Warfarin for atrial fibrillation in community-based practise

Area of Science:

• Cardiology
• Pharmacology
• Public Health

Background:

• Previous anticoagulation studies for atrial fibrillation (AF) were primarily in academic settings, limiting generalizability.
• Real-world data on warfarin management in community practice for AF patients is crucial.

Purpose of the Study:

• To describe the management and outcomes of patients with AF treated with warfarin in community-based practices.
• To assess the variability in anticoagulation control and associated clinical events.

Main Methods:

• A cohort of 3396 patients from 101 community practices across 38 states were analyzed.
• Data collected included patient demographics, comorbidities, and International Normalized Ratio (INR) values.
• Key outcomes measured were time in therapeutic INR range (TTR), stroke incidence, and major hemorrhage rates.

Main Results:

• The mean TTR was 66.5%, with significant patient-level variation (37% >75% TTR, 34% <60% TTR).
• Yearly rates for major hemorrhage and stroke were 1.90 and 1.00 per 100 person-years, respectively.
• New warfarin users and patients with procedural interruptions had lower TTR, though interruptions' impact diminished after excluding peri-procedural values.

Conclusions:

• Anticoagulation control with warfarin for AF varies widely in community settings.
• While stroke and hemorrhage rates were low in this cohort, factors like new use, interruptions, and target INR affect TTR.
• The benefit of lower INR targets to reduce bleeding risk requires further investigation.