Management of Chinese patients on warfarin therapy in two models of anticoagulation service - a prospective randomized trial

Abstract

Aim: To compare the treatment outcomes of a clinical pharmacist-managed anticoagulation service with physician-managed service in Chinese patients.

Methods: A prospective, randomized clinical trial was conducted at the anticoagulation clinic of a teaching hospital in Hong Kong. Patients aged > or = 18 years who would required warfarin therapy for at least 3 months were recruited. Patients were randomized to the pharmacist-managed or physician-managed group. Primary clinical outcome was assessed by the percentage of patient time spent within the target international normalized ratio (INR) range. The incidence of major thromboembolic events (TEs) and major bleeding was assessed as secondary clinical outcomes. The cost per patient per month (cPPPM) was calculated and patient satisfaction was assessed by patient satisfaction questionnaire (PSQ)-18.

Results: One hundred and forty-one patients were recruited at the anticoagulation clinic and 137 patients completed the study. Patients in the pharmacist-managed group (n = 68) were in the target INR 64% of patient time vs. 59% in the physician-managed group (n = 69) (P < 0.001). There was no significant difference in incidence of major TEs or bleeding. The cPPPM in the pharmacist-managed group (76 +/- 95 US dollar) (43 +/- 53 British pound) was lower than in the physician-managed group (98 +/- 158 US dollar) (55 +/- 89 British pound) (P < 0.001). The PSQ-18 score of the pharmacist-managed group (3.8 +/- 0.2) was higher than that of the physician-managed group (3.6 +/- 0.3) (P < 0.001).

Conclusion: The pharmacist-managed anticoagulation service was more effective and less costly than the physician-managed service in achieving target anticoagulation control for Chinese patients on warfarin therapy.

Figure 1

Flow of patients through the trial

Figure 2

Distribution of patient-years among the international normalized ratio (INR) categories in the low-intensity group (target INR =2–3, extended target INR =1.8–3.2). Pharmacist group (), Physician group ()

Figure 3

Distribution of patient-years among the international normalized ratio (INR) categories in the high-intensity group (target INR =2.5–3.5, extended target INR =2.3–3.7). Pharmacist group (), Physician group ()