Adjunctive vitamin D for the treatment of active juvenile idiopathic arthritis: An open-label, prospective, randomized controlled trial

Abstract

Vitamin D has an important immunomodulatory effect, but no trial has examined the effect of boosting serum levels of 25-hydroxyvitamin D (25OHD) in individuals with juvenile idiopathic arthritis (JIA). The aim of the present study was to assess whether vitamin D supplementation reduced disease activity and adjusted/maintained bone mass in patients with active JIA. A 24-week randomized trial was undertaken at Children's Hospital of Chongqing Medical University. Treatment-naive patients with JIA were randomly assigned (1:1) to one of two groups: Standard treatment with high dose oral cholecalciferol [2,000 IU per day; experimental group (EG)] or without supplementation [control group (CG)]. The primary outcomes were the 27-joint Juvenile Arthritis Disease Activity Score (JADAS-27 score), the Z-score for bone mineral density (BMD), and serum levels of 25OHD. A per-protocol analysis set approach was used. The Mann-Whitney U test was the main tool used for data analysis. A total of 42 participants were assigned randomly to the EG (n=20) or the CG (n=22); of these, 36 (n=18 and n=18, respectively) were included in per-protocol analysis. After 24 weeks, the mean level of 25OHD in the EG was higher than that in the CG (P<0.05). At the end of the intervention, there were no clear differences between the two groups in terms of BMD or JADAS-27 score (both P>0.05). Cholecalciferol supplementation (2000 IU/day) for 24 weeks raised serum levels of 25OHD in JIA patients but did not reduce disease activity or improve BMD (registration no. ChiCTR-INR-16009235; Date of Registration: 2016-10-12).

Keywords: 25-hydroxyvitamin D; bone mineral density; disease activity; juvenile idiopathic arthritis; vitamin D.

Figure 1.

Serum 25OHD levels in the EG and CG. After 12 and 24 weeks of supplementation, serum 25OHD levels in EG patients were higher than those in CG patients (P<0.05). 25OHD, 25-hydroxyvitamin D; CG, control group; EG, experimental group; *P<0.05; EG vs. CG after 12 weeks; **P<0.05; EG vs. CG after 24 weeks.

Figure 2.

JADAS-27 scores for the EG and CG. There was no significant difference in the JADAS-27 scores for the two groups after 12 or 24 weeks of supplementation with 25OHD. 250HD, 25-hydroxyvitamin D; CG, control group; EG, experimental group; JADAS-27, 27-joint Juvenile Arthritis Disease Activity Score.

Figure 3.

Z-scores for bone mineral density for the EG and CG. There was no significant difference in the Z-scores for either group after 12 and 24 weeks of supplementation with 25OHD. 25OHD, 25-hydroxyvitamin D; CG, control group; EG, experimental group.