Predictors of Treatment and the Comparative Clinical and Economic Outcomes among Non-Valvular Atrial Fibrillation Patients Treated versus Untreated with Oral
Anticoagulant Therapy (NVAF Diagnosed Untreated)

Study type

• Study topic:
  Human medicinal product

  Disease /health condition
• Study type:
  Non-interventional study
• Scope of the study:
  Disease epidemiology

  Effectiveness study (incl. comparative)

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

Non-interventional study

• Non-interventional study design:
  Cohort

Study drug and medical condition

• Medicinal product name:
  ELIQUIS
• Medical condition to be studied:
  Atrial fibrillation

Population studied

• Short description of the study population:
  Elderly patients (aged ≥65 years) will be required to have ≥1 inpatient or ≥ 2 outpatient medical claims (the 2 outpatient claims are ≥7 days apart) for AF during the identification period for the primary and secondary objectives. For the primary objective, two mutually-exclusive NVAF patient cohorts will be created: ever treated with OAC and nevertreated with OAC. For the secondary objective assessing clinical and healthcare utilization and costs, treatment status will be a time-varying covariate and ever-treated patients will contribute time-not-on-treatment to untreated effect.; ; Inclusion Criteria; 1) Patients had ≥1 inpatient claim or ≥2 outpatient claims (at least 7 days gap between the two outpatient claims) for AF (international classification of diseases, ninth revision, clinical modification [ICD-9-CM] code 427.31; ICD-10-CM: I480-I482, I4891) during 01JAN2013-31DEC2017. The first AF diagnosis claim dates during the identification period were designated as the index date24;; 2) Patients had 12-months of continuous health plan enrollment with medical and pharmacy benefits (Medicare Part A, B, and D) before the index date and 6-month continuous health plan enrollment with medical and pharmacy benefits (Medicare parts A, B, and D) after the index date;; 3) Patients had CHA2DS2-VASc score ≥2 during 12 months on or before the index date;; 4) Aged ≥65 years on the index date.; ; Exclusion Criteria; 1) Excluded patients with AF diagnosis prior to the index date;; 2) Excluded patients with medical claims indicating diagnosis of mitral valvular heart disease or valve replacement procedure (see Appendix) during the 12 months prior to or on the index date;; 3) Excluded patients who had a pharmacy claim for apixaban, dabigatran, edoxaban, rivaroxaban, or warfarin during the 12 months pre-index period.
• Age groups:
  • 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:
  1204507

Study design details

• Main study objective:
  1.Estimate patients ever-treated and never-treated with OACs and the predictors of OAC treatment among elderly Medicare NVAF patients. 2.Compare the risk of stroke/SE & major bleeding and related costs among elderly patients treated versus untreated with OACs in the Medicare NVAF population.
• Outcomes:
  Predictors of treatment, Major bleeding, Stroke/SE, Major bleeding related costs, Stroke/SE related costs/ All cause health care utilization, All cause costs
• Data analysis plan:
  means, medians, and standard deviations will be provided for continuous variables. When performing descriptive analysis of categorical data, numbers and percentages will be provided for dichotomous and polychotomous variables. Bivariate comparisons of baseline characteristics and outcomes measures will be provided. Appropriate tests (eg, t-test, chi-square test) will be used based on the distributions of the measures. The cumulative incidence rate for clinical outcomes (major bleeding, stroke/SE, and death) will be calculated. A logistic regression will be used to examine risk factors associated with OAC treatment (OAC, DOAC, or warfarin)/non-treatment with OACs and DOAC treatment/warfarin treatment.