title: A variant of IL6R is associated with the recurrence of atrial fibrillation after catheter ablation in a Chinese Han population.
abstract: BACKGROUND
  Recent studies have identified a variant, rs4845625, in the interleukin-6 receptor (IL6R) gene associated with Atrial Fibrillation (AF). Levels of circulating interleukin-6 and other proinflammatory molecules have consistently been associated with a risk for AF and its recurrence after catheter ablation. This study tested the hypothesis that variant rs4845625 is associated with AF recurrence after catheter ablation in a Chinese Han population.
  
  
  METHODS
  A total of 278 consecutive patients (mean age 59.4±11.5 years, 43% female) with paroxysmal (36.0%), persistent (59.7%), and permanent (4.3%) AF who underwent catheterablation from 2007-2011, were included in this study. Patients were monitored for 12 months for a recurrence of AF. The SNP rs4845625 was genotyped using high resolution melting analysis.
  
  
  RESULTS
  In our study cohort, an early recurrence of AF (ERAF), defined as a recurrence within the first 4 weeks, was observed in 42.8% of the patients, whereas late recurrence of AF (LRAF) (between 3 and 12 months) occurred in 25.9% of the patients. No significant differences in baseline clinical or echocardiographic characteristics were observed between patients with ERAF and LRAF. In contrast, the presence of the T allele of rs4845625 was associated with an increase in the risk for both ERAF (odds ratio [OR]: 1.84, 95% confidence interval [CI]: 1.31-2.59, p = 4.10×10-4) and LRAF (OR: 1.92, 95% CI: 1.30-2.81, p = 0.001). Furthermore, this association was significant after adjustments for age, sex, hypertension, diabetes and other risk factors. No significant relationship between rs4845625 and serum levels of IL6 was observed.
  
  
  CONCLUSIONS
  In this study, a variant of the IL6R gene, rs4845625, was found confer risk to AF recurrence after catheter ablation in a Chinese Han population. Our findings indicated that the IL6R pathway or inflammation may play important rols in the recurrence of AF after catheter ablation.
authors.affiliation: Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, Hubei, China.
authors.forename: Gang
authors.initials: G
authors.lastname: Wu
authors.affiliation: Department of Geriatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
authors.forename: Mian
authors.initials: M
authors.lastname: Cheng
authors.affiliation: Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, Hubei, China.
authors.forename: He
authors.initials: H
authors.lastname: Huang
authors.affiliation: Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, Hubei, China.
authors.forename: Bo
authors.initials: B
authors.lastname: Yang
authors.affiliation: Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, Hubei, China.
authors.forename: Hong
authors.initials: H
authors.lastname: Jiang
authors.affiliation: Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, Hubei, China.
authors.forename: Congxin
authors.initials: C
authors.lastname: Huang
mesh_terms: D000483:Alleles; D044466:Asian People / Q000235:genetics*; D001281:Atrial Fibrillation / Q000209:etiology / Q000235:genetics*; D017115:Catheter Ablation / Q000009:adverse effects*; D005006:Ethnicity / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D008297:Male; D008875:Middle Aged; D008957:Models, Genetic; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D019947:Receptors, Interleukin-6 / Q000235:genetics*; D012008:Recurrence
chemical_list: C508603:IL6R protein, human; D019947:Receptors, Interleukin-6