Internal and Emergency Medicine

, Volume 14, Issue 8, pp 1307–1315 | Cite as

The effect of management models on thromboembolic and bleeding rates in anticoagulated patients: an ecological study

  • Alberto TosettoEmail author
  • Sophie Testa
  • Gualtiero Palareti
  • Oriana Paoletti
  • Ilaria Nichele
  • Francesca Catalano
  • Rossella Morandini
  • Maria Di Paolo
  • Maurizio Tala
  • Pilar Esteban
  • Francesco Cora’
  • Salvatore Mannino
  • Anna Maroni
  • Maria Sessa
  • Giancarlo Castaman
Part of the following topical collections:
  1. Direct Oral Anticoagulants


The primary study objective is to compare the outcomes of patients taking oral anticoagulant medications in two distinct populations treated according to different management models (comprehensive vs. usual care). (Design: regional prospective cohort study; setting: hospital admission data from two regions). Eligible partecipants were patients taking oral anticoagulant drugs (vitamin K antagonist or direct oral anticoagulants), residents in the Vicenza and Cremona districts from February 1st, 2016 to June 30th, 2017. Patients were identified by accessing the administrative databases of patient drug prescriptions. The primary study outcome was admission to the Emergency Department for stroke, systemic arterial embolism, recurrence of venous thromboembolism or major bleeding. The study evaluated outcomes in 14,226 patients taking oral anticoagulants, of whom 6725 being followed in Cremona with a comprehensive management model. There were 19 and 45 thromboembolic events over 6205 and 6530 patient-years in the Cremona and Vicenza cohort, respectively (IRR 0.44, 95% CI 0.24–0.77). The reduction of events in the Cremona cohort was almost entirely explained by a decrease of events in patients taking VKA (IRR 0.41, 95% CI 0.20–0.78) but not DOACs (IRR 1.08, 95% CI 0.25–5.24). The rate of major bleeding was non-significantly higher in Cremona than in Vicenza (IRI 1.32; 95% CI 0.74–2.40). Across the two cohorts, the risk of bleeding was lower in patients being treated with DOACs rather than warfarin (10/4574 vs. 42/8161 event/person-years, respectively, IRR 0.42 95% CI 0.19–0.86). We conclude that a comprehensive management model providing centralized dose prescription and follow-up may significantly reduce the rate of thromboembolic complications, without substantially increasing the number of bleeding complications. Patients treated with direct oral anticoagulants appear to have a rate of thromboembolic complications comparable to VKA patients under the best management model, with a reduction of major bleeding.


Vitamin K antagonists Direct oral anticoagulants Complications 


Author contributions

AT and ST contributed equally to the manuscript. AT designed the study, analyzed the data, and wrote the manuscript. He has received travel funding from Bayer and Novo-Nordisk; lecture fees from Stago, Werfen, and Roche. ST designed the study and wrote the manuscript. She declares lecture fees from Bayer, Stago, Roche, Boheringer, Sobi, Daiichi, BMS Pfizer, and Sanofi. GP revised the manuscript for important intellectual content. He declares participation to advisory boards for Alfasigma, Pfizer, Roche; lectures fees from Werfen. FC, MP, PE, RM, IN, OP, and MT collected the data. FC, SM, and AM contributed to the study design and administrative data collection. MS and GC revised the data and critically revised the manuscript for important intellectual content and adjudicated events

Compliance with ethical standards

Conflict of interest

The author(s) declare that they have no conflict of interest.

Statement of human and animal rights

All procedures performed in studies involving human participants were in accordance with the ethical standards of the Cremona and Vicenza Institutional Review Boards and with the 1964 Helsinki declaration and its later amendments (see also Ethics, funding and data sharing paragraph). This article does not contain any studies with animals performed by any of the author.

Informed consent

For this type of observational study, formal consent is not required.


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Copyright information

© Società Italiana di Medicina Interna (SIMI) 2019

Authors and Affiliations

  • Alberto Tosetto
    • 1
    Email author
  • Sophie Testa
    • 2
  • Gualtiero Palareti
    • 3
  • Oriana Paoletti
    • 2
  • Ilaria Nichele
    • 1
  • Francesca Catalano
    • 2
  • Rossella Morandini
    • 2
  • Maria Di Paolo
    • 1
  • Maurizio Tala
    • 2
  • Pilar Esteban
    • 2
  • Francesco Cora’
    • 4
  • Salvatore Mannino
    • 5
  • Anna Maroni
    • 6
  • Maria Sessa
    • 7
  • Giancarlo Castaman
    • 8
  1. 1.Haemostasis and Thrombosis Unit, Haematology DepartmentSan Bortolo HospitalVicenzaItaly
  2. 2.Haemostasis and Thrombosis CentreCremona HospitalCremonaItaly
  3. 3.Arianna Anticoagulazione FoundationBolognaItaly
  4. 4.Emergency DepartmentSan Bortolo HospitalVicenzaItaly
  5. 5.ATS ValpadanaCremonaItaly
  6. 6.Territorial Pharmacy UnitSan Bortolo HospitalVicenzaItaly
  7. 7.Neurology DivisionCremona HospitalCremonaItaly
  8. 8.Department of Oncology, Centre for Bleeding Disorders and CoagulationCareggi University HospitalFlorenceItaly

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