Considerations in using anticoagulant therapy in special patient populations

Katherine W. Phillips, Paul P Dobesh, Stuart T. Haines

Research output: Contribution to journalArticle

9 Citations (Scopus)

Abstract

Purpose. The role of genetic polymorphisms and genetic testing in guiding warfarin dosing is discussed, as are the selection and monitoring of anticoagulant therapy for obese patients, patients with severe renal impairment, and patients with heparin-induced thrombocytopenia (HIT); case studies are used to illustrate each topic. Summary. Genetic polymorphisms influence metabolism of and sensitivity to warfarin. People with certain ethnic backgrounds have a greater likelihood of having genetic polymorphisms that reduce warfarin dosing requirements and increase the risk of bleeding. Genetic testing has the potential to improve patient safety; however, its cost is high, and genetic polymorphisms account for only part of interindividual variation in dosing requirements. For obese patients, dose capping of low molecular weight heparin is not warranted, and twice-daily enoxaparin is preferred over once-daily dosing. Anti-Xa monitoring is perhaps not necessary for patients weighing less than 190 kg (418 lb), but it may be useful to adjust dosing in heavier patients. In patients with severe renal impairment, bleeding during anti-coagulant therapy may be attributed to the uremic state, excessive doses, or both. Dosage reduction and anti-Xa monitoring are recommended for patients with severe renal impairment. Treatment of patients with HIT should include discontinuation of heparin, temporary interruption of warfarin therapy, and initiation of a direct thrombin inhibitor. Conclusion. Safe and effective use of anticoagulant therapy may require consideration of genetics, obesity, renal impairment, or the potential for HIT; selecting anticoagulant therapy on the basis of these considerations can present a challenge.

Original languageEnglish (US)
JournalAmerican Journal of Health-System Pharmacy
Volume65
Issue number15 SUPPL. 7
DOIs
StatePublished - Aug 1 2008

Fingerprint

Anticoagulants
Genetic Polymorphisms
Population
Heparin
Warfarin
Thrombocytopenia
Kidney
Genetic Testing
Therapeutics
Hemorrhage
Enoxaparin
Coagulants
Antithrombins
Low Molecular Weight Heparin
Physiologic Monitoring
Patient Safety
Obesity
Costs and Cost Analysis

Keywords

  • Anticoagulants
  • Dosage
  • Genetics
  • Hemorrhage
  • Heparin
  • Kidney failure
  • Obesity
  • Tests
  • Thrombocytopenia
  • Toxicity
  • Warfarin

ASJC Scopus subject areas

  • Pharmacology
  • Health Policy

Cite this

Considerations in using anticoagulant therapy in special patient populations. / Phillips, Katherine W.; Dobesh, Paul P; Haines, Stuart T.

In: American Journal of Health-System Pharmacy, Vol. 65, No. 15 SUPPL. 7, 01.08.2008.

Research output: Contribution to journalArticle

@article{0b214fa6567e4f2db2c60906174c8ea7,
title = "Considerations in using anticoagulant therapy in special patient populations",
abstract = "Purpose. The role of genetic polymorphisms and genetic testing in guiding warfarin dosing is discussed, as are the selection and monitoring of anticoagulant therapy for obese patients, patients with severe renal impairment, and patients with heparin-induced thrombocytopenia (HIT); case studies are used to illustrate each topic. Summary. Genetic polymorphisms influence metabolism of and sensitivity to warfarin. People with certain ethnic backgrounds have a greater likelihood of having genetic polymorphisms that reduce warfarin dosing requirements and increase the risk of bleeding. Genetic testing has the potential to improve patient safety; however, its cost is high, and genetic polymorphisms account for only part of interindividual variation in dosing requirements. For obese patients, dose capping of low molecular weight heparin is not warranted, and twice-daily enoxaparin is preferred over once-daily dosing. Anti-Xa monitoring is perhaps not necessary for patients weighing less than 190 kg (418 lb), but it may be useful to adjust dosing in heavier patients. In patients with severe renal impairment, bleeding during anti-coagulant therapy may be attributed to the uremic state, excessive doses, or both. Dosage reduction and anti-Xa monitoring are recommended for patients with severe renal impairment. Treatment of patients with HIT should include discontinuation of heparin, temporary interruption of warfarin therapy, and initiation of a direct thrombin inhibitor. Conclusion. Safe and effective use of anticoagulant therapy may require consideration of genetics, obesity, renal impairment, or the potential for HIT; selecting anticoagulant therapy on the basis of these considerations can present a challenge.",
keywords = "Anticoagulants, Dosage, Genetics, Hemorrhage, Heparin, Kidney failure, Obesity, Tests, Thrombocytopenia, Toxicity, Warfarin",
author = "Phillips, {Katherine W.} and Dobesh, {Paul P} and Haines, {Stuart T.}",
year = "2008",
month = "8",
day = "1",
doi = "10.2146/ajhp080241",
language = "English (US)",
volume = "65",
journal = "American Journal of Health-System Pharmacy",
issn = "1079-2082",
publisher = "American Society of Health-Systems Pharmacy",
number = "15 SUPPL. 7",

