Association between psoriasis and vitamin D: Duration of disease correlates with decreased vitamin D serum levelsAn observational case-control study

摘要

Recent literature has focused on the association of psoriasis with lower than normal or highly deficient vitamin D blood levels. To investigate the controversial association between psoriasis and vitamin D levels. From 2012 to 2014, 561 subjects were assessed, of which 170 had psoriasis , 51 had an autoimmune bullous, and 340 were healthy patients. Anagraphical data, 25(OH)D blood levels, and seasons of vitamin D levels assessments were recorded for each group. Vitamin D levels were significantly different among the 3 groups ( K = 151.284; P = .0001). Psoriatic patients had significantly lower serum levels of 25(OH)D (21.8 ng/mL) than healthy controls (34.3 ng/mL) (chi-square = 11.5; P = .0007). Patients with bullous diseases showed the lowest vitamin D mean values (18.2 ng/mL). The linear multiple regression model showed 25(OH)D levels to be influenced by age, season of blood vitamin D levels assessment, and psoriasis duration . These results confirm the reduced vitamin D levels in psoriatic patients when compared to healthy controls, and provide new evidence regarding the association of vitamin D levels and psoriasis duration . The limits of our study include its observational nature and the small number of patients undergoing biological immunosuppressive therapies.