Introduction: Provider knowledge of factors influencing adherence with immunosuppression may help identify at-risk patients to allow for intervention.

Methods: MORE was a prospective, 4-year, observational study of de novo adult kidney transplant patients receiving mycophenolic acid (MPA) as enteric-coated mycophenolate sodium (EC-MPS) or mycophenolate mofetil (MMF) at 40 US sites. Adherence was assessed using the Immunosuppressant Therapy Adherence Scale (ITAS), a validated, self-reported, 4-item questionnaire: total score 0-12 (12=adherence; <12=non-adherence).

Results: ITAS data were available in 803/946 patients (84.9%); 49.7% (399/803) were non-adherent at some point. Mean(SD) total ITAS score at months 3, 6, 12, 24, 36 and 48 was 11.5(1.0), 11.4(1.2), 11.3(1.2), 11.2(1.2), 11.3(1.1) and 11.4(1.1), respectively, with non-adherence in 24.8%, 31.5%, 33.0%, 39.8%, 35.4% and 26.4% of patients. Patients receiving EC-MPS had a higher mean total score vs MMF at months 24 (11.3[1.0] vs 10.9 [1.4], p<0.01) and 36 (11.4[1.0] vs 11.1[11.3], p=0.02), and were more likely to take the prescribed dose of MPA at months 12 (94.6% vs 91.5%, p=0.04) and 24 (92.8% vs 87.7%, p=0.03). The odds ratio for non-adherence was 1.53 (95% CI 1.11, 2.12; p<0.01) in African Americans (AAs) vs non-AAs and 1.31 (95% CI 0.98, 1.75; p=0.06) for living vs deceased donation. Age, gender, and delayed graft function did not predict non-adherence. In non-adherent vs adherent patients, the incidence of biopsy-proven acute rejection was 12.8% (51/398) vs 11.1% (45/404) (log rank p=0.17); graft survival was 4.8% (19/399) vs 2.7% (11/404) (p=0.09); death was 1.5% (6/399) vs 4.5% (18/404) (p<0.01).

Conclusion: Adherence to immunosuppression decreases over time to month 24 post-transplant. Due to declining numbers of patients with follow-up data, limited conclusions could be not drawn thereafter. Demographic factors have limited predictive value other than African-American ethnicity, but choice of immunosuppressive regimen may be influential. Non-adherence was associated with a non-significant trend to greater graft loss, but reduced mortality.

Chan, L.: Grant/Research Support, Novartis, Other, Novartis, Consultant. Wiland, A.: Employee, Novartis. McCague, K.: Employee, Novartis.

« Back to 2013 American Transplant Congress