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Published on: October 12, 2012

INR deviations in hemodialyzed patients under low dose oral anticoagulant therapy

Athina Gompou1, Ioannis Griveas, Ilias Kyritsis

  • 1Nefroiatriki Renal Unit, Athens, Greece.

The International Journal of Artificial Organs
|November 28, 2009
PubMed

Insights

Elderly hemodialyzed patients on oral anticoagulation can achieve safe International Normalized Ratio (INR) levels. Low-dose anticoagulation therapy is effective and should not be automatically contraindicated in this group.

Area of Science:

  • Nephrology
  • Geriatrics
  • Pharmacology

Background:

  • Oral anticoagulation is crucial for preventing thromboembolic events in uremic hemodialyzed patients.
  • Managing anticoagulation in elderly, hemodialyzed patients presents unique challenges due to potential comorbidities and altered drug metabolism.

Purpose of the Study:

  • To evaluate the International Normalized Ratio (INR) control in elderly, uremic patients undergoing hemodialysis and treated with oral anticoagulation.
  • To assess the safety and efficacy of low-dose oral anticoagulation in this specific patient population.

Main Methods:

  • A retrospective study analyzing INR data from 11 elderly (70-85 years) uremic hemodialyzed patients on daily acenocoumarol.
  • INR measurements (n=129) were categorized into under-anticoagulation, target-anticoagulation (2-2.5), and over-anticoagulation.

Main Results:

  • 37.5% of INR measurements were within the target range (mean 2.20 +/- 0.14).
  • 30% were under-anticoagulated (mean 1.78 +/- 0.14) and 32.5% were over-anticoagulated (mean 3.14 +/- 0.64).
  • No thromboembolic or major bleeding events were reported during the study period.

Conclusions:

  • Adequate and safe INR levels are achievable in a high proportion of elderly, hemodialyzed uremic patients using low-dose oral anticoagulation.
  • Oral anticoagulation therapy should be considered a viable option for this patient group, not automatically contraindicated.

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