Bleeding Risk under Oral Factor Xa Inhibitors: Meta-analysis of the randomized comparison with Vitamin K Antagonists and Meta-Regression analysis

Main Article Content

Nabila Ferahta
Lukshe Kanagaratnam
Moustapha Dramé
Thomas Vogel
Pierre-Jacques Ambrosi
Pierre-Olivier Lang*

Abstract

Background: Randomized trials have shown that oral direct factor Xa inhibitors (ODIXa) offer potential advantages over vitamin K antagonists (VKAs). It is however unclear whether the magnitude of their benefit is similar at the current recommended doses.


Objective: We assessed bleeding risks and total mortality associated with ODIXa therapy compared to VKAs among patients with non-valvular atrial fibrillation or acute venous thromboembolic disease.


Methods: Medline, Embase and Cochrane library databases were searched to identify all randomized controlled trials comparing ODIXa to VKAs. The main outcomes were major bleeding, major and clinically relevant non-major (CRNM) bleeding, intracranial haemorrhage, gastrointestinal bleeding, total bleeding events and overall mortality. Pooled odds ratios were calculated with random effect model. Meta-regression was performed.


Results: The use of ODIXa was associated with a significant reduced-risk of major bleeding (OR, 0.72; 95% CI, 0.60-0.87), major and CNRM bleeding (OR, 0.72; 95% CI, 0.54-0.96), intracranial bleeding (OR, 0.48; 95% CI, 0.39-0.59) and total bleeding events (OR, 0.69; 95% CI, 0.60-0.80). No difference in risk of gastrointestinal bleeding was observed in NVAF. A linear association was found between a higher CHADS2 and risk of major bleeding; increasing age and a high quality of warfarin monitoring (TTR) were also correlated with a higher risk of gastrointestinal bleeding on ODIXa.


Conclusion: ODIXa therapy was associated with a lower rate of bleedings complications and overall mortality. The gastrointestinal bleeding risk, which was globally similar, was however increasing in ODIXa groups with advancing age and greater quality of VKAs management.

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Article Details

Ferahta, N., Kanagaratnam, L. K., Dramé, M., Vogel, T., Ambrosi, P.-J., & Lang, P.-O. (2017). Bleeding Risk under Oral Factor Xa Inhibitors: Meta-analysis of the randomized comparison with Vitamin K Antagonists and Meta-Regression analysis. Journal of Cardiovascular Medicine and Cardiology, 4(3), 038–048. https://doi.org/10.17352/2455-2976.000048
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Copyright (c) 2017 Ferahta N, et al.

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Wysowski DK, Nourjah P, Swartz L (2007) Bleeding complications with warfarin use: a prevalent adverse effect resulting in regulatory action. Arch Intern Med 167: 1414-1419. Link: https://goo.gl/c9m97C

Classen DC, Jaser L, Budnitz DS (2010) Adverse drug events among hospitalized Medicare patients: epidemiology and national estimates from a new approach to surveillance. Jt Comm J Qual Patient Saf 36: 12-21. Link: https://goo.gl/aoyJNs

Budnitz DS, Lovegrove MC, Shehab N, Richards CL (2011) Emergency Hospitalizations for Adverse Drug Events in Older Americans. New England Journal of Medicine 365: 2002-2012. Link: https://goo.gl/HM8AH4

Berti D, Moors E, Moons P, Heidbuchel H (2015) Prevalence and antithrombotic management of atrial fibrillation in hospitalised patients. Heart 101: 884-893. Link: https://goo.gl/hLQXN1

Barnes GD, Lucas E, Alexander GC, Goldberger ZD (2015) National Trends in Ambulatory Oral Anticoagulant Use. Am J Med 128: 1300-1305. Link: https://goo.gl/enXuVK

Yeh CH, Fredenburgh JC, Weitz JI (2012) Oral direct factor Xa inhibitors. Circ Res 111: 1069-1078. Link: https://goo.gl/av8QHs

Del-Carpio Munoz F, Gharacholou SM, Munger TM, Friedman PA, Asirvatham SJ, et al. (2016) Meta-Analysis of Renal Function on the Safety and Efficacy of Novel Oral Anticoagulants for Atrial Fibrillation. Am J Cardiol 117: 69-75. Link: https://goo.gl/v8JujY

