Drug interactions with oral anticoagulants in German nursing home residents: comparison between vitamin K antagonists and non-vitamin K antagonist oral anticoagulants based on two nested case–control studies
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Vitamin K antagonists (VKAs) are susceptible to drug–drug interactions. Non-VKA oral anticoagulants (NOACs) have a decreased sensitivity to pharmacokinetic interactions and might be therefore considered superior in patients treated with multiple drugs. The objective of this study was to compare the risk of serious bleeding associated with interacting drugs in German nursing home residents treated with VKA or NOAC.
Using claims data of new nursing home residents aged ≥ 65 years (2010–2014) we conducted separate nested case–control analyses within two cohorts of patients treated with VKA or NOAC, respectively. Cases were defined as patients hospitalized for serious bleeding. For each case, up to 20 controls were selected by risk-set sampling. Conditional logistic regression was used to obtain confounder-adjusted odds ratios (aORs) and 95% confidence intervals (CI) for the risk of bleeding associated with VKA or NOAC use and interacting drugs compared with the use of the respective oral anticoagulant alone.
Among 127,227 new nursing home residents, 16,804 patients received oral anticoagulation. Based on 372 cases and 7281 matched controls, the highest risk of bleeding in VKA users was observed for the concomitant use of antibiotics (aOR 3.00; CI 2.11–4.27) vs. VKA use alone, followed by non-steroidal anti-inflammatory drugs (1.66; 1.13–2.43). Among 243 NOAC cases and 4776 matched controls, elevated risks for bleeding were observed for the use of heparins (2.05; 1.25–3.36) and platelet inhibitors (1.92; 1.36–2.72).
Concomitant medication needs to be prescribed cautiously and monitored closely in nursing home residents treated with oral anticoagulants.
KeywordsAnticoagulants Drug interactions Risk of bleeding Nursing home residents
The authors thank the DAK-Gesundheit for providing the data for this study.
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
- 7.Pharma GmbH MEDA, Co KG (2018) Marcumar. Summary of products characteristics. Fachinfo-Service, FrankfurtGoogle Scholar
- 8.Squibb Bristol-Myers (2017) Coumadin. Summary of products characteristics. Fachinfo-Service, FrankfurtGoogle Scholar
- 17.Dörks M, Herget-Rosenthal S, Schmiemann G, Hoffmann F (2016) Polypharmacy and renal failure in nursing home residents: results of the inappropriate Medication in Patients with Renal Insufficiency in Nursing Homes (IMREN) Study. Drugs Aging 33:45–51. https://doi.org/10.1007/s40266-015-0333-2 CrossRefGoogle Scholar
- 22.Chang SH, Chou IJ, Yeh YH et al (2017) Association between use of non–vitamin K oral anticoagulants with and without concurrent medications and risk of major bleeding in nonvalvular atrial fibrillation. JAMA J Am Med Assoc 318:1250–1259. https://doi.org/10.1001/jama.2017.13883 CrossRefGoogle Scholar
- 35.Lip GYH, Keshishian A, Kamble S et al (2016) Real-world comparison of major bleeding risk among non-valvular atrial fibrillation patients initiated on apixaban, dabigatran, rivaroxaban, or warfarin: a propensity score matched analysis. Thromb Haemost. https://doi.org/10.1160/TH16-05-0403 Google Scholar
- 42.Duerschmied D, Brachmann J, Darius H et al (2018) Antithrombotic therapy in patients with non-valvular atrial fibrillation undergoing percutaneous coronary intervention: should we change our practice after the PIONEER AF-PCI and RE-DUAL PCI trials? Clin Res Cardiol. https://doi.org/10.1007/s00392-018-1242-2 Google Scholar
- 47.Bouillon K, Bertrand M, Boudali L et al (2016) Short-term risk of bleeding during heparin bridging at initiation of vitamin K antagonist therapy in more than 90 000 patients with nonvalvular atrial fibrillation managed in outpatient care. J Am Heart Assoc 1:1. https://doi.org/10.1161/JAHA.116.004065 Google Scholar