Serum 25-Hydroxyvitamin D, acute phase reactants and disease activity in rheumatologic diseases

BRANCE ML; BRUN LR; LARROUDE MS; SACNUN MP; AESCHLIMANN C; BERBOTTO G; PALATNIK M; CHAVERO I; SANCHEZ A

Congreso; American College of Rheumatology (ACR) Annual Meeting 2017; 2017

Background: Previous evidence indicates anassociation between vitamin D deficiency and autoimmune diseases. The aim ofthis study was to evaluate serum 25-hydroxyvitamin D (25OHD), acute phase reactants and disease activity in patients with rheumatologic diseases (RD). Methods: This retrospective study evaluated 173 patients with RD (94rheumatoid arthritis (RA), 18 spondyloarthropathies (SA), 61 collagenopathies(COL) (systemic lupus erythematosus, vasculitis, scleroderma, undifferentiated disease, superposition syndrome)and compared them with a control group (CG, n=121) matched by age (CG= 55.0±14.7 years; RD= 53.4±13.6, sex and body mass index (BMI). All patients were from Rosario(32º52´18´´S) and Buenos Aires (34º36´14´´S) cities. Exclusion criteria:supplementation with vitamin D, pregnancy, intestinal malabsorption, chronicliver or kidney disease, and cancer. Date are expressed as mean±SEM. Differences between groups wereanalyzed using the Mann-Whitney or Kruskal-Wallis tests. Correlations were performed with Spearman?s correlationtest. Univariate linear regression and logistic regression analysis wereperformed. Contingency tables were evaluated with c2 test. The difference was considered significant if p<0.05. Results: RDpatients had significant lower 25OHD levels as a control group (CG= 26.8±1.1 ng/ml; RD= 19.8±0.6 ng/ml; p<0.0001). Furthermore, all subgroups had lower 25OHD (RA=20.7±0.7 ng/ml, SA= 15.4±1.3 ng/ml, COL= 19.7±1.1 ng/ml). The OR of patients with RD being vitamin D deficient (25OHD<20 ng/ml) was 2.7 (95%CI 1.6 to 4.4) with a probability of 73%. Consistentwith 25OHD differences,significant lower serum calcium (CG= 9.33±0.04; RD= 9.14±0.08 mg/dl; p=0.0457) and higher PTH (CG= 39.72±2.37; RD= 49.93±3.34 pg/ml; p=0.0191) levels were found. No differencesin serum phosphate, urinary calcium and urinary deoxipiridinoline wereobserved. 25OHD significantly correlated with erythrocyte sedimentation rate(ERS) [r= -0.28; p=0.0017] as acute phase reactants. No differences was foundin reactive C-protein (RCP). Lower values of 25OHD were found at higher DAS-28(<3.2= 22.9 ng/ml; 3.2-5.1= 19.8 ng/ml; >5.1= 19.9 ng/ml; p=0.23) and HAQ-DI(0-1= 22.9 ng/ml; 2= 19.8 ng/ml; 3= 19.9 ng/ml; p=0.001). Activity scores inother RD couldn´t be analyzed because of the small number of patients. Age,BMI, presence of RD, RCP and HAQ-DI were significantly and inversely associatedwith 25OHD levels. BMI, presence of RD, ERS and RCP were significantly associatedwith vitamin D deficiency. Conclusion: Patients with RD have a high probability of being deficient in 25OHD. Low 25OHD levels are associated with high acute phasereactants in the whole group, and with high disease activity scores in RA patients.