Dentali F, Riva N, Crowther M, Turpie AGG, Lip GYH, et al. (2012) Efficacy and safety of the novel oral anticoagulants in atrial fibrillation: a systematic review and meta-analysis of the literature. Circulation 126: 2381-2391. Link: https://goo.gl/HKWPaX

Fox BD, Kahn SR, Langleben D, Eisenberg MJ, Shimony A (2012) Efficacy and safety of novel oral anticoagulants for treatment of acute venous thromboembolism: direct and adjusted indirect meta-analysis of randomised controlled trials. BMJ 345: e7498. Link: https://goo.gl/UB5qmX

Fu W, Guo H, Guo J, Lin K, Wang H, et al. (2014) Relative efficacy and safety of direct oral anticoagulants in patients with atrial fibrillation by network meta-analysis. J Cardiovasc Med (Hagerstown) 15: 873-879. Link: https://goo.gl/cXem8f

Koifman E, Lipinski MJ, Escarcega RO, Didier R, Kiramijyan S, et al. (2016) Comparison of Watchman device with new oral anti-coagulants in patients with atrial fibrillation: A network meta-analysis. Int J Cardiol 205: 17-22. Link: https://goo.gl/qJrTL2

Kundu A, Sen P, Sardar P, Chatterjee S, Kapoor A, et al. (2016) Intracranial hemorrhage with target specific oral anticoagulants in patients with atrial fibrillation: An updated meta-analysis of randomized controlled trials. Int J Cardiol 203: 1000-1002. Link: https://goo.gl/9Wo62c

Lega JC, Bertoletti L, Gremillet C, Boissier C, Mismetti P, et al. (2014) Consistency of safety profile of new oral anticoagulants in patients with renal failure. J Thromb Haemost 12: 337-343. Link: https://goo.gl/kqyb3X

Miller CS, Grandi SM, Shimony A, Filion KB, Eisenberg MJ (2012) Meta-analysis of efficacy and safety of new oral anticoagulants (dabigatran, rivaroxaban, apixaban) versus warfarin in patients with atrial fibrillation. Am J Cardiol 110: 453-460. Link: https://goo.gl/UyKt4T

Nunes JPL, Rodrigues RP, Goncalves FR (2014) Comparative analysis and meta-analysis of major clinical trials with oral factor Xa inhibitors versus warfarin in atrial fibrillation. Open Heart 1: e000080. Link: https://goo.gl/d48Kg7

Providencia R, Grove EL, Husted S, Barra S, Boveda S, et al. (2014) A meta-analysis of phase III randomized controlled trials with novel oral anticoagulants in atrial fibrillation: comparisons between direct thrombin inhibitors vs. factor Xa inhibitors and different dosing regimens. Thromb Res 134: 1253-1264. Link: https://goo.gl/xFXpu7

Robertson L, Kesteven P, McCaslin JE (2015) Oral direct thrombin inhibitors or oral factor Xa inhibitors for the treatment of pulmonary embolism. Cochrane Database Syst Rev 12: CD010957. Link: https://goo.gl/4aswQi

Ruff CT, Giugliano RP, Braunwald E, Hoffman EB, Deenadayalu N, et al. (2014) Comparison of the efficacy and safety of new oral anticoagulants with warfarin in patients with atrial fibrillation: a meta-analysis of randomised trials. Lancet 383: 955-962. Link: https://goo.gl/9GcnuJ

Sardar P, Chatterjee S, Wu W-C, Lichstein E, Ghosh J, et al. (2013) New oral anticoagulants are not superior to warfarin in secondary prevention of stroke or transient ischemic attacks, but lower the risk of intracranial bleeding: insights from a meta-analysis and indirect treatment comparisons. PLoS One 8: e77694. Link: https://goo.gl/6rh9qh

Sharma M, Cornelius VR, Patel JP, Davies JG, Molokhia M (2015) Efficacy and Harms of Direct Oral Anticoagulants in the Elderly for Stroke Prevention in Atrial Fibrillation and Secondary Prevention of Venous Thromboembolism: Systematic Review and Meta-Analysis. Circulation 132: 194-204. Link: https://goo.gl/uKSLFK

Verdecchia P, Angeli F, Bartolini C, De Filippo V, Aita A, et al. (2015) Safety and efficacy of non-vitamin K oral anticoagulants in non-valvular atrial fibrillation: a Bayesian meta-analysis approach. Expert Opin Drug Saf 14: 7-20. Link: https://goo.gl/XaT44T

