25-hydroxyvitamin D3 Levels and Their Clinical Associations in a Polish Cohort of Systemic Sclerosis Patients: A Cross-Sectional Study

Vitamin D exhibits immunomodulatory effects in autoimmune diseases. We aimed to evaluate the associations of vitamin D levels with clinical and laboratory features of systemic sclerosis (SSc) in a Polish cohort. The study was prospective in design. SSc patients who met ACR-EULAR 2013 criteria underwent comprehensive clinical and laboratory investigations using the European Scleroderma Trials and Research group (EUSTAR) methodology. We assessed patients' sera for 25(OH)D3 using a radioimmunoassay, and the cutoff value for vitamin D deficiency was set at 20 ng/mL. Statistical analyses were performed using the Mann-Whitney U test, the Fisher's exact, and the Spearman's rho, where appropriate, with a significance threshold set at 0.05. We recruited 68 SSc patients (85% female). The mean 25(OH)D3 level was 21.6 +/- 10 ng/mL, and 50% of subjects (n = 34) presented vitamin D deficiency (mean 13.7 +/- 3.9 ng/mL). Vitamin D-deficient SSc patients exhibited higher prevalence of arterial hypertension (p = 0.002), proteinuria (p = 0.002), and lung fibrosis (p = 0.032), as well as higher CRP (p = 0.035). The modified Rodnan skin score correlated negatively with 25(OH)D3 in diffuse cutaneous SSc (dcSSc). We found no correlation with the disease duration, age, joints, and the heart. Vitamin D deficiency was common in the studied population of Polish SSc patients and was associated with arterial hypertension, proteinuria, lung involvement, and increased CRP.

Automated summary

This study evaluated the associations between vitamin D levels and clinical and laboratory features of systemic sclerosis (SSc). The study found that vitamin D deficiency was associated with arterial hypertension, proteinuria, lung involvement, and increased CRP in SSc patients.