MedWire News: Study results suggest that vitamin D deficiency may be more common in patients with chronic plaque psoriasis than in the general population.
The researchers say that the reason for the reduced levels of vitamin D observed in these patients is unclear, but that the findings are in agreement with prior studies that have reported vitamin D deficiency "in other chronic immune-mediated inflammatory skin diseases including atopic dermatitis, vitiligo, and chronic urticaria."
Writing in the British Journal of Dermatology, Paolo Gisondi (University of Verona, Italy) and colleagues carried out a cross-sectional study in 145 patients with chronic plaque psoriasis, 112 patients with rheumatoid arthritis (RA), and 141 healthy controls. The mean age of the participants was 53.9 years.
Gisondi and team measured 25-hydroxyvitamin D [25(OH)D], parathyroid hormone (PTH) and calcium serum levels in all the participants in the spring, summer, autumn, and winter of 2010.
They found that overall, vitamin D deficiency, defined as a 25(OH)D level below 20 ng/mL, was significantly more common in patients with psoriasis than in those with RA, or controls, at 57.8% versus 37.5% and 29.7%, respectively.
The prevalence of vitamin D deficiency was significantly higher in winter, particularly in those with psoriasis, with corresponding frequencies in the three groups of 80.9% versus 41.3% and 30.3%.
Of note, there were no significant differences in PTH or calcium levels between the three groups.
The researchers caution that the study is cross sectional and therefore causality cannot be assumed.
However, "observational studies in large cohorts have shown significant associations between low levels of 25(OH)D and increased risk of diabetes mellitus, metabolic syndrome and cardiovascular mortality." They suggest that this could be one reason for the association with psoriasis as it is also associated with these conditions.
A link with other autoimmune conditions and vitamin D deficiency has also been observed, so the team believe that this may also apply to psoriasis, but say that further research is needed to confirm and expand their findings.
MedWire (www.medwire-news.md) is an independent clinical news service provided by Springer Healthcare Limited. © Springer Healthcare Ltd; 2012
Free abstract
