Serum calcification propensity is independently associated with disease activity in systemic lupus erythematosus

• Published in: PloS one Vol. 13; no. 1; p. e0188695
• Main Authors: Dahdal, Suzan, Devetzis, Vasilios, Chalikias, George, Tziakas, Dimitrios, Chizzolini, Carlo, Ribi, Camillo, Trendelenburg, Marten, Eisenberger, Ute, Hauser, Thomas, Pasch, Andreas, Huynh-Do, Uyen, Arampatzis, Spyridon
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 24.01.2018; Public Library of Science (PLoS)
• Subjects: Analysis; Atherosclerosis; Autoimmune diseases; Biology and Life Sciences; Biomarkers; Blood tests; Calcification; Calcification (Physiology); Chronic conditions; Complications; Complications and side effects; Creatinine; Democritus (460?-370?); Diagnosis; Diagnostic systems; Health aspects; Health risk assessment; Hemoglobin; Hemoglobins; Lupus; Medicine and Health Sciences; Mortality; Nephelometry; Patients; Rheumatology; Risk factors; Risk groups; Systemic lupus erythematosus; Greece; Thrace; Switzerland
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0188695

Systemic lupus erythematosus (SLE) is associated with severe cardiovascular complications. The T50 score is a novel functional blood test quantifying calcification propensity in serum. High calcification propensity (or low T50) is a strong and independent determinant of all-cause mortality in various patient populations. A total of 168 patients with ≥ 4 American College of Rheumatology (ACR) diagnostic criteria from the Swiss Systemic lupus erythematosus Cohort Study (SSCS) were included in this analysis. Serum calcification propensity was assessed using time-resolved nephelometry. The cohort mainly consisted of female (85%), middle-aged (43±14 years) Caucasians (77%). The major determinants of T50 levels included hemoglobin, serum creatinine and serum protein levels explaining 43% of the variation at baseline. Integrating disease activity (SELENA-SLEDAI) into this multivariate model revealed a significant association between disease activity and T50 levels. In a subgroup analysis considering only patients with active disease (SELENA-SLEDAI score ≥4) we found a negative association between T50 and SELENA-SLEDAI score at baseline (Spearman's rho -0.233, P = 0.02). Disease activity and T50 are closely associated. Moreover, T50 levels identify a subgroup of SLE patients with ongoing systemic inflammation as mirrored by increased disease activity. T50 could be a promising biomarker reflecting SLE disease activity and might offer an earlier detection tool for high-risk patients.