Mortality rates and risk factors for asymptomatic deep vein thrombosis in medical patients

Paul T. Vaitkus; Alain Leizorovicz; Alexander T. Cohen; Alexander G. G. Turpie; Carl-Gustav Olsson; Samuel Z. Goldhaber; for the PREVENT Medical Thromboprophylaxis Study Group

doi:10.1160/TH04-05-0323

Thrombosis and Haemostasis, Table of Contents

Thromb Haemost 2005; 93(01): 76-79
DOI: 10.1160/TH04-05-0323

Blood Coagulation, Fibrinolysis and Cellular Haemostasis

Schattauer GmbH

Mortality rates and risk factors for asymptomatic deep vein thrombosis in medical patients

Paul T. Vaitkus

¹Cardiology Division, College of Medicine, University of Illinois at Chicago, Chicago, Illinois, USA and Clinical Research and Development, Pharmacia, Skokie, Illinois, USA

,

Alain Leizorovicz

²Unité de Pharmacologie Clinique, EA 643, Université Claude Bernard Lyon I, Lyon, France

,

Alexander T. Cohen

³Department of Academic Medicine, Guy’s, King’s and St Thomas’ School of Medicine, London, UK

,

Alexander G. G. Turpie

⁴Department of Medicine, Hamilton Health Sciences – General Hospital, Hamilton, Ontario, Canada

,

Carl-Gustav Olsson

⁵Verksamhetsområde Akutsjukvård, Universitetssjukhuset, Lund, Sweden Harvard Medical School, Boston, Massachusetts, USA

,

Samuel Z. Goldhaber

⁶Cardiovascular Division, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts, USA

,

for the PREVENT Medical Thromboprophylaxis Study Group

› Author Affiliations

Abstract

Summary

The clinical importance of asymptomatic proximal and distal deep vein thrombosis (DVT) remains uncertain and controversial. The aim of this retrospective,post-hoc analysis was to examine mortality and risk factors for development of proximal DVT in hospitalized patients with acute medical illness who were recruited into a randomized, prospective clinical trial of thromboprophylaxis with dalteparin (PREVENT).We analyzed 1738 patients who had not sustained a symptomatic venous thromboembolic event by Day 21 and who had a complete compression ultrasound of the proximal and distal leg veins on Day 21. We examined the 90-day mortality rates in patients with asymptomatic proximal DVT (Group I, N = 80), asymptomatic distal DVT (Group II, N = 118) or no DVT (Group III, N = 1540).The 90-day mortality rates were 13.75%, 3.39%, and 1.92% for Groups I–III, respectively. The difference in mortality between Group I and Group III was significant (hazard ratio 7.63, 95% CI = 3.8–15.3;p < 0.0001),whereas the difference between Groups II and III did not reach significance (hazard ratio 1.36, 95% CI = 0.41–4.45).The association of asymptomatic proximal DVT with increased mortality remained highly significant after adjusting for differences in baseline demographics and clinical variables. Risk factors significantly associated with the development of proximal DVT included advanced age (p = 0.0005), prior DVT (p = 0.001), and varicose veins (p = 0.04). In conclusion, the high mortality rate in patients with asymptomatic proximal DVT underscores its clinical relevance and supports targeting of asymptomatic proximal DVT as an appropriate endpoint in clinical trials of thromboprophylaxis.

Keywords

Venous embolism - deep vein thrombosis - proximal - prevention - dalteparin

Full Text

References

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