Background: To assess effect of 1,25 dihydroxy vitamin D3 supplementation on pain relief in early rheumatoid arthritis (RA).
Materials and methods: An open-labeled randomized trial was conducted comparing 60,000 IU 1,25 dihydroxy vitamin D3 + calcium (1000 mg/day) combination [Group A] versus calcium (1000 mg/day) only [Group B], as supplement to existing treatment regimen in early RA. Primary outcome included (i) minimum time required for onset of pain relief (Tm) assessed through patients' visual analog scale (VAS); (ii) % change in VAS score from onset of pain relief to end of 8 weeks. Secondary outcome included change in disease activity score (DAS-28).
Results: At the end of 8-weeks, Group A reported 50% higher median pain relief scores (80% vs. 30%; P < 0.001) and DAS-28 scores (2.9 ± 0.6 vs. 3.1 ± 0.4; P = 0.012) compared to Group B; however, Tm remained comparable (19 ± 2 vs. 20 ± 2 days; P = 0.419). Occurrence of hypovitaminosis-D was lower (23.3%) compared to Indian prevalence rates and was a risk factor for developing active disease (Odds Ratio (OR) = 7.52 [95% Confidence Interval (CI) 2.67-21.16], P < 0.0001). Vitamin D deficiency was significantly (P < 0.001) more common in female gender, active disease, and shorter mean disease duration. Vitamin D levels were inversely correlated to disease activity as assessed by DAS-28 (r = -0.604; P < 0.001).
Conclusions: Vitamin-D deficiency is a risk factor for developing active disease in RA. Weekly supplementation of 60,000 IU of 1,25 dihydroxy vitamin D3 in early RA results in greater pain relief. The number needed to treat for this additional pain relief was 2.
Identifier: CTRI/2018/01/011532 (www.ctri.nic.in).
Keywords: 1,25 dihydroxy vitamin D3; early rheumatoid arthritis; pain relief; visual analogue scale.