International Journal of Clinical Pharmacy

, Volume 34, Issue 1, pp 105–112 | Cite as

Anticoagulation control of pharmacist-managed collaborative care versus usual care in Thailand

  • Surasak Saokaew
  • Ubonwan Sapoo
  • Surakit NathisuwanEmail author
  • Nathorn Chaiyakunapruk
  • Unchalee Permsuwan
Research Article


Objective There has been a lack of evidence of the effects of pharmacist-managed warfarin therapy (PMWT) in developing countries (e.g. Southeast Asian countries) where the patients’ characteristics, genetic make-up, clinical practice and healthcare system are different from the Western world. This study aimed to compare the anticoagulation control and clinical outcomes associated with warfarin therapy provided by PMWT to usual care (UC) in the Thai population. Setting A 1,000-bed tertiary-care hospital in Nakornratchasima province of Thailand. Method A quasi-experimental study comparing PMWT and UC in patients receiving long-term warfarin therapy. For PMWT group, clinical pharmacists optimised the warfarin therapy and suggested recommendations (e.g. dose adjustment, safer alternative drugs, and follow-up time) to physicians. The UC group received the standard care. Main outcome measure Time in therapeutic range (TTR), both actual- and expanded-TTR, bleeding and thromboembolic complications, and physician’ acceptance of pharmacist suggestions. Results Of 433 patients enrolled, 220 and 213 were in the PMWT and UC groups respectively. At baseline, patient’s characteristics of both groups were comparable. At the end of follow-up period, patients in the PMWT group had significantly higher actual-TTR (48.3% vs. 40.1%; P < 0.001) and expanded-TTR (62.7% vs. 53.9%; P < 0.001) compared to those in the UC group. Rates of major bleeding were 4.4 vs 4.5 events per 100 person-years for the PMWT and UC groups, respectively. Pharmacists performed 284 interventions with an acceptance rate of 80.3% from physicians. Conclusion Pharmacist-managed warfarin therapy resulted in a significantly better anticoagulation control. This study showed that a collaborative approach in anticoagulation management can be successfully implemented in a developing country. Implementation of such care model in other developing countries should be considered.


Anticoagulation control Anticoagulation management service Bleeding Clinical outcome Collaborative care Pharmacist Time in therapeutic range (TTR) Thailand Thromboembolism Warfarin 



We would like to acknowledge and thank the Maharat Nakornratchasima Hospital for granting permission to use data provided in this study and Prof. Dr. Jayanton Patumanond for statistics suggestion. We gratefully acknowledge Dr. Bancha Sookananchai, Dr. Damri Sethachinda, Dr. Tongprakob Siriwanij, Mrs. Amonrat Pangthaisong, CCTS staffs, and all pharmacists for their significant contribution for this project.


The grant was supported by the Office of the Higher Education Commission, Ministry of Education, Thailand, under the program Strategic Scholarships for Frontier Research Network for the Ph.D. Program Thai Doctoral degree.

Conflicts of interest

No conflicts of interest to declare.


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Copyright information

© Springer Science+Business Media B.V. 2011

Authors and Affiliations

  • Surasak Saokaew
    • 1
    • 2
  • Ubonwan Sapoo
    • 3
  • Surakit Nathisuwan
    • 4
    Email author
  • Nathorn Chaiyakunapruk
    • 5
    • 6
    • 7
  • Unchalee Permsuwan
    • 8
  1. 1.Clinical Epidemiology Program, Faculty of MedicineChiang Mai UniversityChiang MaiThailand
  2. 2.School of Pharmaceutical SciencesUniversity of PhayaoPhayaoThailand
  3. 3.Department of PharmacyMaharat Nakornratchasima HospitalNakornratchasimaThailand
  4. 4.Faculty of PharmacyMahidol UniversityBangkokThailand
  5. 5.Center of Pharmaceutical Outcomes Research (CPOR), Faculty of Pharmaceutical SciencesNaresuan UniversityPhitsanulokThailand
  6. 6.School of Population HealthUniversity of QueenslandBrisbaneAustralia
  7. 7.School of PharmacyUniversity of WisconsinMadisonUSA
  8. 8.Faculty of PharmacyChiang Mai UniversityChiang MaiThailand

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