Sequential Expansion of Comparative Effectiveness of Oral Anticoagulants: A Cohort Study

Study type

• Study topic:
  Disease /health condition

  Human medicinal product
• 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

Study drug and medical condition

• Anatomical Therapeutic Chemical (ATC) code:
  (B01A) ANTITHROMBOTIC AGENTS

  ANTITHROMBOTIC AGENTS
• Medical condition to be studied:
  Atrial fibrillation

Population studied

• Short description of the study population:
  Patients ≥18 years with a diagnosis of non-valvular atrial fibrillation (NVAF) at risk for stroke (CHA2DS2-VASc score ≥ 1) who initiated treatment either with warfarin, dabigatran, rivaroxaban or apixaban between October 2010 and September 2015.
• 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:
  Non-valvular atrial fibrillation patients
• Estimated number of subjects:
  120000

Study design details

• Main study objective:
  Quantify associations between anticoagulant choice (warfarin and dabigatran) and the occurence of selected outcomes in patients with non-valvular atrial fibrillation at risk of stroke
• Outcomes:
  StrokeMajor bleeding, Stroke or systemic embolismSystemic embolismIschemic strokeHemorrhagic strokeStroke uncertain classificationTransient ischemic attackMyocardial infarctionVenous thromboembolismDVTPulmonary embolismMajor intracranial bleedingMajor extracranial bleedingMajor GI bleedingMajor upper GI bleedingMajor lower GI bleedingMajor urogenital bleedingMajor other bleeding
• Data analysis plan:
  After identifying initiators of warfarin or dabigatran with an existing diagnosis of non-valvular atrial fibrillation and at risk for stroke in two large US commercial claims databases we will use propensity score methods and time-to-event analyses to estimate the ratio in hazard rates for each of the outcomes of interest.