Korean Circ J.  2012 Feb;42(2):113-117. 10.4070/kcj.2012.42.2.113.

Trends in Oral Anticoagulation Therapy Among Korean Patients With Atrial Fibrillation: The KORean Atrial Fibrillation Investigation

• Shin HW
• Kim YN
• Bae HJ
• Lee HM
• Cho HO
• Cho YK
• Park HS
• Yoon HJ
• Kim H
• Nam CW
• Hur SH
• Kim KB
• Lee YS
• KORAF Investigator

• KMID: 1826383
• DOI: http://doi.org/10.4070/kcj.2012.42.2.113

Abstract

BACKGROUND AND OBJECTIVES
Anticoagulation with vitamin K antagonists (VKAs) such as warfarin provides effective stroke prophylaxis in patients with atrial fibrillation (AF). We conducted a large multicenter survey of Korean patients with AF to determine trends in VKA use.
SUBJECTS AND METHODS
Eligible patients were adults with AF that had been prescribed VKAs. Medical records from a total of 5616 patients {mean age 63.6+/-12.2 years, male 3150 (56.1%)} in 27 hospitals from Jan. 2001 to Oct. 2007 were reviewed.
RESULTS
The mean international normalized ratio (INR) was 2.04+/-0.64, and mean dosage of VKA was 3.66+/-1.50 mg. Individuals in their sixties (1852 patients) accounted for about one third of patients studied. As patients grew older, INR increased and VKA dosage decreased. The dosage of VKA in male patients was larger than that in females for all ages. A total of 2146 (42.4%) patients had an INR of 2-3, and less than 40% patients in their sixties had an INR within optimal range. The dosage of oral anticoagulant for optimal INR level was 3.71 mg.
CONCLUSION
In this study, less than half of the Korean patients with AF on VKA reached the therapeutic range of INR. Mean dosage of VKA was 3.66+/-1.50 mg, and the dosage of oral anticoagulant for optimal INR level was 3.71 mg, which decreased with age.

Keyword

Atrial fibrillation; International Normalized Ratio; Anticoagulants

MeSH Terms

Adult
Anticoagulants
Atrial Fibrillation
Female
Humans
International Normalized Ratio
Male
Medical Records
Stroke
Vitamin K
Warfarin
Anticoagulants
Vitamin K
Warfarin

Figure

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  Fig. 1 Average INR level according to age group. The mean INR level of older patients was slightly higher than that of younger patients. INR: international normalized ratio.

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  Fig. 2 Average dosage of oral anticoagulant according to age group. There was significant difference in dosage of oral anticoagulant according to age group. OAC: oral anticoagulant.

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  Fig. 3 Average dosage of oral anticoagulant according to INR group. The dosage of oral anticoagulant in the lower INR group was higher than that in higher INR group. INR: international normalized ratio.

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  Fig. 4 Proportion of INR level in patient with AF who taken oral anticoagulants. The proportion of individuals achieving an optimal INR level (2-3) was only 42.4%. INR: international normalized ratio, AF: atrial fibrillation.

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  Fig. 5 Proportion of optimal INR level (2-3) according to age group. The proportion of individuals achieving optimal INR level was higher among younger women and older men. INR: international normalized ratio.

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  Fig. 6 Dosage of oral anticoagulant (OAC) for optimal international normalized ratio level (2-3) according to age group. The dosage of oral anticoagulant in men and women gradually decreased with increasing age.

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