Vitamin D in Colombian patients with systemic lupus erythematosus and its correlation with disease activity

Introduction Patients with systemic lupus erythematosus (SLE) frequently present low levels of vitamin D. However, studies that have evaluated its association with disease activity have generated contradictory results. Methods A cross-sectional study was carried out on patients diagnosed with SLE in two hospitals in Manizales, Colombia. Disease activity was evaluated by the SLE disease activity index 2000 (SLEDAI-2K) and serum concentration of 25-hydroxyvitamin D (25(OH)D) was measured by chemiluminescence. The correlation analysis was accomplished with the Spearman correlation coefficient. Results The study included 51 patients. The median SLEDAI-2K score was 8 points. The mean serum level of 25(OH)D was 24.5 ng/ml. Of the participants, 37.3% had vitamin D insufficiency and 35.3% had deficiency. An inverse correlation was found between the levels of the 25(OH)D and the SLEDAI-2K score (r = -0.578,p < 0.001), being greater in late-onset lupus, with absence of polyautoimmunity and in patients using glucocorticoids. Conclusions Low levels of vitamin D are frequent in SLE, presenting an inverse correlation with the disease activity. This is influenced by the use of glucocorticoids, the present of late-onset lupus and the absence of polyautoimmunity.