Age-related changes in vascular and haemostatic systems, which include platelets, coagulation and fibrinolytic factors, give rise to an increased thrombotic tendency in the elderly. Despite this risk, prophylaxis is often suboptimal in this age group and includes both substantial underuse (up to 35%) and overuse (up to 50%). Risk assessment models can helf to improve the prophylaxis in this age group. Current options for pharmacological prophylaxis include unfractionated heparin (UFH) and low-molecular-weight heparin (LMWH), warfarin (a vitamin K antagonist), and fondaparinux sodium.

Appropriate anticoagulation of at-risk patients offers a means of reducing the significant VTE burden in this population, but concerns have been raised over the use of anticoagulants in a patient group in whom multiple risk factors are common. Bleeding in the elderly can be exacerbated by reduced renal clearance and hypersensitivity to oral anticoagulants that may lead to over-anticoagulation, but this risk is often overemphasised,

American College of Chest Physicians recommendations for venous thromboembolism (VTE) prophylaxis in elderly patients and treatment of VTE

Levels of recomendatons:

1A = strong recommendation, can apply to most patients in most circumstances without reservation;

1B = strong recommendation, likely to apply to most patients;

1C+ = strong recommendation, can apply to most patients in most circumstances;

2A = intermediate-strength recommendation, best actions may differ depending on circumstances or patients’societal values;

2B = weak recommendation, alternative approaches likely to be better for some patients under some circumstances;

2C = very weak recommendation, other alternatives may be equally reasonable;

General recomendations:

1A: Aspirin alone is not recomendad in any patient group

1C: Renal impairment should be considered when deciding on  doses of LMWHs, fondaparinux sodium, direct thrombin inhibitors, particularly in elderly patients

In patients with a high risk of bleeding mechanical methods should be used instead of pharmacologial prophylaxis, until the bleeding risk decreases

General Surgery:

1A:Of higher risk are patients alter non-major surgery, aged >60 years; they should receive LMWH >3400U daily or LDUH 5000U tid; patients aged >60 years fall at least in the higher-risk category

1C: In high risk patients (major surgery, age >60 years) LMWH >3400U daily or LDUH 5000U tid should be used, combined with mechanical methods.

2A: Post-hospital discharge LMWH is recomendad in high risk surgery, including major cancer surgery

Orthopaedic surgery

1A: For elective hip or knee replacement prophylaxis should be made with LMWH high-risk dose or fondaparinux sodium 2.5 mg/kg or VKA with INR target 2.5 (range

2–3). Recomendations are against LDUH or venous foot pumps alone

For hip fracture surgery prophylaxis should be made with Fondaparinux 2.5 mg/kg (1A),

LMWH high-risk dose (1C+) orVKA with INR target 2.5 (range 2–3) (2B) or LDUH (1B).

If surgery is likely to be delayed, LMWH or LDUH should be initiated between hospital admissions and surgery (1C+)

Duration of prophylaxis should be at least 10 days (THA, TKA, hip fracture surgery) (1A); it should be extended up to 28–35 days alter THA and hip fracture surgery

Medical problems

Patients admitted to hospital with congestive heart failure or severe respiratory disease, or advanced age who are confined to bed and have one or more risk factors should receive prophylaxis with LMWH or LDUH (1A)

General recomendations:  Long term Warfarin with INR target 2.5 (range 2–3) (1A)

Cancer patients should receive prophylaxis with LMWH (3–6 months) (1A)

Patients with severe renal insufficiency should receive prophylaxis with LDUH (IV) rather than LMWH 2C

For deep vein trombosis short term low-molecular-weight heparin (sc) or low-dose unfractionated heparin (iv) are recomendad, combined with vitamin K antagonist (5 days), until INR is stable and >2 (1A)

For pulmonary embolism treatment consists of short term LMWH (sc) or LDUH (iv), combined with VKA (5 days), until INR is stable and >2 (1A)

In acute non-massive PE LMWH rather than UFH should be used (1A)

DEEP VEIN TROMBOSIS = deep vein trombosis

INR = International Normalized Ratio

IV = intravenous

LDUH = low-dose unfractionated heparin

LMWH = low-molecular-weight heparin

PE = pulmonary embolism

SC = subcutaneous; THA = total hip arthroplasty; tid = three times daily; TKA = total knee arthroplasty; UFH =

unfractionated heparin; VKA = vitamin K antagonist.

New anticoagulants like fondaparinux sodium may be of benefit in the aged patient, but clinical experience of this drug in the elderly are limited

References: Spyropoulos AC, Merli G: Management of Venous Thromboembolism in the Elderly Drugs Aging 2006; 23 (8): 651-671