Use of an extended INR follow-up interval for Veteran patients in an anticoagulation clinic.
A prospective, single-arm study of 50 participants evaluated an extended INR follow-up interval to determine the implementation feasibility and safety of an extended interval in Veterans on a stable dose of warfarin. A protocol was designed to allow for a rigorous, yet pragmatic evaluation of a 12-week INR follow-up interval. Feasibility was determined by study enrollment, retention, and participant achievement rates for the extended INR interval. Safety was determined by bleeding and thromboembolism rates. Participants were monitored for 6 months. Despite the long-term stability of participants prior to enrollment, only 56% achieved a 12-week follow-up interval and only 34% of enrolled participants maintained a 12-week interval. Sixteen percent of participants were never eligible for an extension of their INR follow-up interval despite meeting initial enrollment criteria. There were two major bleeding events and one participant who experienced a thromboembolic event. Implementation of an extended interval of INR follow-up appears feasible as participant enrollment goals were met and pharmacists were able to follow the study protocol. However, a lower than expected proportion of participants were able to achieve and maintain an extended INR follow-up interval. Future evaluations are needed to confirm the safety of an extended INR interval.
University of Wisconsin-Madison School of Pharmacy, 777 Highland Ave., Madison, WI, 53705, USA. andrea.porter@wisc.edu.|William S. Middleton Memorial Veterans Hospital, 2500 Overlook Terrace (119), Madison, WI, 53705, USA. andrea.porter@wisc.edu.
Andrea L
AL
Porter
University of Wisconsin-Madison School of Pharmacy, 777 Highland Ave., Madison, WI, 53705, USA.|William S. Middleton Memorial Veterans Hospital, 2500 Overlook Terrace (119), Madison, WI, 53705, USA.
Amanda R
AR
Margolis
William S. Middleton Memorial Veterans Hospital, 2500 Overlook Terrace (119), Madison, WI, 53705, USA.|Texas Tech University Health Sciences Center, 4500 S. Lancaster Rd., Bldg. 7, Dallas, TX, 75216, USA.
Rebecca R
RR
Schoen
William S. Middleton Memorial Veterans Hospital, 2500 Overlook Terrace (119), Madison, WI, 53705, USA.
Carla E
CE
Staresinic
William S. Middleton Memorial Veterans Hospital, 2500 Overlook Terrace (119), Madison, WI, 53705, USA.
Cheryl A
CA
Ray
William S. Middleton Memorial Veterans Hospital, 2500 Overlook Terrace (119), Madison, WI, 53705, USA.|Division of Hematology, University of Wisconsin School of Medicine and Public Health, 750 Highland Ave., Madison, WI, 53726, USA.
Christopher D
CD
Fletcher
D000328:Adult; D000368:Aged; D000554:Ambulatory Care Facilities; D000925:Anticoagulants / Q000009:adverse effects / Q000627:therapeutic use*; D001071:Appointments and Schedules; D016903:Drug Monitoring / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D019934:International Normalized Ratio / Q000592:standards*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D013997:Time Factors; D016896:Treatment Outcome; D014728:Veterans; D014859:Warfarin / Q000009:adverse effects / Q000627:therapeutic use
D000925:Anticoagulants; D014859:Warfarin
Anticoagulation; International normalized ratio (INR); Interval; Management; Monitoring; Warfarin