Sen S, Dahlberg KW (2014) Physician's fear of anticoagulant therapy in nonvalvular atrial fibrillation. Am J Med Sci 348: 513-521. Link: https://goo.gl/RtWGnL

Garg J, Chaudhary R, Krishnamoorthy P, Palaniswamy C, Shah N, et al. (2016) Safety and efficacy of oral factor-Xa inhibitors versus Vitamin K antagonist in patients with non-valvular atrial fibrillation: Meta-analysis of phase II and III randomized controlled trials. Int J Cardiol 218: 235-239. Link: https://goo.gl/9C3kPz

Pathak R, Pandit A, Karmacharya P, Aryal MR, Ghimire S, et al.(2015) Meta-analysis on risk of bleeding with apixaban in patients with renal impairment. Am J Cardiol 115: 323-327. Link: https://goo.gl/pirPFY

Sardar P, Chatterjee S, Lavie CJ, Giri JS, Ghosh J, et al. (2015) Risk of major bleeding in different indications for new oral anticoagulants: insights from a meta-analysis of approved dosages from 50 randomized trials. Int J Cardiol 179: 279-287. Link: https://goo.gl/LJS1XS

Touma L, Filion KB, Atallah R, Eberg M, Eisenberg MJ (2015) A meta-analysis of randomized controlled trials of the risk of bleeding with apixaban versus vitamin K antagonists. Am J Cardiol 115: 533-541. Link: https://goo.gl/xWnaCL

Bruins Slot KMH, Berge E (2013) Factor Xa inhibitors versus vitamin K antagonists for preventing cerebral or systemic embolism in patients with atrial fibrillation. Cochrane Database Syst Rev 8: CD008980. Link: https://goo.gl/h5c6xM

Riva N, Dentali F, Permunian ET, Ageno W (2016) Major Bleeding and Case Fatality Rate with the Direct Oral Anticoagulants in Orthopedic Surgery: A Systematic Review and Meta-Analysis. Semin Thromb Hemost 42: 42-54. Link: https://goo.gl/GbCfTj

Diener H-C, Eikelboom J, Connolly SJ, Joyner CD, Hart RG, et al. (2012) Apixaban versus aspirin in patients with atrial fibrillation and previous stroke or transient ischaemic attack: a predefined subgroup analysis from AVERROES, a randomised trial. Lancet Neurol 11: 225-231. Link: https://goo.gl/kM7NHk

Hutton B, Salanti G, Caldwell DM, Chaimani A, Schmid CH, et al. (2015) The PRISMA Extension Statement for Reporting of Systematic Reviews Incorporating Network Meta-analyses of Health Care Interventions: Checklist and ExplanationsPRISMA Extension for Network Meta-analysis. Ann Intern Med 162: 777-784. Link: https://goo.gl/7L8PgT

Higgins JPT, Altman DG, Gøtzsche PC, Jüni P, Moher D, et al. (2011) The Cochrane Collaboration’s tool for assessing risk of bias in randomised trials. BMJ 343: d5928. Link: https://goo.gl/nDj3sa

Agnelli G, Gallus A, Goldhaber SZ, Haas S, Huisman MV, et al. (2007) Treatment of proximal deep-vein thrombosis with the oral direct factor Xa inhibitor rivaroxaban (BAY 59-7939): the ODIXa-DVT (Oral Direct Factor Xa Inhibitor BAY 59-7939 in Patients With Acute Symptomatic Deep-Vein Thrombosis) study. Circulation 116: 180-187. Link: https://goo.gl/xeqD1e

Hori M, Matsumoto M, Tanahashi N, Momomura S-i, Uchiyama S, et al. (2012) Rivaroxaban vs. warfarin in Japanese patients with atrial fibrillation – the J-ROCKET AF study –. Circ J 76: 2104-2111. Link: https://goo.gl/XBUaDK

Agnelli G, Buller HR, Cohen A, Curto M, Gallus AS, et al. (2013) Oral apixaban for the treatment of acute venous thromboembolism. N Engl J Med 369: 799-808. Link: https://goo.gl/QmTKh3

Bauersachs R, Berkowitz SD, Brenner B, Buller HR, Decousus H, et al. (2010) Oral rivaroxaban for symptomatic venous thromboembolism. N Engl J Med 363: 2499-2510. Link: https://goo.gl/EuxwQy

