Effects of Pharmaceutical Care for Elderly Patients Receiving Warfarin in Chaiya Hospital
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Abstract
Elderly patients receiving warfarin therapy are at an increased risk of suboptimal anticoagulation control and treatment-related complications. This study aimed to evaluate the effects of a pharmacist-led pharmaceutical care model on the effectiveness and safety of warfarin therapy among elderly patients at Chaiya Hospital. Methods: A retrospective pre-post analytical study was conducted using electronic medical records of elderly patients receiving continuous follow-up at the warfarin clinic between January 1, 2018 and June 30, 2024. A within-subject pre–post study was performed between a conventional pharmaceutical care model involving post-consultation alone and a developed model incorporating both pre- and post-consultation pharmacist interventions. Results: Sixty elderly patients met the inclusion criteria. Following the implementation of the developed pharmaceutical care model, the mean time in therapeutic range (TTR) increased significantly by 10.40% (95% CI: 3.58–17.21; p = 0.003). The incidence of a markedly subtherapeutic international normalized ratio (INR < 1.5) was significantly reduced (risk ratio = 0.53; 95% CI: 0.33–0.85; p = 0.009), accompanied by a significant reduction in minor bleeding events (risk ratio = 0.63; 95% CI: 0.42–0.95; p = 0.026). Thromboembolic complications showed a decreasing trend, whereas no significant differences were observed in a markedly supratherapeutic international normalized ratio (INR ≥ 5) or major bleeding events. Drug-related problems were identified in 11.45% of pharmaceutical care encounters, with medication nonadherence being the most common problem. Conclusion: The developed pharmacist-led pharmaceutical care model improved anticoagulation control and enhanced medication safety among elderly patients, thereby supporting the role of pharmacists in optimizing anticoagulation management in community hospital settings.
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