Quality of Anticoagulation With Warfarin in Patient With Atrial Fibrillation for Secondary Stroke Prevention in Korea

The current study aims to assess the quality of anticoagulation with warfarin in real world practice of secondary stroke prevention in Korean patients with Atrial fibrillation (AF) and to explore predictors for poor International Normalized Range (INR) control.

Study Overview

• Status: Completed
• Conditions: Stroke; Atrial Fibrillation

Detailed Description

• To assess the quality of anticoagulation with warfarin in real world practice of Korea for secondary stroke prevention in patients with AF-related Cardioembolic (CE) stroke 1) who initiated warfarin therapy and treatment at least for more than 7 days of warfarin adjustment period (warfarin-initiated cohort), and 2) who initiated and maintained warfarin therapy at least for more than 90 days after the 7 days of warfarin adjustment period (long-term warfarin-treated cohort).
• To explore predictors for poor INR control.

• Study Type: Observational
• Enrollment (Actual): 1814

Contacts and Locations

Study Locations

• Korea, Republic of
  • Anyang, Korea, Republic of
    • Hallym University College of Medicine
  • Busan, Korea, Republic of
    • Dong-A University College of Medicine
  • Daegu, Korea, Republic of
    • Yeungnam University School of Medicine
  • Goyang, Korea, Republic of
    • Dongguk University Ilsan Hospital
  • Gwangju, Korea, Republic of
    • Chonnam National University Medical School
  • Ilsan, Korea, Republic of
    • Ilsan Paik Hospital Inje University
  • Incheon, Korea, Republic of
    • Inha University Hospital
  • Jeju, Korea, Republic of
    • Jeju National University Hospital, Jeju National University College of Medicine
  • Seongnam, Korea, Republic of
    • Seoul National University Bundang Hospital
  • Seoul, Korea, Republic of
    • Eulji General Hospital, Eulji University School of Medicine
  • Seoul, Korea, Republic of
    • Korea University College of Medicine
  • Seoul, Korea, Republic of
    • Samsung Medical Center, Sungkyunkwan University School of Medicine
  • Seoul, Korea, Republic of
    • Seoul Medical Center
  • Seoul, Korea, Republic of
    • Seoul National University College of Medicine
  • Seoul, Korea, Republic of
    • Soonchunhyang University College of Medicine
  • Seoul, Korea, Republic of
    • Soonchunhyang University
  • Seoul, Korea, Republic of
    • University of Ulsan College of Medicine
  • Seoul, Korea, Republic of
    • Yonsei University College of Medicine

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult; Older Adult
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Probability Sample

Study Population

Consecutive patients who admitted to 16 participating centers due to AF-related ischemic stroke between Jan 1, 2011 and Dec 31, 2012 and started warfarin therapy for secondary stroke prevention will be enrolled in this study. The number of patients is expected to be 2,217 for the warfarin-initiated cohort and 1,057 for the long-term warfarin-treated cohort.

Description

Inclusion Criteria:

Inclusion criteria for the warfarin-initiated cohort

1. Admission due to AF-related ischemic stroke
2. Initiation of warfarin therapy and treatment at least for more than 7 days of warfarin adjustment period
3. For TTR calculation, available consecutive INR values ≥3 after the 7 days of warfarin adjustment

Inclusion criteria for the long-term warfarin-treated cohort

1. Admission due to AF-related ischemic stroke
2. Long-term warfarin therapy at least for more than 90 days after the 7 days of warfarin adjustment period
3. For TTR calculation, available consecutive INR values ≥3 after the 7 days of warfarin adjustment
4. TTR evaluable days ≥ 90 days

Exclusion Criteria:

1. AF with mechanical valve
2. Enrollment in anticoagulation randomized clinical trial
3. Enrollment in studies affecting the target INR range.

Study Plan

How is the study designed?

Design Details

• Observational Models: Cohort
• Time Perspectives: Retrospective

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort
Short-term Warfarin-treated cohort; admission due to AF-related ischemic stroke (known AF or newly detected AF); for TTR calculation, the number of consecutive INR measurements ≥3 after the 7 days of warfarin adjustment; TTR evaluable days < 90 days
Long-term Warfarin-treated cohort; admission due to AF-related ischemic stroke (known AF or newly detected AF); long-term warfarin therapy at least for more than 90 days after the 7 days of warfarin adjustment period; for TTR calculation, the number of consecutive INR measurements ≥3 after the 7 days of warfarin adjustment; TTR evaluable days ≥ 90 days

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Time in TTR, the Percentage of Time in the Therapeutic Range of INR Between 2.0-3.0.	The primary outcome is TTR as measured by the percentage of time in the therapeutic range of INR between 2.0-3.0, using the Rosendaal linear interpolation method.	We will analyze INR data of patients who had AF-related ischemic stroke and were treated with warfarin therapy at least for more than 7 days of warfarin adjustment period. (The INR follow up duration: 1 ~ maximum 3 years)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Percentage of INR Values in the Therapeutic Range of 2.0-3.0: Numbers of INR Values Within the Therapeutic Range by the Total Numbers of INR Measured.	The secondary outcome is the percentage of INR values in the therapeutic range of 2.0-3.0: numbers of INR values within the therapeutic range divided by the total numbers of INR measured.	We will analyze INR data of patients who had AF-related ischemic stroke and were treated with warfarin therapy at least for more than 7 days of warfarin adjustment period. (The INR follow up duration: 1 ~ maximum 3 years)

Collaborators and Investigators

• Sponsor: Inje University
• Investigators: Principal Investigator: Keun-Sik Hong, MD, Phd, Department of Neurology, Ilsan Paik Hospital Inje University

Study record dates

Study Major Dates

• Study Start: June 1, 2015
• Primary Completion (Actual): October 1, 2016
• Study Completion (Actual): October 1, 2016

Study Registration Dates

• First Submitted: December 23, 2015
• First Submitted That Met QC Criteria: June 20, 2016
• First Posted (Estimate): June 23, 2016

Study Record Updates

• Last Update Posted (Actual): September 13, 2019
• Last Update Submitted That Met QC Criteria: August 8, 2019
• Last Verified: August 1, 2018

More Information

Terms related to this study

• Keywords: ischemic stroke; Wafarin; Cardioembolic (CE) stroke
• Additional Relevant MeSH Terms: Pathologic Processes; Heart Diseases; Cardiovascular Diseases; Vascular Diseases; Cerebrovascular Disorders; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Arrhythmias, Cardiac; Stroke; Atrial Fibrillation
• Other Study ID Numbers: Warfarin TTR-01

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: No