Adverse event rates associated with oral anticoagulant treatment early versus later after hospital discharge in older adults: a retrospective population-based cohort study

Abstract

O ral anticoagulants, including warfarin and the direct-acting anticoagulants, are highly effective for the prevention of stroke and systemic embolism in patients with atrial fibrillation, as well as for the treatment and prevention of venous thromboembolism. [1][2][3][4][5] Both conditions increase in prevalence with increasing age. 6,7 More than 7 million prescriptions in Canada and more than 37 million prescriptions in the United States are filled annually for oral anticoagulant treatment. 8,9 As thromboembolic events increase with increasing age, the absolute risk reduction in events obtained with oral anticoagulant treatment is greater for older adults than for younger people. [10][11][12] Despite their benefit, oral anticoagulants are considered high-risk medications because of the risk of substantial harm -mainly bleeding or thromboembolic events, and death -if treatment is not well managed. 13 Oral anticoagulant treatment has been reported to be the most common drug-related cause of emergency department visits and hospital admission among older adults, with accompanying high mortality rates. [14][15][16] The period immediately after hospital discharge can entail high risk for adverse events, as the transition to home is a complex process involving multiple providers, locations, testing and medication changes with imperfect reconciliation at a time when patients are still recovering. In a 2013 study, roughly one-fifth of Medicare patients discharged from hospital Adverse event rates associated with oral anticoagulant treatment early versus later after hospital discharge in older adults: a retrospective population-based cohort study