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Assessing the Ability of Warfarin Treated Patients to Predict Their INR

Assessing the Ability of Warfarin Treated Patients to Predict Their INR

Status
Completed
Phases
Unknown
Study type
Observational
Source
ClinicalTrials.gov
Registry ID
NCT02764112
Enrollment
87
Registered
2016-05-06
Start date
2015-10-31
Completion date
2016-07-31
Last updated
2019-06-27

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Atrial Fibrillation

Keywords

warfarin

Brief summary

ASSESSING THE ABILITY OF WARFARIN TREATED PATIENTS TO PREDICT THEIR INR Kathleen McNamara, James Hoehns, Matthew Witry The international normalized ratio (INR) is the accepted lab test used to measure the intensity of warfarin effect. The conventional wisdom is that patients receiving warfarin are unable to correctly determine, in the absence of an INR result, whether or not they are therapeutic at any given time. Some warfarin treated patients express that they have insight into what their INR result will be. Various patient related factors may contribute to these opinions. Our objective is to assess how accurately patients can guess their INR result before it is obtained and to describe factors which inform their opinion of what their INR will be.

Detailed description

ASSESSING THE ABILITY OF WARFARIN TREATED PATIENTS TO PREDICT THEIR INR Kathleen McNamara, James Hoehns, Matthew Witry The international normalized ratio (INR) is the accepted lab test used to measure the intensity of warfarin effect. The conventional wisdom is that patients receiving warfarin are unable to correctly determine, in the absence of an INR result, whether or not they are therapeutic at any given time. Some warfarin treated patients express that they have insight into what their INR result will be. Various patient related factors may contribute to these opinions. Our objective is to assess how accurately patients can guess their INR result before it is obtained and to describe factors which inform their opinion of what their INR will be. In this prospective study, the investigators will enroll warfarin treated patients from 7 anticoagulation clinics in Iowa. Inclusion criteria are: age ≥18 years, warfarin use ≥60 days, INR goal of 2.0-3.0 or 2.5-3.5, expected warfarin use \>6 months, and English speaking. Exclusion criteria include: use of self INR-testing, home INR draws, dementia, or residing in a long-term care facility. A data collection form will be completed prior to INR measurement for a 6 month period. Information will be collected for subject demographics, warfarin adherence, INR stability, INR prediction, and prediction rationale. INR monitoring represents a significant burden with respect to cost and time. The results of this study may identify patient factors which could help individualize and decrease the frequency of INR monitoring in patients who receive maintenance warfarin therapy.

Interventions

None listed

Sponsors

University of Iowa
CollaboratorOTHER
Northeast Iowa Medical Education Foundation
Lead SponsorOTHER

Study design

Observational model
OTHER
Time perspective
PROSPECTIVE

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* Age ≥18 years * Warfarin use ≥60 days * INR goal of 2.0-3.0 or 2.5-3.5 * Expected warfarin use \>6 months * English speaking

Exclusion criteria

* Self INR-testing * Home INR draws * Dementia * Residence of a long-term care facility

Design outcomes

Primary

MeasureTime frameDescription
Assess factors which influence INR predictions6 monthsPatients will be asked to predict their INR value prior to having it tested. We will record patient's INR prediction and the value we obtain after testing INR.

Countries

United States

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026