Treatment of Venous Thromboembolism in Older People

The incidence of venous thromboembolism increases markedly with age. Anticoagulation is effective in secondary prevention of venous thromboembolism but in older people, anticoagulation may be associated with increased risk of haemorrhage. Furthermore, given the high prevalence of renal impairment, there is risk of accumulation of renally cleared drugs (e.g. low molecular weight heparins, fondaparinux, some of the new anticoagulants). Older people tend to have more comorbidities and are on more medications which can potentially interact with anticoagulants. Older people are generally more sensitive to warfarin and require lower doses to maintain therapeutic anticoagulation. With the discovery of genetic polymorphisms that influence warfarin metabolism, dosing algorithms based on pharmacogenomics have been devised and are being evaluated to help improve the safety of anticoagulation.