Following Patients on Warfarin Therapy to See if Differences in Hemorrhagic Complications Exist

This study has been completed.
Sponsor:
Information provided by:
Department of Veterans Affairs
ClinicalTrials.gov Identifier:
NCT00075985
First received: January 12, 2004
Last updated: January 20, 2009
Last verified: April 2007
  Purpose

This is a prospective observational cohort study that is in the process of enrolling and following patients on warfarin therapy by utilizing anticoagulation clinics in VA hospitals across the US. There are currently 14 sites actively enrolling patients in the study. For each octogenarian enrolled a randomly selected patient with atrial fibrillation (AF) younger than 80 years of age from the same clinic and receiving warfarin for approximately the same duration is enrolled.


Condition
Atrial Fibrillation

Study Type: Observational
Study Design: Time Perspective: Prospective
Official Title: CSP #716B - The 80+ Hemorrhagic Cohort Study

Resource links provided by NLM:


Further study details as provided by Department of Veterans Affairs:

Estimated Enrollment: 700
Study Start Date: May 2000
Estimated Study Completion Date: April 2006
Detailed Description:

Objectives: The primary objectives are: (1) to quantify the absolute risk of major hemorrhagic complications associated with anticoagulation for AF among octogenarians; (2) to determine if risk and severity of major hemorrhagic complications is increased in octogenarians compared with younger patients maintained on warfarin for AF after adjustment for potential confounders; (3) to explore predictors of major hemorrhagic complications among octogenarians maintained on warfarin for AF; and (4) to determine the effectiveness of utilizing the VA Intranet to collect and manage patient data in the conduct of longitudinal studies.

Research Plan: This is a prospective observational cohort study that is in the process of enrolling and following patients on warfarin therapy by utilizing anticoagulation clinics in VA hospitals across the US. There are currently 14 sites actively enrolling patients in the study. For each octogenarian enrolled a randomly selected patient with AF younger than 80 years of age from the same clinic and receiving warfarin for approximately the same duration is enrolled.

Methods: Baseline data is collected and prospective follow-up data is captured every 3 months. Based on their duration of previous warfarin therapy, octogenarians with AF are assembled into either a survivor or an inception cohort. For analysis, patients with two weeks or less of prior warfarin exposure constitute the inception cohort. The primary endpoint is major hemorrhage as defined by the Consensus Recommendations published by the American College of Chest Physicians. Data is being collected to allow for verification of fatal bleeds and verification of the resultant morbidity from non-fatal major bleeds. Endpoints will be adjudicated by hemostasis experts blinded to the age of the patient. Since this is an observational study, all reported events and deaths are not related to or the result of any study intervention. Data on development of new comorbidities, medications, average daily warfarin dose or discontinuation and degree of anticoagulation as measured by the International Normalized Ratio (INR) is also being collected.

All aspects of the study are being conducted through the VA Intranet. Participating sites utilize the Intranet to transmit baseline and follow-up data forms on study patients, removing the need for detailed paper correspondences. Sites also have the opportunity to view and edit previously submitted forms, view the study manual, download paper copies of data collection forms, and utilize the bulletin board to post questions or comments about the study. Site Investigators and Coordinators access the Intranet from terminals in their own facility and are then presented with a unique study menu and bulletin board. To prevent unauthorized access to the data, Site Investigators and Coordinators have each been assigned an Electronic Signature (login name and password) in order to access the data forms on the Intranet. All data entered is submitted directly into the study database, obviating the need for subsequent transcription of data and reducing the opportunity for errors. Additionally, electronic data collection is designed to reject forms when predefined critical fields have not been completed or when values fall outside of field parameters. Data verification is done in real-time such that a site coordinator entering an invalid value is required to either skip the field or re-enter the corrected data to proceed. This should greatly reduce the time consumed searching through patient records to retrieve data that was entered incorrectly originally.

Findings: Our goal is to enroll and follow a total of 700 patients over 5 years of recruitment. To date, 16 sites have enrolled a total of 502 patients into the study, 251 in the "survivor" cohort, 24 in the "inception" cohort, and 227 in the "control" cohort. There have been 66 reported deaths and 54 hemorrhagic events, 23 of which have been confirmed as major bleeds by the adjudication committee. The cohort to date has accumulated a total of 824 person-years of observation.

  Eligibility

Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Criteria
  • Patients with Atrial Fibrillation on Warfarin therapy currently being followed by a VA anticoagulation clinic
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT00075985

Locations
United States, Arizona
Carl T. Hayden VAMC
Phoenix, Arizona, United States, 85012
United States, Arkansas
Central Arkansas Veterans Healthcare System
Little Rock, Arkansas, United States, 72205
United States, Colorado
Denver VAMC
Denver, Colorado, United States, 80220
United States, Illinois
Hines VAMC
Hines, Illinois, United States, 60141
United States, Indiana
Roudebush VAMC
Indianapolis, Indiana, United States, 46202
United States, Iowa
Iowa City VAMC
Iowa City, Iowa, United States, 52246
United States, Louisiana
New Orleans VAMC
New Orleans, Louisiana, United States, 70146
United States, Massachusetts
Boston VA Medical Center
Boston, Massachusetts, United States, 02130
United States, Nebraska
Greater NE Healthcare System
Lincoln, Nebraska, United States, 68510
Omaha VAMC
Omaha, Nebraska, United States, 68105
United States, New Hampshire
VAMC Manchester
Manchester, New Hampshire, United States, 03104
United States, New York
Stratton VA Medical Center
Albany, New York, United States, 12208
Syracuse VA Medical Center
Syracuse, New York, United States, 13210
United States, Ohio
Dept. of Veterans Affairs Medical Center-Cincinnati
Cincinnati, Ohio, United States, 45220
United States, South Dakota
Royal C Johnson VAMC
Sioux Falls, South Dakota, United States, 57117
United States, Texas
Dallas VAMC
Dallas, Texas, United States, 75216
Central Texas Veterans Healthcare System
Temple, Texas, United States, 76504
Sponsors and Collaborators
  More Information

No publications provided

ClinicalTrials.gov Identifier: NCT00075985     History of Changes
Other Study ID Numbers: 716B
Study First Received: January 12, 2004
Last Updated: January 20, 2009
Health Authority: United States: Federal Government

Additional relevant MeSH terms:
Atrial Fibrillation
Arrhythmias, Cardiac
Cardiovascular Diseases
Heart Diseases
Pathologic Processes

ClinicalTrials.gov processed this record on October 30, 2014