Abstract 11835: Title: Quality and Efficacy of Patient Self-Management of Warfarin

Abstract

Objective: Patient self-management (PSM) is self-testing and altering the dose of their warfarin which allows for more frequent self-testing of warfarin levels, rapid results, timely dosage change, less dependency on the healthcare provider, and can be done anywhere. The objective of this study was to determine if PSM of warfarin is as safe and effective as healthcare provider dosing. Method: The setting for this study was a large cardiology practice that manages over 1000 patients on warfarin. Of these patients, 500 (50%) were using warfarin due to a valve replacement and 155 (16%) were engaged in self-testing. The final sample included 50 (32%) patients using self-testing who completed a 2-hour structured educational program on PSM of warfarin and practiced PSM for a 13-week period. Percentage of time the INR was maintained in therapeutic range, variance from the prescribed INR, and the adverse events of bleeding or thromboembolism were measured for 13 weeks pre-PSM and 13 weeks during PSM. Data were analyzed using t-test, correlation and Wilcoxson rank sum test. Results: There was no significant difference in pre-PSM time in therapeutic range compared with during PSM time in therapeutic range (p = .74). The mean INR variance from the prescribed INR range decreased significantly during PSM compared with pre-PSM, (p = .03), and when the INR did vary from the patient-specific prescribed range it tended to be in the high range but this did not reach significance (p = .67). These were desirable effects because this patient population is at high risk for embolic events. There was no significant increase in adverse events during PSM (p = .32). Conclusion: PSM of Warfarin was found to be as safe and effective as provider management. Moreover, PSM resulted in tighter control of INR variance compared with provider dosing. These results support the use of PSM of warfarin for eligible patients. Furthermore the model of PSM used in this study elicited patient engagement in behaviors that reduced the impact of their disease and decreased the burden of care on the healthcare provider.