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Overview

Venous thromboembolism (VTE) consists of deep vein thrombosis (DVT), pulmonary embolism (PE), or both. The risk factors for VTE are a constellation of predisposing conditions which stem from the three principles of Virchow's triad: stasis of the blood flow, damage to the vascular endothelial cells, and hypercoagulability. The risk factors for VTE can be categorized as temporary, modifiable and non-modifiable. Venous thrombosis also shares risk factors with cardiac thrombosis, such as obesity, hypertension and smoking.

Risk Factors

Shown below is a list of predisposing factors to VTE.[1][2] The risk factors are classified as strong, moderate and weak depending on how strongly they predispose for a VTE.

Strong risk factors Moderate risk factors Weak risk factors
Bone fracture (hip or leg)

Hip replacement surgery
❑ Knee replacement surgery
Major general surgery
Significant trauma
Spinal cord injury

❑ Athroscopic knee surgery

Central venous lines
Chemotherapy
Chronic heart failure
Respiratory failure
Hormone replacement therapy
Cancer
Oral contraceptive pills
Stroke
Pregnancy
Postpartum
❑ Prior history of VTE
Thrombophilia

❑ Bed rest for more than 3 days

❑ Prolonged car or air travel
❑ Advanced age
Laparoscopic surgery
❑ Prepartum
Obesity
Varicose veins

The risk factors of VTE can be further classified into modifiable, non-modifiable and temporary:

Modifiable Risk Factors

Modifiable risk factors are reversible based upon lifestyle/behavior modification.

  • Obesity: Obesity is defined as a body-mass index (BMI) above 30 kg/m2.[3] [4] [5]
  • Prolonged travel (Travel by air increases the risk to the same extent as travel by bus, train or car, suggesting that the increased risk of air travel is due primarily to prolonged immobility)[7]
  • Hyperhomocysteinemia[8]

Non-Modifiable Risk Factors

Temporary Risk Factors

  • Injury to a deep vein from surgery, a fracture, or other trauma, especially a paralytic spinal cord injury [1]
  • Prolonged Immobilization causes stasis in the deep veins which may occur after surgery, with prolonged bedrest, or prolonged seating during travel.
  • Pregnancy and the peri-partum period
  • Active cancer
  • Central venous catheter

Thrombophilia

Genetic Thrombophilia

Acquired Thrombophilia

References

  1. 1.0 1.1 Anderson FA, Spencer FA (2003). "Risk factors for venous thromboembolism". Circulation. 107 (23 Suppl 1): I9–16. doi:10.1161/01.CIR.0000078469.07362.E6. PMID 12814980.
  2. Torbicki A, Perrier A, Konstantinides S, Agnelli G, Galiè N, Pruszczyk P; et al. (2008). "Guidelines on the diagnosis and management of acute pulmonary embolism: the Task Force for the Diagnosis and Management of Acute Pulmonary Embolism of the European Society of Cardiology (ESC)". Eur Heart J. 29 (18): 2276–315. doi:10.1093/eurheartj/ehn310. PMID 18757870.
  3. 3.0 3.1 Holst AG, Jensen G, Prescott E (2010). "Risk factors for venous thromboembolism: results from the Copenhagen City Heart Study". Circulation. 121 (17): 1896–903. doi:10.1161/CIRCULATIONAHA.109.921460. PMID 20404252.
  4. Vayá A, Martínez-Triguero ML, España F, Todolí JA, Bonet E, Corella D (2011). "The metabolic syndrome and its individual components: its association with venous thromboembolism in a Mediterranean population". Metab Syndr Relat Disord. 9 (3): 197–201. doi:10.1089/met.2010.0117. PMID 21352080.
  5. Eichinger S, Hron G, Bialonczyk C, Hirschl M, Minar E, Wagner O; et al. (2008). "Overweight, obesity, and the risk of recurrent venous thromboembolism". Arch Intern Med. 168 (15): 1678–83. doi:10.1001/archinte.168.15.1678. PMID 18695082.
  6. Pomp ER, Rosendaal FR, Doggen CJ (2008). "Smoking increases the risk of venous thrombosis and acts synergistically with oral contraceptive use". Am J Hematol. 83 (2): 97–102. doi:10.1002/ajh.21059. PMID 17726684.
  7. http://wwwnc.cdc.gov/travel/yellowbook/2012/chapter-2-the-pre-travel-consultation/deep-vein-thrombosis-and-pulmonary-embolism.htm
  8. den Heijer M, Koster T, Blom HJ, Bos GM, Briet E, Reitsma PH; et al. (1996). "Hyperhomocysteinemia as a risk factor for deep-vein thrombosis". N Engl J Med. 334 (12): 759–62. doi:10.1056/NEJM199603213341203. PMID 8592549.