International Journal of Clinical Pharmacy

, Volume 39, Issue 6, pp 1157–1161 | Cite as

Assessment of oral anticoagulation control at two pharmacist-managed clinics in Brazil

  • Rogério Guimarães de Lima Silva
  • Caryne Margotto Bertollo
  • Isadora Gonçalves Ferreira
  • Luisa Caldeira Brant
  • Maria Auxiliadora Parreiras MartinsEmail author
Short Research Report


Background Warfarin remains widely used by patients with cardiovascular diseases. When using warfarin, the quality of oral anticoagulation control is a critical determinant to minimize the risk of bleeding and thromboembolic events. Pharmacist engagement in patient care is relevant towards improving the quality of warfarin therapy. Objective To assess the quality of oral anticoagulation control measured by time in therapeutic range (TTR) at two pharmacist-managed anticoagulation clinics (AC). Method This study included adults with indication of continuous warfarin use. Patients were recruited at two AC of public hospitals in Brazil (2014–2015). Anticoagulation control was assessed by TTR using the Rosendaal method. Laboratory INR values were collected for the maximum period of follow-up (2009–2015). Results A total of 554 patients were studied. The median age was 63.7 [Quartile 1 (Q1) 54.3; Quartile 3 (Q3) 73.6] years, 57.4% female. The median TTR was 64.3% [Q1 54.0%; Q3 74.0%], and 344 (61.6%) patients had TTR ≥ 60%. Conclusion Pharmacist-managed AC have achieved an adequate TTR in Brazilian patients with low socioeconomic status. Interventions include face-to-face appointments for individual patient education, warfarin-dosing adjustments and monitoring of drug interactions. Pharmacists are important to improve adherence and the quality of warfarin therapy in low- and middle income countries.


Anticoagulants International normalized ratio Outpatient clinics Pharmacists Warfarin Brazil INN 




Conflicts of interest

None of the authors have had financial or personal relationships with other people or organizations that could inappropriately influence (bias) their work.


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Copyright information

© Springer International Publishing AG 2017

Authors and Affiliations

  • Rogério Guimarães de Lima Silva
    • 1
  • Caryne Margotto Bertollo
    • 1
  • Isadora Gonçalves Ferreira
    • 1
  • Luisa Caldeira Brant
    • 1
  • Maria Auxiliadora Parreiras Martins
    • 1
    Email author
  1. 1.Universidade Federal de Minas GeraisBelo HorizonteBrazil

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