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A prospective study investigating the causes of warfarin under-utilization in Chinese patients

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Abstract

Background Warfarin is efficacious for ischemic stroke prevention in intermediate- to high-risk patients with atrial fibrillation; thus, warfarin is the recommended treatment according to evidence-based guidelines. Objective This prospective study evaluated the reasons for under-utilization of warfarin in Chinese patients with non-valvular atrial fibrillation (NVAF). Setting The People’s Hospital of Henan Province of Zhengzhou City, which is a 3900-bed tertiary-care teaching institution. Methods We extracted data from an existing patient database. Patients at risk for thromboembolism were categorized based on CHA2DS2-VASc [congestive heart failure, hypertension, age ≥75 (doubled), diabetes, prior stroke (doubled), vascular disease, age 65–74 years, and sex category (female)] scores. Main outcome measure The percent of warfarin utilization was estimated in recruited patients. Any demographic and clinical factors associated with warfarin under-utilization were identified using a logistic regression model. Results Among the patient sample (n = 612), 569 patients had a CHA2DS2-VASc score of ≥1. At presentation, warfarin under-utilization was estimated to be 27.1 %. Only 120 patients (25.1 %) considered to be at the highest risk were prescribed warfarin. Binary logistic regression analysis indicated that previous stroke, age ≥75 years, and anti-platelet therapy were associated with warfarin under-utilization. Conclusion Patients with CHA2DS2-VASc scores ≥1 who were admitted with NVAF were under prescribed warfarin, and 138 patients were not treated with either warfarin or other antithrombotic therapies. In conclusion, a more aggressive approach for stroke prevention in NVAF patients is required.

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Acknowledgments

The authors thank all patients, pharmacists, and physicians who contributed to the success of this work. We would also like to recognize Shijie Liang who performed statistical analysis. We thank the student interns who helped with data collection.

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Authors and Affiliations

  1. Department of Pharmacy, People’s Hospital of Henan Province, Zhengzhou, 450003, Henan, China

    Shujuan Zhao, Hongwei Zhao, Yuhua Qin, Haixia Cai, Boya Chen & Jingjing Cao

  2. Department of Cardiovascular Medicine, People’s Hospital of Henan Province, Zhengzhou, 450003, Henan, China

    Xianpei Wang & Chuanyu Gao

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  1. Shujuan Zhao
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  2. Hongwei Zhao
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  3. Xianpei Wang
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  4. Chuanyu Gao
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  5. Yuhua Qin
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  7. Boya Chen
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Correspondence to Yuhua Qin.

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Zhao, S., Zhao, H., Wang, X. et al. A prospective study investigating the causes of warfarin under-utilization in Chinese patients. Int J Clin Pharm 38, 1286–1293 (2016). https://doi.org/10.1007/s11096-016-0367-5

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  • DOI: https://doi.org/10.1007/s11096-016-0367-5

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