Vitamin-D levels were determined in 176 primary SS patients and 163 matched healthy volunteers utilizing the LIAISON chemiluminescent immunoassays (DiaSorin-Italy). A correlation between vitamin-D levels and clinical and serological manifestations of SS was performed.
Mean vitamin-D levels were comparable between SS patients and control 21.2?¡À?9.4?ng/ml and 22.4?¡À?10?ng/ml, respectively. Peripheral neuropathy was diagnosed in 23 % of SS patients and associated with lower vitamin-D levels (18.6?¡À?5.5?ng/ml vs. 22.6¡À8?ng/ml (p?=?0.04)). Lymphoma was diagnosed in 4.3 % of SS patients, who had lower levels of vitamin-D (13.2?¡À?6.25?ng/ml), compared to SS patients without lymphoma (22?¡À?8?ng/ml), (p?=?0.03). Other clinical and serological manifestations did not correlate with vitamin-D status.
In this study, low levels of vitamin-D correlated with the presence of peripheral neuropathy and lymphoma among SS patients. The link between vitamin-D and neuropathy or lymphoma was reported in other conditions, and may support a role for vitamin-D in the pathogenesis of these processes. Plausible beneficial effect for vitamin-D supplementation may thus be suggested.