Correlation between plasmatic levels of vitamin D and PASI score.

BACKGROUND: Psoriasis is a common, inflammatory, chronic, relapsing skin disease. The pathogenesis is multifactorial and it is involved both innate and acquired immunity. Several studies have shown the important role of vitamin D in the pathogenesis of this disorder. In this study we have evaluated a possible correlation between vitamin D and clinical severity of psoriasis calculated using the Psoriasis Area Severity Score (PASI) score. METHODS: In this case control study we included 141 Caucasian subjects affected by moderate to severe psoriasis and 62 healthy controls. We have calculated PASI score and serum levels of vitamin D. RESULTS: Psoriatic patients had significantly lower serum levels of 25(OH)D than healthy controls. Using no parametric Spearman's coefficient test between serum levels of vitamin D and the PASI score we found a statistical significant correlation. However, the statistical significance was not reached analyzing separately the patients with psoriatic arthritis, while it was confirmed for patients without an articular involvement. CONCLUSIONS: The present study confirm that serum levels of vitamin D are significantly lower in psoriatic patients and correlate with the clinical severity of psoriasis; these data suggest that psoriatic patients could be screened for vitamin D insufficiency for a more comprehensive management.