}

TY - JOUR

T1 - Considerations in using anticoagulant therapy in special patient populations

AU - Phillips, Katherine W.

AU - Dobesh, Paul P

AU - Haines, Stuart T.

PY - 2008/8/1

Y1 - 2008/8/1

N2 - Purpose. The role of genetic polymorphisms and genetic testing in guiding warfarin dosing is discussed, as are the selection and monitoring of anticoagulant therapy for obese patients, patients with severe renal impairment, and patients with heparin-induced thrombocytopenia (HIT); case studies are used to illustrate each topic. Summary. Genetic polymorphisms influence metabolism of and sensitivity to warfarin. People with certain ethnic backgrounds have a greater likelihood of having genetic polymorphisms that reduce warfarin dosing requirements and increase the risk of bleeding. Genetic testing has the potential to improve patient safety; however, its cost is high, and genetic polymorphisms account for only part of interindividual variation in dosing requirements. For obese patients, dose capping of low molecular weight heparin is not warranted, and twice-daily enoxaparin is preferred over once-daily dosing. Anti-Xa monitoring is perhaps not necessary for patients weighing less than 190 kg (418 lb), but it may be useful to adjust dosing in heavier patients. In patients with severe renal impairment, bleeding during anti-coagulant therapy may be attributed to the uremic state, excessive doses, or both. Dosage reduction and anti-Xa monitoring are recommended for patients with severe renal impairment. Treatment of patients with HIT should include discontinuation of heparin, temporary interruption of warfarin therapy, and initiation of a direct thrombin inhibitor. Conclusion. Safe and effective use of anticoagulant therapy may require consideration of genetics, obesity, renal impairment, or the potential for HIT; selecting anticoagulant therapy on the basis of these considerations can present a challenge.

AB - Purpose. The role of genetic polymorphisms and genetic testing in guiding warfarin dosing is discussed, as are the selection and monitoring of anticoagulant therapy for obese patients, patients with severe renal impairment, and patients with heparin-induced thrombocytopenia (HIT); case studies are used to illustrate each topic. Summary. Genetic polymorphisms influence metabolism of and sensitivity to warfarin. People with certain ethnic backgrounds have a greater likelihood of having genetic polymorphisms that reduce warfarin dosing requirements and increase the risk of bleeding. Genetic testing has the potential to improve patient safety; however, its cost is high, and genetic polymorphisms account for only part of interindividual variation in dosing requirements. For obese patients, dose capping of low molecular weight heparin is not warranted, and twice-daily enoxaparin is preferred over once-daily dosing. Anti-Xa monitoring is perhaps not necessary for patients weighing less than 190 kg (418 lb), but it may be useful to adjust dosing in heavier patients. In patients with severe renal impairment, bleeding during anti-coagulant therapy may be attributed to the uremic state, excessive doses, or both. Dosage reduction and anti-Xa monitoring are recommended for patients with severe renal impairment. Treatment of patients with HIT should include discontinuation of heparin, temporary interruption of warfarin therapy, and initiation of a direct thrombin inhibitor. Conclusion. Safe and effective use of anticoagulant therapy may require consideration of genetics, obesity, renal impairment, or the potential for HIT; selecting anticoagulant therapy on the basis of these considerations can present a challenge.

KW - Anticoagulants

KW - Dosage

KW - Genetics

KW - Hemorrhage

KW - Heparin

KW - Kidney failure

KW - Obesity

KW - Tests

KW - Thrombocytopenia

KW - Toxicity

KW - Warfarin

UR - http://www.scopus.com/inward/record.url?scp=49649099069&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=49649099069&partnerID=8YFLogxK

U2 - 10.2146/ajhp080241

DO - 10.2146/ajhp080241

M3 - Article

VL - 65

JO - American Journal of Health-System Pharmacy

JF - American Journal of Health-System Pharmacy

SN - 1079-2082

IS - 15 SUPPL. 7

ER -