Hypo-vitaminosis D and its relevance to the stability of the immune system represent an interesting
investigational topic in the field of rheumatology.
Objectives: survey hypo-vitaminosis D and its relation to disease activity parameters in a population of patients
with autoimmune diseases.
Materials and methods: case control study including 70 patients: 30 patients with rheumatoid arthritis (RA), 30
patients with systemic lupus erythematosus (SLE) and 10 patients with ankylosing spondylitis (AS). In vitro
quantitative determination of serum 25-hydroxyvitamin D3 using the electro-chemi-luminescence immunoassay
"ECLIA" was done. Serum concentrations ≥ 30 ng/ml has been considered sufficient and levels between 11 ng/ml-29
ng/ml has been considered insufficient, whilst patients with levels ≤ 10 ng/ml has been considered deficient. Fifty
healthy control subjects were included.
Results: Hypo-vitaminosis D was reported in 91.4% of the patients vs. 68% of the control group. The mean
values of vitamin D in the population with AID was significantly lower than in controls (16.14 ± 9.32 ng/ml vs 24.61 ±
8.36 ng/ml, t=-5.05, P<0.01**, 95% CI=-12.31-5.31). The majority of patients (57.1%) had insufficiency vs 34.3%
with vitamin D deficiency. Vitamin D levels inversely correlated with the ESR (r=-0.23, P=0.04) and with the SLEDAI
score in SLE (r=-0.419, P=0.02). Regression analysis identified the presence of an autoimmune disease as a
potentially significant risk factor for vitamin D deficiency (P<0.001).
Conclusion: The study reported a higher prevalence of hypo-vitaminosis D with autoimmune diseases. Lower
levels of vitamin D correlated with higher ESR in all patients and with the SLEDAI score.