IN CHILDREN WITH JUVENILE IDIOPATHIC ARTHRITIS TREATED WITH ETANERCEPT

M. Rygg, R. Svendsrud, N. T. Songstad, E. B. Nordal

¹Department of Laboratory Medicine, Childrens and Womens Health, The Norwegian University of Science and Technology, Trondheim, Norway; ²Department of Pediatrics, University Hospital of Northern Norway, Tromsoe, Norway

Growth impairment has been described in patients with juvenile idiopathic arthritis (JIA). Both the direct action of the underlying disease, nutritional abnormalities and prolonged corticosteroid usage, may contribute to growth impairment. We have studied the growth development of all children with JIA treated with etanercept and living in two areas in Norway. Height was measured at treatment start, after one and two years of treatment. Using national height standards in a specially designed program (Growth Vision, Novo Nordic), height measurements of each child were converted into age- and sex-specific Z scores (standard deviation scores, SDS). Changes in height Z score were analyzed using Wilcoxon signed ranks test. Of the 17 children treated with etanercept 5 children treated for less than one year, were excluded. The remaining 12 children (age at etanercept start 3-17 years, median 11) were treated for 14-33 months, median 25. One year after treatment start, 8 of 12 children had a positive height development. Mean height Z score at treatment start was -1.4, after one year -1.2 (p=0.03). After two years of treatment, 7 of 9 children had a positive height development. Mean height Z score at treatment start of these 9 was -1.7, after one year -1.5 (p= 0.09) and after two years -1.3 (p=0.02).
In this study we show that prolonged treatment with etanercept has a positive impact on height development in children with JIA. Some of the positive effect on growth may be due to the reduction or discontinuation in corticosteroids seen after treatment start with etanercept. However, also children who did not receive corticosteroids before etanercept start, showed a positive height development during treatment, suggesting a favorable effect on other growth-related factors. Etanercepts positive effect on height development in children with JIA needs further studies.