Association of Vitamin D Deficiency with Psoriasis and Metabolic Syndrome: A Case-Control Study in Indian Patients

BACKGROUND: Substantial evidence suggests a higher risk of metabolic syndrome as a result of persistent inflammation in patients with psoriasis. Psoriasis may also be associated with vitamin D deficiency. AIM: To correlate vitamin D deficiency with psoriasis and metabolic syndrome. MATERIALS AND METHODS: Serum vitamin D levels were quantified, and metabolic syndrome was assessed in 42 cases whose psoriasis severity had been measured by PASI and in an equal number of age/gender-matched controls. The resultant data were analyzed statistically. The odds ratio was calculated wherever applicable and a two-tailed P < 0.05 was considered statistically significant. RESULTS: Vitamin D deficiency (<20 ng/ml) occurred in 43 subjects [(51.19%); 26 (62%), patients and 17 (40.4%), controls] and was statistically significant in patients (OR: 2.39, P = 0.044) though lacking correlation with disease severity. Metabolic syndrome seen in 25 (30%) subjects—15 (36%) patients and 10 (24%) controls—emerged to be significant (OR: 3.71, P = 0.047) in cases with vitamin D deficiency. Hypertension—observed in 31 (37%) subjects; 18 (43%) cases, 9 each (21.4%) with/without metabolic syndrome and 13 (31%) controls, 7 (16.6%) with and 6 (14.3%) without metabolic syndrome (P = 0.25)—correlated independently with vitamin D deficiency in patients (P = 0.009). CONCLUSIONS: Despite limitations of small sample size and observational nature, our study—probably the first such hereto from India—showed statistically significant associations between vitamin D deficiency, metabolic syndrome, and hypertension in patients with psoriasis. Future larger studies are needed for strengthening this evidence prior to the recommendation of its clinical application in the optimum management of patients.