Buller H, Deitchman D, Prins M, Segers A (2008) Efficacy and safety of the oral direct factor Xa inhibitor apixaban for symptomatic deep vein thrombosis. The Botticelli DVT dose-ranging study. J Thromb Haemost 6: 1313-1318. Link: https://goo.gl/mDQ961

Buller HR, Decousus H, Grosso MA, Mercuri M, Middeldorp S, et al. (2013) Edoxaban versus warfarin for the treatment of symptomatic venous thromboembolism. N Engl J Med 369: 1406-1415. Link: https://goo.gl/Wr942h

Buller HR, Lensing AWA, Prins MH, Agnelli G, Cohen A, et al. (2008) A dose-ranging study evaluating once-daily oral administration of the factor Xa inhibitor rivaroxaban in the treatment of patients with acute symptomatic deep vein thrombosis: the Einstein-DVT Dose-Ranging Study. Blood 112: 2242-2247. Link: https://goo.gl/uueCTS

Buller HR, Prins MH, Lensin AWA, Decousus H, Jacobson BF, et al. (2012) Oral rivaroxaban for the treatment of symptomatic pulmonary embolism. N Engl J Med 366: 1287-1297. Link: https://goo.gl/JWjqcj

Chung N, Jeon H-K, Lien L-M, Lai W-T, Tse H-F, et al. (2011) Safety of edoxaban, an oral factor Xa inhibitor, in Asian patients with non-valvular atrial fibrillation. Thromb Haemost 105: 535-544. Link: https://goo.gl/pCjBPQ

Connolly SJ, Eikelboom J, Dorian P, Hohnloser SH, et al. (2013) Betrixaban compared with warfarin in patients with atrial fibrillation: results of a phase 2, randomized, dose-ranging study (Explore-Xa). Eur Heart J 34: 1498-1505. Link: https://goo.gl/oZG8op

Giugliano RP, Ruff CT, Braunwald E, Murphy SA, Wiviott SD, et al. (2013) Edoxaban versus warfarin in patients with atrial fibrillation. N Engl J Med 369: 2093-2104. Link: https://goo.gl/cAqa42

Granger CB, Alexander JH, McMurray JJV, Lopes RD, Hylek EM, et al. (2011) Apixaban versus warfarin in patients with atrial fibrillation. N Engl J Med 365: 981-992. Link: https://goo.gl/DqnJQb

Lip GYH, Halperin JL, Petersen P, Rodgers GM, Pall D, et al. (2015) A Phase II, double-blind, randomized, parallel group, dose-finding study of the safety and tolerability of darexaban compared with warfarin in patients with non-valvular atrial fibrillation: the oral factor Xa inhibitor for prophylaxis of stroke in atrial fibrillation study 2 (OPAL-2). J Thromb Haemost 13: 1405-1413. Link: https://goo.gl/drd3nk

Nakamura M, Nishikawa M, Komuro I, Kitajima I, Uetsuka Y, et al. (2015) Apixaban for the Treatment of Japanese Subjects With Acute Venous Thromboembolism (AMPLIFY-J Study). Circ J 79: 1230-1236. Link: https://goo.gl/KDRarf

Ogawa S, Shinohara Y, Kanmuri K (2011) Safety and efficacy of the oral direct factor xa inhibitor apixaban in Japanese patients with non-valvular atrial fibrillation. The ARISTOTLE-J study. Circ J 75: 1852-1859. Link: https://goo.gl/pfKzpg

Patel MR, Mahaffey KW, Garg J, Pan G, Singer DE, et al. (2011) Rivaroxaban versus warfarin in nonvalvular atrial fibrillation. N Engl J Med 365: 883-891. Link: https://goo.gl/WHvZp7

Turpie AGG, Lip GYH, Minematsu K, Goto S, Renfurm RW, et al. (2010) Safety and tolerability of YM150 in subjects with non-valvular atrial fibrillation: a phase II study. European Society of Cardiology (ESC) Congress, Stockholm, Sweden. Link: https://goo.gl/eqGQaH

Weitz JI, Connolly SJ, Patel I, Salazar D, Rohatagi S, et al. (2010) Randomised, parallel-group, multicentre, multinational phase 2 study comparing edoxaban, an oral factor Xa inhibitor, with warfarin for stroke prevention in patients with atrial fibrillation. Thromb Haemost 104: 633-641. Link: https://goo.gl/n3RJnt

