Patient Time Requirements for Anticoagulation Therapy with Warfarin

Background. Most patients receiving warfarin are managed in outpatient office settings or anticoagulation clinics that require frequent visits for monitoring. Objective. To measure the amount and value of time required of patients for chronic anticoagulation therapy with warfarin. Design/Participants. Prospective observation of a cohort of adult patients treated at a university-based anticoagulation program. Measurements. Participants completed a questionnaire and a prospective diary of the time required for 1 visit to the anticoagulation clinic, including travel, waiting, and the clinic visit. The authors reviewed subjects' medical records to obtain additional information, including the frequency of visits to the anticoagulation clinic. They used the human capital method to estimate the value of time. Results. Eighty-five subjects completed the study. The mean (median) total time per visit was 147 minutes (123). Subjects averaged 15 visits per year (14) and spent 39.0 hours (29.3) per year on their visits. Other anticoagulation-related activities, such as communication with providers, pharmacy trips, and extra time preparing food, added an average of 52.7 hours (19.0) per year. The mean annual value of patient time spent traveling, waiting, and attending anticoagulation visits was $707 (median $591). The mean annual value when also including other anticoagulation-related activities was $1799 (median $1132). Conclusions. The time required of patients for anticoagulation visits was considerable, averaging approximately 2.5 hours per visit and almost 40 hours per year. Methods for reducing patient time requirements, such as home-based testing, could reduce costs for patients, employers, and companions.