Vitamin D3 supplementation (100,000 IU per month) is not recommended as a treatment for mild psoriasis, according to a recent study. Participants with psoriasis in a large, randomized, controlled trial examining the effect of vitamin D3 supplementation in adults aged 50-84 years, participated in a psoriasis sub-study over 12 months. The primary outcome was the Psoriasis Area and Severity Index (PASI) and secondary outcomes were Physicians Global Assessment (PGA), Dermatology Life Quality Index (DLQI), and Psoriasis Disability Index (PDI). 23 subjects were allocated to vitamin D and 42 to placebo; mean (SD) baseline 25-hydroxyvitamin D was 65.7 (25.7) nmol/L. Researchers found:
- There was no significant difference at baseline between the 2 groups.
- There were no significant differences between the groups in all of the psoriasis outcome measures.
- Mean scores at 12 months for the placebo vs vitamin D groups: PASI 2.2 [1.4, 3.0] vs 2.1 [1.0, 3.2]; PGA 1.4 [1.1, 1.7] vs 1.5 [1.1, 1.9]; PDI 2.1 [0.9, 3.2] vs 1.9 [0.4, 3.4]; and DLQI 2.5 [1.4, 3.6] vs 2.0 [0.5, 3.4].
Jarrett P, Camargo Jr CA, Coomarasamy C, Scragg R. A randomized, double-blind, placebo-controlled trial of the effect of monthly vitamin D supplementation in mild psoriasis. [Published online ahead of print August 29, 2017]. J Dermatolog Treat. doi:10.1080/09546634.2017.1373735.
Although topical therapy with vitamin D analogues are indicated for the treatment of psoriasis, this study demonstrated that supplementation with Vitamin D3 did not exhibit significant improvement in PASI scores, PGA, and DLQI in patients with mild psoriasis. The limitation in this study was that enrolled patients had mild psoriasis and changes in lower PASI scores from baseline are not as sensitive compared to higher baseline PASI scores. Several decades ago, vitamin D3 supplementation was used to treat psoriasis. However extremely high doses were utilized and there were severe adverse events, such as tetany and hypercalcemia. —Paul S. Yamauchi, MD, PhD