Clinical, economic, and humanistic impact of a multidisciplinary medication review with follow-up for anticoagulated patients treated with vitamin K antagonists in primary care: A cluster randomised controlled trial.

Background: Interdisciplinary collaboration between general practitioner, nurses and pharmacists can favour the control of patients treated with vitamin K antagonists (VKA), increasing their safety and effectiveness. The aim of the study was to evaluate the impact of pharmaceutical interventions on patients treated with VKA within the framework of a Pharmacotherapeutic Follow-up service on clinical, economic and humanistic outcomes.

Methods: Controlled and randomized study in patients from two health areas of Zaragoza in treatment with VKA with Time in Therapeutic Range (TTR) according to the Rosendaal method less than 70% in the last 6 months. Patients were recruited at the pharmacy and assigned to two groups: control and intervention. A Pharmacotherapeutic Follow-up Program was established for the intervention group for 6 months. The outcome variables were INR stability, pharmacological adherence, vitamin K intake, knowledge about the use of acenocoumarol, quality of life, satisfaction with treatment, associated costs and avoided costs. A descriptive analysis was performed, and the Students' T test or Mann-Whitney U test was used for the association between quantitative variables and Chi-square or Fisher's test for qualitative variables.

Results: A total of 123 patients were included, 65 in the intervention group (IG) and 58 in the control group (CG). A total of 108 interventions were conducted (1.7 interventions/patient) and the most common were those related to the proper taking of medications (41.0%). In IG, TTR (p = 0.019), adherence to treatment (p = 0.038) and knowledge about acenocoumarol (p = 0.031) improved, compared to CG. A higher proportion of patients in IG achieved a TTR>65% (p = 0.024). In addition, patients whose interventions were accepted by the physician (p = 0.027) and those who received vitamin K optimization interventions (p = 0.003) achieved TTR>65% in greater proportion.

Conclusions: Community pharmacist medication review, in collaboration with general practitioners improve knowledge and adherence of patients treated with oral anti-vitamin K agents and enhances the achievement of their therapeutic INR ranges. Investment needed to achieve this clinical impact is low and patient satisfaction is high.

Trial Registration: This study has been registered with Clinical Trials.gov dated 25/05/2017: NCT03154489.