title: Short-Term Risk of Bleeding During Heparin Bridging at Initiation of Vitamin K Antagonist Therapy in More Than 90 000 Patients With Nonvalvular Atrial Fibrillation Managed in Outpatient Care.
abstract: Several studies have recently examined the risks of bleeding and of ischemic stroke and systemic embolism associated with perioperative heparin bridging anticoagulation in patients with nonvalvular atrial fibrillation. However, few studies have investigated bridging risks during vitamin K antagonist initiation in outpatient settings.
  
  
  
  A retrospective cohort study was conducted on individuals starting oral anticoagulation between January 2010 and November 2014 for nonvalvular atrial fibrillation managed in outpatient care and identified from French healthcare insurance. Bleeding and ischemic stroke and systemic embolism events were identified from the hospitalization database. Adjusted hazard ratios with 95% CI were estimated using Cox models during the first and 2 following months of anticoagulation. Of 90 826 individuals, 30% had bridging therapy. A total of 318 (0.35%) cases of bleeding and 151 (0.17%) ischemic stroke and systemic embolism cases were identified during the first month of follow-up and 231 (0.31%) and 122 (0.16%) during the 2 following months, respectively. At 1 month of follow-up, the incidence of bleeding was higher in the bridged group compared with the nonbridged group (0.47% versus 0.30%; P<0.001), and this increased risk persisted after adjustment for covariates (hazard ratio=1.60; 95% CI, 1.28-2.01). This difference disappeared after the first month of treatment (0.93; 0.70-1.23). No significant difference in the occurrence of ischemic stroke and systemic embolism was observed either at 1 month of follow-up or later.
  
  
  
  At vitamin K antagonist initiation for nonvalvular atrial fibrillation managed in ambulatory settings, bridging therapy is associated with a higher risk of bleeding and a similar risk of arterial thromboembolism compared with no bridging therapy.
authors: Department of Epidemiology of Health Products, French National Agency for Medicines and Health Products Safety (ANSM), Saint-Denis, France kim.bouillon@ansm.sante.fr.
authors: Kim
authors: K
authors: Bouillon
authors: Department of Epidemiology of Health Products, French National Agency for Medicines and Health Products Safety (ANSM), Saint-Denis, France.
authors: Marion
authors: M
authors: Bertrand
authors: Department of Cardiovascular, Thrombosis, Metabolism and Obesity, French National Agency for Medicines and Health Products Safety (ANSM), Saint-Denis, France.
authors: Lotfi
authors: L
authors: Boudali
authors: Paris Sud-XI University, Villejuif, France.
authors: Pierre
authors: P
authors: Ducimetière
authors: Department of Epidemiology of Health Products, French National Agency for Medicines and Health Products Safety (ANSM), Saint-Denis, France.
authors: Rosemary
authors: R
authors: Dray-Spira
authors: Department of Epidemiology of Health Products, French National Agency for Medicines and Health Products Safety (ANSM), Saint-Denis, France.
authors: Mahmoud
authors: M
authors: Zureik
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000553:Ambulatory Care; D000704:Analysis of Variance; D000925:Anticoagulants / Q000009:adverse effects*; D001281:Atrial Fibrillation / Q000188:drug therapy*; D006470:Hemorrhage / Q000139:chemically induced*; D006495:Heparin, Low-Molecular-Weight / Q000009:adverse effects*; D006801:Humans; D008875:Middle Aged; D012307:Risk Factors; D014812:Vitamin K / Q000037:antagonists & inhibitors*; D055815:Young Adult
chemical_list: D000925:Anticoagulants; D006495:Heparin, Low-Molecular-Weight; D014812:Vitamin K
keywords: anticoagulant; arterial thrombosis; bleeding; heparin bridging; nonvalvular atrial fibrillation; vitamin K antagonist