Efficacy and Safety of Vitamin D Supplementation in Patients With Systemic Lupus Erythematosus: A Meta-analysis of Randomized Controlled Trials.

BACKGROUND

The efficacy of vitamin D supplementation in patients with systemic lupus erythematosus (SLE) remains uncertain. This meta-analysis aimed to systematically evaluate the efficacy and safety of vitamin D supplementation in patients with SLE.

MATERIALS AND METHODS

Randomized controlled trials (RCTs) were searched in PubMed, Embase, Cochrane CENTRAL and Web of Science databases. The retrieved studies were subjected to meta-analysis using the fixed-effect or random-effect model.

RESULTS

Five eligible RCTs enrolling 490 participants were included. Compared to the placebo treatment, vitamin D supplementation significantly increased the level of serum 25-hydroxyvitamin D (25(OH)D) (5 trials, 490 participants: standard mean difference (SMD) = 2.072, 95% CI: 1.078-3.066, P < 0.001). The pooled result from 2 RCTs showed that vitamin D supplementation decreased the fatigue severity scale scores in patients with SLE (2 trials, 79 participants: SMD = -1.179, 95% CI: -1.897 to -0.460, P = 0.001). The SLE disease activity index scores and positivity of anti-double-stranded DNA antibodies (anti-dsDNA) did not differ significantly (4 trials, 223 participants: SMD = -0.507, 95% CI: -1.055-0.041, P = 0.070; 3 trials, 361 participants: Risk ratio = 0.880, 95% CI: 0.734-1.054, P = 0.165) between the vitamin D supplementation group and the placebo treatment group. None of the included studies reported severe adverse events associated with vitamin D supplementation.

CONCLUSIONS

This meta-analysis suggested that vitamin D supplementation is effective in increasing the serum 25(OH)D levels, may improve fatigue, and is well-tolerated in patients with SLE, however, it does not seem to have significant effects in decreasing the positivity of anti-dsDNA and disease activity.