Table 3.
Impact of vitamin D supplementation on RA and JIA outcomes.
| Author et al., year | Country Type of study Study duration | Number of patients vs. control group (if any) F:M, Age (mean +/- SD) | Vitamin D dose | Impact on disease activity |
|---|---|---|---|---|
| RA | ||||
| Chandrashekara and Patted 2017 (52) | India; Randomized, open-label interventional study; 3 months | 149 RA patients 15.6:1 49 ± 12.1 |
60,000 IU/week for 6 weeks then 60,000 IU/month for 1 month | Mean DAS28-CRP decreased significantly: 3.68 ± 0.93 to 3.08 ± 1.11 (p = 0.002) |
| Dehghan et al., 2014 (53) | Iran RCT 6 months |
40 patients in the intervention arm vs. 40 in the placebo arm; 7:1 45 ± 8.66 vs. 42.7 ± 9.77 for case and control groups, |
50,000 IU/week | No significant difference in DAS28 between intervention and placebo group. No significant difference in flare rate between intervention (17.5%) and placebo (27.5%) group. |
| Yang et al., 2015 (54) | China RCT 24 months |
64 case group vs 88 control 6.8:1 44.2 ± 7.5 vs. 41.7 ± 8.6 |
Alfacalcidol 0.5 µg/day |
No significant difference in disease recurrence (based on DAS28 values) between treatment and non-treatment group. |
| Hansen et al., 2014 (55) | US RCT 12 months |
11 patients in the intervention arm vs. 11 in the placebo arm 0.83:1 63 ± 12 vs. 53 ± 11 |
Ergocalciferol 50,000 IU*3/week for 4 weeks, then 50,000 IU*2/month for 11 months |
No significant difference in DAS28 between placebo and treatment group. |
| Franco et al., 2017 (56) | Iran, China, US Systematic review and meta-analysis |
240 patients in the intervention arm vs. 410 patients in placebo arm | Various | No significant difference in DAS28 between placebo and treatment groups. |
| Adami et al., 2019 (57) | Italy Exploratory study 3 months |
61 RA patients 4.4:1 58 ± 12 |
100,000 IU/month vit D3 | Significantly decreased DAS28 scores in patients with 25(OH)D ≥20 ng/ml (p < 0.01) after 3 months. No significant decrease in patients with 25(OH)D <20 ng/ml after 3 months |
| JIA | ||||
| Tang et al., 2019 (58) | China Open-label, prospective RCT 24 weeks |
18 patients in the intervention arm vs. 18 in the control arm 1.8:1 7.6 ± 4.3 vs 6.3 ± 2.9 |
2,000 IU/day vit D3 | No significant decrease in disease activity |
DAS28, disease activity score assessing 28 joints; DAS28-CRP, disease activity score assessing 28 joints including C-reactive protein as inflammatory marker; JIA, juvenile idiopathic arthritis; RA, rheumatoid arthritis; RCT, randomized controlled trial; 25(OH)D, 25-hydroxy vitamin D.