The quality of pharmacist-led community warfarin management across 2 provinces in Canada: A cross-sectional observational study

Abstract

Background: Guidelines for anticoagulation management services recommend personnel be specially trained in warfarin management and suggest using tools such as decision-support software. To date, there have been no Canadian studies documenting the quality of warfarin management using a similar guideline recommended approach. Methods: A cross-sectional, retrospective observational study was conducted to measure the quality of pharmacist-led warfarin management using point-of-care international normalized ratio (INR) testing and decision-support software in various ambulatory settings in Canada. Settings included 4 family health teams in Ontario and 40 community pharmacies across Nova Scotia. Quality was measured using time in therapeutic range (TTR) and was reported in 3 manners: mean TTR, median TTR and time-weighted mean TTR. Results: The primary outcome included 963 patients. The combined mean and median TTR for the 2019 Ontario family health teams and Nova Scotia pharmacies was 74.2% and 77.3% (interquartile range 64%-87.9%), respectively. The time-weighted mean TTR was 76.3%. Discussion: To the best of our knowledge, the TTR achieved by this model of care is the highest reported in Canadian general practice. Since Thrombosis Canada defines good-quality warfarin management as a TTR of 60% or greater, and many studies have reported an association between higher TTR values and lower rates of thrombosis and hemorrhage, this model of care may have significant benefits for patients. Conclusion: This study demonstrates the high quality of anticoagulation management provided by specially trained pharmacists using point-of-care INR testing and decision-support software. These results support expanded access to this service for all Canadians. Can Pharm J (Ott) 2024;157:xx–xx.