Serum 25‐hydroxy vitamin D level in patients with pemphigus and its association with disease severity

Summary Background There is a growing number of studies suggesting a key role for vitamin D in the pathogenesis and progression of autoimmune disorders. Aim To determine the serum levels of 25‐hydroxy vitamin D [25( OH )D] in patients with pemphigus and association of 25( OH )D with clinical features. Methods We enrolled 52 patients with pemphigus and 56 age‐ and sex‐matched healthy controls ( HC s). Only patients newly diagnosed with pemphigus or patients who had relapsed after discontinuing their treatment for > 6 months were included. Serum 25( OH )D and parathyroid hormone ( PTH ) levels were measured. Data on demographics, body mass index ( BMI ), disease severity (based on Pemphigus Area and Activity Score; PAAS ) and involved surface body area ( BSA ) were obtained. Results Suboptimal levels of vitamin D (< 30 ng/ mL ) were observed in 78.8% and 91.0% of patients and HC s, respectively ( P  = 0.13). Univariate and multivariate ordinal logistic regression models showed that low vitamin D status was more likely to occur in patients with higher BSA ( OR  = 1.07, 95% CI 1.01–1.13) and those with higher cutaneous ( OR  = 1.36, 95% CI 1.11–1.66) and total ( OR  = 1.24, 95% CI 1.08–1.41) PAAS. However, there was no significant association between vitamin D levels and presence of pemphigus, season of sampling, age, BMI or smoking habit. Conclusion Vitamin D deficiency is common both in patients with pemphigus and in HC s. Patients with more severe disease (higher PAAS ) are likely to have lower vitamin D levels.