Yamada N, Hirayama A, Maeda H, Sakagami S, Shikata H, et al. (2015) Oral rivaroxaban for Japanese patients with symptomatic venous thromboembolism - the J-EINSTEIN DVT and PE program. Thromb J 13: 2. Link: https://goo.gl/t8qEJg

Yamashita T, Koretsune Y, Yasaka M, Inoue H, Kawai Y, et al. (2012) Randomized, multicenter, warfarin-controlled phase II study of edoxaban in Japanese patients with non-valvular atrial fibrillation. Circ J 76: 1840-1847. Link: https://goo.gl/L4aC9m

Connolly SJ, Eikelboom J, Joyner C, Diener H-C, Hart R, et al. (2011) Apixaban in Patients with Atrial Fibrillation. N Engl J Med 364: 806-817. Link: https://goo.gl/NazGqQ

Schulman S, Kearon C (2005) Definition of major bleeding in clinical investigations of antihemostatic medicinal products in non-surgical patients. J Thromb Haemost 3: 692-694. Link: https://goo.gl/yg3ihn

Mendell J, Zahir H, Matsushima N, Noveck R, Lee F, et al. (2013) Drug-Drug Interaction Studies of Cardiovascular Drugs Involving P-Glycoprotein, an Efflux Transporter, on the Pharmacokinetics of Edoxaban, an Oral Factor Xa Inhibitor. Am J Cardiovasc Drugs 13: 331-342. Link: https://goo.gl/Hwv67J

Gschwind L, Rollason V, Daali Y, Bonnabry P, Dayer P, et al. (2013) Role of P-glycoprotein in the uptake/efflux transport of oral vitamin K antagonists and rivaroxaban through the Caco-2 cell model. Basic Clin Pharmacol Toxicol 113: 259-265. Link: https://goo.gl/wu5LMq

Mueck W, Kubitza D, Becka M (2013) Co-administration of rivaroxaban with drugs that share its elimination pathways: pharmacokinetic effects in healthy subjects. Br J Clin Pharmacol 76: 455-466. Link: https://goo.gl/5RZSsH

Witt DM, Delate T, Hylek EM, Clark NP, Crowther MA et al. (2013) Effect of warfarin on intracranial hemorrhage incidence and fatal outcomes. Thromb Res 132: 770-775. Link: https://goo.gl/ZLCwgY

White HD, Gruber M, Feyzi J, Kaatz S, Tse H-F, et al. (2007) Comparison of outcomes among patients randomized to warfarin therapy according to anticoagulant control: results from SPORTIF III and V. Arch Intern Med 167: 239- 245. Link: https://goo.gl/fY2ZPv

Bjorck F, Sanden P, Renlund H, Svensson PJ, Sjalander A (2015) Warfarin treatment quality is consistently high in both anticoagulation clinics and primary care setting in Sweden. Thromb Res 136: 216-220. Link: https://goo.gl/Y94ZY7

(2016) Which oral anticoagulant for atrial fibrillation?. JAMA 315: 2117-2118. Link: https://goo.gl/uPw4sW

Fitzmaurice DA, Blann AD, Lip GYH (2002) Bleeding risks of antithrombotic therapy. BMJ 325: 828-831. Link: https://goo.gl/Qpk9pP

Hylek EM, Evans-Molina C, Shea C, Henault LE, Regan S (2007) Major hemorrhage and tolerability of warfarin in the first year of therapy among elderly patients with atrial fibrillation. Circulation 115: 2689-2696. Link: https://goo.gl/1A6om1

Hecker J, Marten S, Keller L, Helmert S, Michalski F, et al. (2016) Effectiveness and safety of rivaroxaban therapy in daily-care patients with atrial fibrillation. Results from the Dresden NOAC Registry. Thromb Haemost 115: 939-949. Link: https://goo.gl/ivjMSC

Fang MC, Go AS, Chang Y, Hylek EM, Henault LE, et al. (2007) Death and disability from warfarin-associated intracranial and extracranial hemorrhages. Am J Med 120: 700-705. Link: https://goo.gl/nwPnd7

Hansen BM, Nilsson OG, Anderson H, Norrving B, Saveland H, et al. (2013) Long term (13 years) prognosis after primary intracerebral haemorrhage: a prospective population based study of long term mortality, prognostic factors and causes of death. J Neurol Neurosurg Psychiatry 84: 1150-1155. Link: https://goo.gl/1dyF9b

