Sammanfattning
BACKGROUND: The aim of this study was to obtain a better insight into the adverse drug reaction profiles of the new direct-acting oral anticoagulants (DOACs).
MATERIAL AND METHOD: A review was undertaken of all reports of adverse drug reactions for warfarin, dabigatran, rivaroxaban and apixaban received by the Norwegian regional medicines information and pharmacovigilance centres (RELIS) in the period June 2013–May 2015.
RESULTS: Approximately 65 000 persons used direct-acting oral anticoagulants and 80 000 used warfarin in the study period. A total of 409 reports of adverse drug reactions were included in the study. Altogether 55 % of the reports related to men. The patients were over 70 years of age in 76 % of the reports for direct-acting oral anticoagulants and in 85 % for warfarin. The most common adverse drug reactions were haemorrhages (48 % for direct-acting oral anticoagulants and 75 % for warfarin). Most of them were cerebral haemorrhages (91 for direct-acting oral anticoagulants and 92 for warfarin). Blood clots (therapeutic failure), cognitive impairment, headache and hair loss were among the other adverse drug reactions. The highest levels of comorbidity were seen in patients who died. The number of reported deaths was highest for rivaroxaban (1.1 deaths/1 000 users) with a declining incidence for apixaban (0.9 ‰), dabigatran (0.7 ‰) and warfarin (0.6 ‰). The degree of reporting differed for the different drugs, and therefore the spontaneous reporting system cannot be used to compare the incidence of adverse drug reactions associated with different medications.
INTERPRETATION: Adverse drug reactions, including serious adverse reactions, may occur with the use of any anticoagulant. Factors that may increase the risk of adverse reactions are advanced age, high comorbidity, impaired renal function, and polypharmacy.