Heparin and warfarin anticoagulation intensity as predictors of recurrence after deep vein thrombosis or pulmonary embolism: A population-based cohort study

John A. Heit, Brian D. Lahr, Tanya M. Petterson, Kent R. Bailey, Aneel A. Ashrani, L. Joseph Melton

Research output: Contribution to journalArticle

54 Scopus citations

Abstract

To test recommended anticoagulation measures as predictors of 180-day venous thromboembolism (VTE) recurrence, we identified all Olmsted County, MN residents with incident VTE over the 14-year period of 1984-1997, and followed eachcase (N ∇ 1166) forward in time for VTE recurrence. We tested the activated partial thromboplastin time (APTT), international normalized ratio (INR), and other measures of heparin and warfarin anticoagulation as predictors of VTE recurrence while controlling for baseline and time-dependent characteristics using Cox proportional hazards modeling. Overall, 1026 (88%) and 989 (85%) patients received heparin and warfarin, respectively, and 85 (8%) developed VTE recurrence. In multivariable analyses, increasing proportions of time on heparin with an APTT ≥ 0.2 anti-X a U/mL and on warfarin with an INR ≥ 2.0 were associated with significant reductions in VTE recurrence, while the hazard with active cancer was significantly increased. Time from VTE onset to heparin start, duration of overlapping heparin and warfarin, and inferior vena cava (IVC) filter placement were not independent predictors of recurrence. At a heparin dose ≥ 30 000 U/d, the median proportion of time with an APTT ≥ 0.2 anti-X aU/mL was 92%, suggesting that routine APTT monitoring and heparin dose adjustment may be unnecessary. In summary, lower-intensity heparin and standard-intensity warfarin anticoagulation are effective in preventing VTE recurrence.

Original languageEnglish (US)
Pages (from-to)4992-4999
Number of pages8
JournalBlood
Volume118
Issue number18
DOIs
StatePublished - Nov 3 2011

ASJC Scopus subject areas

  • Biochemistry
  • Immunology
  • Hematology
  • Cell Biology

Fingerprint Dive into the research topics of 'Heparin and warfarin anticoagulation intensity as predictors of recurrence after deep vein thrombosis or pulmonary embolism: A population-based cohort study'. Together they form a unique fingerprint.

  • Cite this