Hippisley-Cox J, Coupland C (2014) Predicting risk of upper gastrointestinal bleed and intracranial bleed with anticoagulants: cohort study to derive and validate the QBleed scores. BMJ 349: g4606. Link: https://goo.gl/DjQjny

Coleman CI, Sobieraj DM, Winkler S, Cutting P, Mediouni M, et al. (2012) Effect of pharmacological therapies for stroke prevention on major gastrointestinal bleeding in patients with atrial fibrillation. International journal of clinical practice 66: 53-63. Link: https://goo.gl/KDfnse

Kakkar AK, Mueller I, Bassand J-P, Fitzmaurice DA, Goldhaber SZ, et al. (2013) Risk profiles and antithrombotic treatment of patients newly diagnosed with atrial fibrillation at risk of stroke: perspectives from the international, observational, prospective GARFIELD registry. PLoS One 8:e63479. Link: https://goo.gl/pzCuC2

Steinberg BA, Blanco RG, Ollis D, Kim S, Holmes DN, et al. (2014) Outcomes Registry for Better Informed Treatment of Atrial Fibrillation II: rationale and design of the ORBIT-AF II registry. Am Heart J 168: 160-167. Link: https://goo.gl/EadZkw

Tamayo S, Frank Peacock W, Patel M, Sicignano N, Hopf KP, et al. (2015) Characterizing Major Bleeding in Patients With Nonvalvular Atrial Fibrillation: A Pharmacovigilance Study of 27 467 Patients Taking Rivaroxaban. Clin Cardiol 38: 63-68. Link: https://goo.gl/9SXrmQ

Abraham NS, Singh S, Alexander GC, Heien H, Haas LR, et al. (2015) Comparative risk of gastrointestinal bleeding with dabigatran, rivaroxaban, and warfarin: population based cohort study. BMJ 350: h1857. Link: https://goo.gl/hUUXdU

Camm AJ, Amarenco P, Haas S, Hess S, Kirchhof P, et al.( 2016) XANTUS: a real-world, prospective, observational study of patients treated with rivaroxaban for stroke prevention in atrial fibrillation. Eur Heart J 37: 1145-1153. Link: https://goo.gl/ULcraK

Yao X, Abraham NS, Sangaralingham LR, Bellolio MF, McBane RD, et al. (2016) Effectiveness and Safety of Dabigatran, Rivaroxaban, and Apixaban Versus Warfarin in Nonvalvular Atrial Fibrillation. JAHA 5: e003725. Link: https://goo.gl/Wd4w3Z

Ageno W, Mantovani LG, Haas S, Kreutz R, Monje D, et al. Safety and effectiveness of oral rivaroxaban versus standard anticoagulation for the treatment of symptomatic deep-vein thrombosis (XALIA): an international, prospective, non-interventional study. Lancet Haematol 3: e12-e21. Link: https://goo.gl/G4hgTD

Abraham NS, Noseworthy PA, Yao X, Sangaralingham LR, Shah ND (2017) Gastrointestinal Safety of Direct Oral Anticoagulants: A Large Population Based Study. Gastroenterology 152: 1014-1022.e1. Link: https://goo.gl/2S3eU6

Li XS, Deitelzweig S, Keshishian A, Hamilton M, Horblyuk R, et al. (2017) Effectiveness and safety of apixaban versus warfarin in non-valvular atrial fibrillation patients in "real-world" clinical practice. A propensity-matched analysis of 76,940 patients. Thromb Haemost 117: 1072-1082. Link: https://goo.gl/7XGZDF

Sadlon AH, Tsakiris DA (2016) Direct oral anticoagulants in the elderly: systematic review and meta-analysis of evidence, current and future directions. Swiss Med Wkly 146: w14356. Link: https://goo.gl/PR7zpW

Ieko M, Naitoh S, Yoshida M, Takahashi N (2016) Profiles of direct oral anticoagulants and clinical usage - dosage and dose regimen differences. J Intensive Care 4: 19. Link: https://goo.gl/ZuSN6n

Schulz KF, Chalmers I, Hayes RJ, Altman DG (1995) Empirical evidence of bias: Dimensions of methodological quality associated with estimates of treatment effects in controlled trials. JAMA 273: 408-412. Link: https://goo.gl/fheto2

Topinkova E, Baeyens JP, Michel J-P, Lang P-O (2012) Evidence-based strategies for the optimization of pharmacotherapy in older people. Drugs Aging 29: 477-494. Link: https://goo.gl/5T2bCR