Evaluation of patients' knowledge on warfarin in outpatient anticoagulation clinics in a teaching hospital in Qatar

OBJECTIVE: To evaluate the extent and quality of the patient's education on warfarin and its possible impact on the international normalized ratio (INR).

METHODS: This is a cross-sectional study using a 20-item, self administered questionnaire of knowledge, offered to patients who were taking warfarin for at least 2 months and attending the medical or cardiology anticoagulation clinics in Hamad General Hospital, Hamad Medical Corporation, State of Qatar between August 2008 to November 2008.

RESULTS: A total of 140 patients completed the questionnaire, 116 patients (83%) reported that they received warfarin education and 61 patients (44%) had a controlled INR. Of the 79 patients with satisfactory knowledge (namely, overall score of at least 75%), 49 (62%) had a therapeutic INR compared with 12 (20%) having unsatisfactory knowledge (p<0.0001). The lowest scores were for participants' knowledge on the effects of a missing dose and its management (42%) and for warfarin drug interactions (36%).

CONCLUSION: An integrated and multidisciplinary education program may improve the patient's knowledge on warfarin as well as patient's compliance. This might lead to a better anticoagulation control, fewer clinic visits, and decrease in healthcare service load. Special attention should be addressed to geriatric patients and to those patients with low educational level and language barriers.