The use of letter communication for patients enrolled in a pharmacist managed anticoagulation clinic

Abstract

It is unknown how letter communication vs. telephone communication compares in terms of affecting outcomes in patients followed in a busy anticoagulation clinic. This study was performed to determine if sending letters to communicate laboratory results and future appointments with patients enrolled in a pharmacy managed anticoagulation clinic is an effective alternative to telephone communication. A retrospective review of quality assurance data currently collected at our facility was performed. Data were analyzed 4 months before and 4 months after the implementation of the letter notification. Data on percent international normalized ratio (INR) in therapeutic range, missed laboratory draw frequency and major bleeding events were collected daily, compiled monthly and then compared between the telephone and letter groups. There was no statistical difference in the percentage of INRs that were within goal range before and after letter initiation. There was a slight increase in the percentage of INR laboratory draws that were missed after the implementation of the letters (23% vs. 26%, P = 0·002). There were more major bleeding events after letter initiation, but this did not reach statistical significance. Approximately 80% of the patients received letters as the method of communication in the letter group. The use of letters to notify warfarin patients with laboratory results is an effective method of communication without adversely affecting patient outcomes.