The use of NOAC for atrial fibrillation in patients after biologic valvular replacement or valvuloplasty

Study type

• Study topic:
  Human medicinal product

  Disease /health condition
• Study type:
  Non-interventional study
• Scope of the study:
  Assessment of risk minimisation measure implementation or effectiveness

  Effectiveness study (incl. comparative)
• Data collection methods:
  Secondary use of data

Non-interventional study

• Non-interventional study design:
  Cohort

  Other
• Non-interventional study design, other:
  Register-based observational study, Non-randomized registry study

Study drug and medical condition

• Anatomical Therapeutic Chemical (ATC) code:
  (B01AF02) apixaban

  apixaban

  (B01AA03) warfarin

  warfarin
• Medical condition to be studied:
  Atrial fibrillation

Population studied

• Short description of the study population:
  The patient cohort will be identified using the SWEDEHEART national quality register and will include all patients treated with either biological valve surgery, transcatheter valve intervention, or valvuloplasty performed during 2010-2017.; ; Inclusion criteria; Patients must meet all of the following inclusion criteria to be eligible for inclusion in the study:; 1. > 18 years at discharge.; 2. Valvular disease requiring valve surgery, transcatheter valve intervention, or valvuloplasty; 3. Registred in SWEDEHEART for the index valve intervention; 4. Atrial fibrillation/flutter registred in SWEDEHEART or in the National Patient Register (NPR) before index intervention or during follow-up.; ; Exclusion criteria; Patients meeting any of the following criteria will not be included in the study:; 1. Treatment with a mechanical valve prosthesis; 2. Prescription of more than one type of OAC at discharge; 3. Death before discharge from the index valve intervention
• Age groups:
  • Adults (18 to < 46 years)
  • Adults (46 to < 65 years)
  • Adults (65 to < 75 years)
  • Adults (75 to < 85 years)
  • Adults (85 years and over)
• Special population of interest:
  Other
• Special population of interest, other:
  Atrial fibrillation patients
• Estimated number of subjects:
  5000

Study design details

• Main study objective:
  Describe the patterns of OACs and outcomes for patients with AF after biological valve surgery, transcatheter valve intervention or after valvuloplasty.
• Outcomes:
  To evaluate the association between apixaban versus warfarin treatment and the combination of all-cause death, stroke (ischemic and hemorrhagic), systemic embolization and major bleeding from 3 months post intervention to the end of follow up. To evaluate the association between apixaban versus warfarin treatment and the combination of all cause-death, stroke (ischemic and hemorrhagic), systemic embolization and major bleeding from hospital discharge post intervention to the end of follow up.To evaluate the separated endpoints, from hospital discharge post intervention and from 3 months post intervention.
• Data analysis plan:
  Step 1. To assess the feasibility, with respect to data quality, crude event counts by type of OAC and power estimation, to conduct a comparative analysis between apixaban and warfarin using the specified data. Step 2.( If the result of feasability assessment is positive, step 1)To evaluate the association between apixaban versus warfarin treatment on the composite endpoint of all-cause death, stroke (ischemic and hemorrhagic), systemic embolization and major bleeding from 3 months post intervention to the end of follow up.Methodology: To compare the risk of outcome events across the study cohorts, time to event analysis will be undertaken, using adjusted Cox regression models for intention to treat and time-varying Cox regression models for intention to treat and time-varying Cox regression models for on treatment analyses