International Journal of Clinical Pharmacy

, Volume 40, Issue 3, pp 721–729 | Cite as

Impact of warfarin discharge education program on hospital readmission and treatment costs

  • Luigi Brunetti
  • Seung-Mi Lee
  • Nancy Doherty
  • David Suh
  • Jeong-Eun Kim
  • Sun-Hong Lee
  • Yong Chan Choi
  • Dong-Churl SuhEmail author
Research Article


Background Although warfarin is highly effective, management of patients prescribed warfarin is complex due to its narrow therapeutic window. Objective To evaluate the impact of a formal warfarin discharge education program (WDEP) on hospital readmission and treatment costs in patients who received warfarin therapy. Setting Robert Wood Johnson University Hospital Somerset in Somerville, New Jersey, USA. Method In this interventional cohort study, patients were assigned to either the WDEP group or the usual care group. The effects of the WDEP on readmission within 90 days after discharge were analyzed using Cox proportional hazards models. Factors influencing treatment cost were identified using generalized linear model with log-link function and gamma distribution. Main outcome measure Hospital readmission within 90 days and treatment costs associated with hospital readmission. Results Among 692 eligible patients, 203 in each group were matched using propensity scores and there were no statistically significant differences in the patient baseline characteristics between two groups. The risk of all-cause readmission within 90 days was significantly lower in the WDEP group compared to the usual care group (relative risk = 0.46, 95% CI 0.28–0.76). The treatment costs associated with hospital readmission in the WDEP group were 19% lower than those in the usual care group after adjusting for the study variables. Conclusion A formal, individualized WDEP provided by pharmacists resulted in significant reduction of readmission and treatment costs. The economic burden of treatment costs associated with warfarin can be controlled if well-organized warfarin education is provided to patients who received warfarin therapy.


Hospital discharge Hospital readmission Patient education Pharmaceutical care Treatment costs USA Warfarin education 



We would like to thank Ms. Seyunghe Je and Mr. Sung-su Lee for their assiatance with searching articles and initial data entry.


This research was supported by Chung-Ang University Research Scholarship grants (Seoul, South Korea) awarded in 2016.

Conflicts of interest

All the authors declare that there is no conflict of interest.

Supplementary material

11096_2018_631_MOESM1_ESM.pdf (237 kb)
Supplementary material 1 (PDF 237 kb)


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Copyright information

© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Ernest Mario School of PharmacyRutgers UniversityNew BrunswickUSA
  2. 2.RWJ Barnabas HealthRobert Wood Johnson University Hospital SomersetSomervilleUSA
  3. 3.College of PharmacyChung-Ang UniversitySeoulSouth Korea
  4. 4.School of Public HealthColumbia UniversityNew YorkUSA

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