Increased medication compliance of liver transplant patients switched from a twice-daily to a once-daily tacrolimus-based immunosuppressive regimen

Abstract

Background: Compliance with immunosuppressive therapy plays a major role in the long-term success of liver transplantation. Thus, the development of strategies to promote compliance of liver transplant patients and its evaluation over time are of particular interest.

Objective: The main objective of this study was to compare medication compliance rates among liver transplant patients over time after transplantation where switched from a twice- to once-daily tacrolimus-based regimen.

Methods: Sixty-five liver transplant patients being administered tacrolimus-based therapy were classified into three subgroups with regard to time posttransplantation. Medication compliance with tacrolimus-based therapy was measured using an electronic medication event monitoring system over a 12-month period: for 6 months tacrolimus was administered twice-daily and for 6 months, once-daily. Dosing, taking, and timing compliance as well as drug holidays were compared intra-individually between twice- and once-daily intake and among the three subgroups. In addition, patient compliance and quality of life were evaluated using questionnaires.

Results: A per protocol analysis of electronically obtained data showed 63 patients to be eligible. The resulting dosing, taking, and timing compliance rates of the patients were higher during the once-daily dosing period. No significant differences in compliance rates with tacrolimus therapy were observed among three subgroups independent of the dosing regimen. More patients failed the correct timing of the evening compared to the morning dose. Missing doses occurred particularly during weekends. Compliance variables measured by questionnaires (Morisky score, self-report, Medication Experience Scale for Immunosuppressants (MESI) score) and the Hospital Anxiety and Depression Scale score were similar in the two dosing periods. The short-form health survey (SF-36) score was higher with once-daily intake.

Conclusion: The high measured compliance rates did not vary significantly dependent upon the time after transplantation. Nevertheless, compliance rates were greater using once-daily tacrolimus dosing.