title: Elevated IL-1β levels in anti-Ro/SSA connective tissue diseases patients with prolonged corrected QTc interval.
abstract: OBJECTIVE
  Patients with systemic lupus erythematosus (SLE) and primary Sjögren's syndrome (pSS) have increased IL-1β levels. IL-1β and other pro-inflammatory cytokines have a modulating activity on cardiac ion channels and have been associated with increased arrhythmic risk in rheumatoid arthritis patients. Likewise, adult patients with connective tissue diseases (CTDs) may have prolonged QTc intervals associated with the presence of anti-Ro/SSA antibodies. Our objective was to evaluate the presence of serum IL-1β in subjects with CTDs, in relation to the presence of anti-Ro/SSA antibodies and QTc interval duration.
  
  
  METHODS
  12-lead electrocardiograms (ECG) were performed and blood was withdrawn, measuring electrolytes, IL-1β anti-Ro/SSA antibodies by ELISA in 73 patients with CTDs.
  
  
  RESULTS
  55 patients were anti-Ro/SSA positive and 18 were anti-Ro/SSA negative. Patients with anti-Ro/SSA positive antibodies had a significantly greater median IL-1β serum level: 7.29 (range: 0.17-17.3 pg/ml) compared to patients with anti-Ro/SSA negative antibodies whose median was: 1.67 (range 0.55-4.12 pg/ml) p<0.001. The mean QTc interval values obtained in both groups were not significantly different (417.7±23.1 vs. 414.7±21.2, p=0.63). The QTc interval was prolonged in 11 (20%) patients, who were all anti-Ro/SSA positive versus 0 (0 %) in anti-Ro/SSA negative patients p=0.05. Median IL-1β levels were: 8.7 (range: 2.69-15.1 pg/ml) in patients with prolonged QTc interval versus median: 5.0 (range: 0.17-17.3 pg/ml) in those with normal QTc interval values (<440ms) p=0.006.
  
  
  CONCLUSIONS
  IL-1β is elevated in patients with CTDs that have both anti-Ro/SSA antibodies and prolonged QTc intervals.
authors: Rheumatology and Immunology Section, Department of Internal Medicine, CEMIC, University of Buenos Aires, Argentina.
authors: Cecilia N
authors: CN
authors: Pisoni
authors: Pharmacology Unit, Dentistry School, University of Buenos Aires, and National Research Council of Argentina (CONICET), Buenos Aires, Argentina.
authors: Silvia
authors: S
authors: Reina
authors: Cardiology Section, Department of Internal Medicine, CEMIC, University of Buenos Aires, Argentina.
authors: Diego
authors: D
authors: Arakaki
authors: Rheumatology and Immunology Section, Department of Internal Medicine, CEMIC, University of Buenos Aires, Argentina.
authors: Alicia
authors: A
authors: Eimon
authors: Rheumatology and Immunology Section, Department of Internal Medicine, CEMIC, University of Buenos Aires, Argentina.
authors: Carolina
authors: C
authors: Carrizo
authors: Pharmacology Unit, Dentistry School, University of Buenos Aires, and National Research Council of Argentina (CONICET), Buenos Aires, Argentina.
authors: Enri
authors: E
authors: Borda
mesh_terms: D000200:Action Potentials; D000328:Adult; D000974:Antibodies, Antinuclear / Q000097:blood*; D001145:Arrhythmias, Cardiac / Q000097:blood* / Q000175:diagnosis / Q000276:immunology / Q000503:physiopathology; D015415:Biomarkers / Q000097:blood; D003240:Connective Tissue Diseases / Q000097:blood* / Q000175:diagnosis / Q000276:immunology; D004562:Electrocardiography; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology*; D006801:Humans; D053583:Interleukin-1beta / Q000097:blood*; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012307:Risk Factors; D015854:Up-Regulation
chemical_list: D000974:Antibodies, Antinuclear; D015415:Biomarkers; C508585:IL1B protein, human; D053583:Interleukin-1beta; C035356:SS-A antibodies