[Assessing post-hospitalization therapeutic ranges in elderly patients treated for atrial fibrillation with vitamin k antagonists]

Abstract

Background: In France, anticoagulants are among the most recommended treatments for serious accidents, particularly among the elderly.

Objectives: The purpose of this study was to evaluate the impact of practical and validated tools designed to reduce the negative effects of vitamin K antagonist (VKA) treatments by assessing patients before and after the tools were implemented.

Methods: An exhaustive before and after multi-centric cohort study was performed in the Agen territory. The follow-up period corresponded to the six-month period post-hospitalization. The principal criterion was the time in the therapeutic range (TTR) at values of 2 to 3 according to the Rosendaal method.

Results: The overall time spent in the follow-up period before and after the implementation of the tools in 65- and 74-year-old patients was 58% and 64%, respectively (P=0.584). After the treatments, the TTR in the 85- to 90-year-old patients was 71.1%. An increase was observed in the number of subjects with a TTR≥70% after the implementation of the tools according to age, particularly in the 85- to 90-year-old patients (8 vs. 41; [P=0.01]). Prescription help software revealed a tendency of improvement in TTR values from 61% to 68% (P=0.472). In addition, longer therapeutic periods corresponded to longer patient lifespans (r=0.86).

Conclusion: This study demonstrates the feasibility and advantages of implementing tools to improve the efficacy of VKA treatment in primary care, particularly for patients from 85 to 90 years old. The results should promote the implementation of this type of treatment method at the national level.

Keywords: Ambulatory Care; Antivitamine-K; Atrial Fibrillation; Computerized Dosing System; Elderly; Fibrillation Atriale; Logiciel d’aide à la prescription; Suivi ambulatoire; Sujets âgés; Vitamin K Antagonist.