Add chronic psoriasis to the list of inflammatory skin diseases that may be affected by vitamin D deficiency. According to a study in the British Journal of Dermatology, patients with psoriasis were much more likely to have the deficiency compared to healthy controls and even patients with rheumatoid arthritis-another condition believed to be influenced by vitamin D levels.
Italian academic researchers measured 25-hydroxyvitamin D levels in 145 patients with chronic plaque psoriasis, 112 patients with rheumatoid arthritis, and 141 healthy controls. Questionnaires provided estimates of typical sunlight received by each patient.
Independent of participant age, gender, calcium level, body mass index, parathyroid hormone, and season of the year, vitamin D deficiency was associated with psoriasis. Deficiency was observed in 57.8% of psoriasis patients compared to 37.5% of rheumatoid arthritis patients and 29.7% of healthy controls. When screened during winter, the association deepened: defiency in 80.9% of psoriasis patients compared to 41.3% of rheumatoid arthritis patients and 30.3% of healthy controls.
Vitamin D deficiency, according to the researchers, has been reported in several other inflammatory skin diseases, including atopic dermatitis, vitiligo, and chronic urticaria.