The Medication Level Variability Index (MLVI) Predicts Poor Liver Transplant Outcomes: A Prospective Multi-Site Study.

Nonadherence to immunosuppressant medications is a leading cause of poor long-term outcomes in transplant recipients. The Medication Level Variability Index (MLVI) provides a vehicle for transplant outcome risk-stratification through continuous assessment of adherence. The MALT (Medication Adherence in children who had a Liver Transplant) prospective multi-site study evaluated whether MLVI predicts Late Acute Rejection (LAR). 400 pediatric (1–17 year old) liver transplant recipients were enrolled and followed for 2 years. The a-priori hypothesis was that a higher MLVI predicts LAR. Pre-defined secondary analyses evaluated other outcomes such as liver enzyme levels, and sensitivity analyses compared adolescent to pre-adolescents. In the primary analysis sample of 379 participants, a higher pre-rejection MLVI predicted LAR [mean pre-rejection MLVI with LAR: 2.4 (3.6 SD) vs. without LAR, 1.6 (1.1); p=0.026]. 53% of the adolescents with MLVI>2 in year 1 had LAR by the end of year 2, as compared with 6% of those with year 1 MLVI≤2. A higher MLVI was significantly associated with all secondary outcomes. MLVI, a marker of medication adherence that uses clinically-derived information, predicts LAR in pediatric liver transplant recipients.