Outcomes of pharmacist counseling on outpatients receiving warfarin at Samutprakarn Hospital

Abstract

This one group pre-test and post-test study was designed to assess the outcome of pharmacist counseling on outpatients receiving warfarin therapy by compare patients’ knowledge, compliance, International Normalized Ratio (INR), bleeding and thromboembolic events, and cost for hospitalization and ER visits between pre- and post- pharmacist counseling from January 2008 to January 2009. Samples were outpatients who received long-term warfarin therapy at Samutprakarn Hospital during the study period and have been followed up at warfarin clinic not less than 3 visits. Data were collected on 132 outpatients from an intervention day until three follow-up at warfarin clinic. Patients’ knowledge of warfarin therapy increased after receiving pharmacist counseling service and maintained until a third visit. Patients’ compliance to warfarin regimens was improved in the second visit. Percentage of patients whose INR within therapeutic range was increase after receiving pharmacist counseling (22.1% VS 73.5%). Percentage of patients whose INR lower and higher than therapeutic range were decreased after receiving pharmacist service (53.8% VS 14.1%, 24.1% VS 12.4%). Bleeding and thromboembolic events at post pharmacist counseling were reported lower than pre-pharmacist counseling (3.6% VS 1.7%, 2.2% VS 1.6%). A lower event of hospitalizations after counseling service (10 events VS 4 events) produced cost saving of 242,357.52 baht. From this study showed that pharmacist counseling could improved patients’ knowledge, compliance, anticoagulation control, reduced bleeding and thromboembolic events and annually saved cost in reduced ER visits and hospitalizations.