[New oral anticoagulants for the prevention of stroke. Open questions in geriatric patients].

New oral anticoagulants for the prevention of stroke in patients with nonvalvular atrial fibrillation have been available for a few months, among them the reversible direct thrombin inhibitor dabigatran and the factor Xa antagonist rivaroxaban. These drugs are considered by some as a superior alternative to vitamin K antagonists. The lack of necessity for regular monitoring is advertised as a major advantage. Although atrial fibrillation is a disease with increasing prevalence with higher age, the suitability of the new drugs has not been extensively studied in multimorbid geriatric patients. Since dabigatran is contraindicated in patients with renal insufficiency, only the lower of the two approved dosages can usually be prescribed in elderly patients. For the lower dosage, however, no superiority in prevention of stroke has been documented but merely a reduction in major bleeding rates, although at a high number needed to treat. The requirement for a twice-daily dosage regimen, the lack of an anticoagulation monitoring option, the relatively short duration of action and the lack of an antidote may even prove to be crucial disadvantages in clinical practice in comparison to vitamin K antagonists. Until more data are available, the new oral anticoagulants should be prescribed with caution in geriatric patients.