Advertisement

International Journal of Hematology

, Volume 78, Issue 1, pp 84–86 | Cite as

Racial background is a determinant factor in the maintenance dosage of Warfarin

  • Gin Gin Gan
  • Alan Teh
  • Kim Yen Goh
  • Heng Thay Chong
  • Kang Wah Pang
Article

Abstract

Warfarin is a drug commonly used in the prevention of thromboembolic events. There have been reports suggesting that racial background may influence warfarin dose requirements. Malaysia is a multiracial country in which there are 3 major races, Malay, Chinese, and Indian.We examined 100 patients from our hospital on stable maintenance doses of warfarin, with international normalized ratio (INR) of 2.0 to 3.5.We found that the mean warfarin dose for Indian patients (n = 19) was 6.9 mg, for Chinese patients (n = 55) was 3.6 mg, and for Malay patients (n = 26) was 3.2 mg.The results showed that the Indian patients required a statistically significantly higher warfarin dose than did patients of the other 2 races (P >.0005). Age was also found to affect the daily warfarin maintenance dose.

Key words

Racial background Warfarin 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    Yu HM, Chan TYK, Critchley JAJH, Woo KS. Factors determining the maintenance dose of warfarin in Chinese patients.Q J Med. 1996;89:127–135.Google Scholar
  2. 2.
    Blann A, Hewitt J, Siddiqui F, Bareford D. Racial background is a determinant of average warfarin dose required to maintain INR between 2.0 and 3.0.Br J Haematology. 1999;107:207–209.CrossRefGoogle Scholar
  3. 3.
    James AH, Britt RP, Raskino CL, Thompson SG. Factors affecting the maintenance dose of warfarin.J Clin Path. 1992;45: 704–706.CrossRefPubMedGoogle Scholar
  4. 4.
    Aithal GP, Day CP, Kersteven PJ, et al. Association of polymorphisms in the cytochrome P450 CYP2C9 with warfarin dose requirement and risk of bleeding complications.Lancet. 1999;353: 717–719.CrossRefPubMedGoogle Scholar
  5. 5.
    Takayashi H, Hirotoshi E. Pharmacogenetics of warfarin elimination and its clinical implications.Clin Pharmacokinet. 2001;40: 587–603.CrossRefGoogle Scholar
  6. 6.
    Goldstein JA. Clinical relevance of genetic polymorphisms in the human CYP2C subfamily.Br J Clin Pharmacol. 2001;52:349–355.CrossRefPubMedGoogle Scholar
  7. 7.
    Zhou HH, Adedoyin A, Wilkinsons GR. Differences in plasma binding of drugs between Caucasians and Chinese subjects.Clin Pharmacol Ther. 1990;48:10–17.PubMedGoogle Scholar
  8. 8.
    Gladman JRF, Dolan G. Effect of age upon the induction and maintenance of anticoagulation with warfarin.Postgrad Med J. 1995;71:153–155.CrossRefPubMedGoogle Scholar

Copyright information

© The Japanese Society of Hematology 2003

Authors and Affiliations

  • Gin Gin Gan
    • 1
  • Alan Teh
    • 1
  • Kim Yen Goh
    • 1
  • Heng Thay Chong
    • 1
  • Kang Wah Pang
    • 2
  1. 1.Department of Medicine, Faculty of MedicineUniversity MalayaKuala LumpurMalaysia
  2. 2.Primary Industry Statistics Division, Department of StatisticsMalaysia

Personalised recommendations