Medication therapy management and adherence among US renal transplant recipients

Abstract

Background: Medication therapy management (MTM) services among patient populations with a range of disease states have improved adherence rates. However, no published studies have examined the impact of Medicare Part D MTM eligibility on renal transplant recipients' (RTRs) immunosuppressant therapy (IST) adherence. This study's purpose was therefore, to determine the effects of Medicare Part D MTM on IST adherence among adult RTRs at 12 months posttransplant.

Methods: Cross-sectional analyses were performed on Medicare Parts A, B, and D claims and transplant follow-up data reported in the United States Renal Data System. The sample included adult RTRs who were transplanted between 2006 and 2011, had graft survival for 12 months, were enrolled in Part D, and were prescribed tacrolimus. IST adherence was measured by medication possession ratio for tacrolimus. MTM eligibility was determined using criteria established by the Centers for Medicare and Medicaid Services. Descriptive statistics were calculated. Adherence was modeled using multiple logistic regression.

Results: In all, 17,181 RTRs were included. The majority of the sample were male (59.1%), and 42% were MTM-eligible. Mean medication possession ratio was 0.91±0.17 (mean ± standard deviation), with 16.83% having a medication possession ratio of <0.80. MTM eligibility, sex, age, and number of prescription drugs were significantly associated with adherence in the full model (P<0.05). MTM-eligible RTRs were more likely to be adherent than those who were not MTM-eligible (odds ratio =1.13, 95% confidence interval 1.02-1.26, P=0.02).

Conclusion: The findings provide evidence that access to MTM services increases IST adherence among RTRs.

Keywords: Medicare Part D; medication adherence; medication therapy management; renal transplant.

Figure 1

Renal transplant recipient sample inclusion. Note: Data retrieved from Medicare Parts A, B, and D claims and transplant follow-up data reported in the USRDS. Abbreviation: USRDS, United States Renal Data System.