The North American Experience with Patient Self-Testing of the INR

ABSTRACT

The increased utilization of anticoagulant therapy has led to a spectrum of advances in management, including the use of International Normalized Ratio (INR) reporting, the development of anticoagulation clinics, the development of portable point-of-care INR devices, and the development of innovative testing modalities such as patient self-testing (PST). PST of the INR provides improved access to testing and a practical method to achieve high-frequency testing, typically on a once-a-week schedule. Implementation of self-testing has been widely adopted in Germany but has been accepted much more slowly in North America. The lack of effective reimbursement has been the greatest barrier to more widespread use of PST, but this is confounded by the lack of large-scale clinical trials, INR issues, and the lack of physician awareness and advocacy. Recent decisions by insurance authorities to provide limited reimbursement are providing some optimism for more widespread utilization of PST of the INR in the near future.

KEYWORDS

Warfarin - anticoagulation management - cost-effectiveness - point-of-care testing - prothrombin time

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