Economic evaluation of a randomized controlled trial of pharmacist-supervized patient self-testing of warfarin therapy

What is known and objective The increase in numbers of patients requiring oral anti-coagulation testing in outpatient clinics has focused attention on alternative flexible systems of anti-coagulation management. One option is pharmacist led patient self-testing (PST) of international normalised ratio (INR) levels. PST has demonstrated improvements in anti-coagulation control, but its cost-effectiveness is inconclusive. This study reports the first cost-effectiveness evaluation of a randomized controlled trial of an automated direct-to-patient expert system, enabling remote and effective management of patients on oral anti-coagulation therapy. Methods We conducted an economic evaluation alongside a randomised controlled trial investigating a pharmacist led PST method. The primary outcome was to determine the cost effectiveness of PST in comparison with usual care (management in a hospital based anti-coagulation clinic). Long term anti-coagulation patients were recruited to a 6 month cross over study between PST and routine care in an anti-coagulation clinic. Economic evaluation was from the healthcare payer perspective. Results and discussion On a per patient basis over a 6 month period, PST resulted in an incremental cost of €59·08 in comparison with routine care. Patients achieved a significantly higher time in therapeutic range (TTR) during the PST arm in comparison with routine care, (72 ± 19·7% vs. 59 ± 13·5%). Overall cost of managing a patient through pharmacist supervised PST for a 6 month period is €226·45. Additional analysis of strategies from a societal perspective indicated that PST was the dominant strategy. What is new and conclusion Pharmacist led patient self-testing is a viable method of management. It provides significant increases in anti-coagulation control for a minimal increase in cost. An economic evaluation of a novel method of pharmacist supervising anticoagulation management. Intervention resulted in a a significant increase in quality of anticoagulation control for a minimal increase in cost.