Is calculating the standard deviation of tacrolimus blood levels the new gold standard for evaluating non-adherence to medications in transplant recipients?

Cardiovascular Precision Medicine and Remote Intervention Trial Rationale and Design

Background: It has recently been shown that excessive fluctuation in blood pressure readings for an individual over time is closely associated with poor outcomes, including increased risk of cardiovascular mortality, coronary heart disease and stroke. Fluctuations may be associated with inconsistent adherence to medical recommendations. This new marker of risk has not yet been incorporated into a monitoring and intervention strategy that seeks to reduce cardiovascular risk by identifying patients through an algorithm tied to their electronic health record (EHR). Methods: We describe the methods used in an innovative "proof of concept" trial using CP&R (Cardiovascular Precision Medicine and Remote Intervention). A blood pressure variability index is calculated for clinic patients via an EHR review. Consenting patients with excessive variability are offered a remote intervention aimed at improving adherence to medical recommendations. The outcomes include the ability to identify and engage the identified patients and the effects of the intervention on blood pressure variability using a pre-post comparison design without parallel controls. Conclusions: Our innovative approach uses a recently identified marker based on reviewing and manipulating EHR data tied to a remote intervention. This design reduces patient burden and supports equitable and targeted resource allocation, utilizing an objective criterion for behavioral risk. This study is registered under ClinicalTrials.gov Identifier: NCT05814562.

Randomized pilot trial of cell phone support to improve medication adherence among adolescents and young adults with chronic health conditions

Introduction

Adolescents and young adults (AYA) living with chronic medical conditions often struggle to develop medication adherence skills. This pilot trial evaluated the impact of a mobile health coaching intervention, Cell Phone Support (CPS), on medication adherence.

Methods

Interventions in this randomized trial were CPS delivered by phone calls (CPS-C), CPS delivered by text messages (CPS-T), or automated text message reminders (ATR). Participants were AYA with different chronic medical conditions (i.e., sickle cell disease, solid organ transplant, type 2 diabetes), aged 15-20 years (N = 34). We examined the feasibility, acceptability, and preliminary efficacy of each intervention.

Results

We examined the feasibility, acceptability, and preliminary efficacy of both CPS interventions. CPS was feasible and acceptable. There was evidence that participants found CPS to be more useful than ATR. In this pilot trial, participants receiving CPS reported relatively stronger increases in adherence, compared to those assigned to ATR. CPS-C slightly outperformed CPS-T.

Conclusions

Providing coaching to AYA struggling with illness self-management via their cell phones may promote their acquisition of medication adherence skills. Although larger studies are needed to confirm the results of this pilot study, phone calls and text messages are both promising modalities for delivering human cell phone support.

Trial registration

This trial was registered prospectively at ClinicalTrials.gov (NCT04241627) on 1/27/2020.

Demographic Factors, Medication Adherence, and Post-transplant Health Outcomes: A Longitudinal Multilevel Modeling Approach

Few studies in pediatric solid organ transplantation have examined non-adherence to immunosuppressive medication over time and its associations with demographic factors and post-transplant outcomes including late acute rejection and hospitalizations. We examined longitudinal variation in patient Medication Level Variability Index (MLVI) adherence data from pediatric kidney, liver, and heart transplant recipients. Patient and administrative data from the United Network for Organ Sharing were linked with electronic health records and MLVI values for 332 patients. Multilevel mediation modeling indicated comparatively more variation in MLVI values between patients than within patients, longitudinally, over 10 years post transplant. MLVI values significantly predicted late acute rejection and hospitalization. MLVI partially mediated patient factors and post-transplant outcomes for patient age indicating adolescents may benefit most from intervention efforts. Results demonstrate the importance of longitudinal assessment of adherence and differences among patients. Efforts to promote medication adherence should be adapted to high-risk patients to increase likelihood of adherence.

Medication adherence in pediatric kidney transplantation: How to build a bridge over troubled water

Adhering to the immunosuppressive regimen remains one of the biggest challenges for children and adolescents after kidney transplantation. The first paper on nonadherence, co-authored by Dr. Fine, appeared in Pubmed over 45 years ago. Since then, many clinicians and researchers tried to better understand nonadherence and are looking for effective ways to support young people in implementing the complex medication regimen in their daily lives. As a tribute to Dr. Fine, we conducted a comprehensive review providing an overview of adherence-enhancing interventions in the field of pediatric kidney transplantation, thereby focusing on strategies that not only are effective but can also be embedded in daily clinical practice successfully and sustainably. This overview is preceded by a discussion about how to find out who is in need of supportive interventions. We will also argue that interventions should already start before pediatric kidney transplantation and discuss how to decide whether or not a young patient with nonadherence-induced graft loss should undergo retransplantation. We hope this comprehensive overview will rekindle the hope that we can finally turn the tide and beat one of pediatric kidney transplantation's main enemies.

Safety and Efficacy of Conversion to Once-Daily Tacrolimus from Twice-Daily Tacrolimus in Pediatric Liver Transplant Recipients

BACKGROUND

Nonadherence to immunosuppression is the most common cause of late acute rejection in pediatric liver transplant (LT) recipients. A prolonged-release once-daily tacrolimus formulation was developed to improve adherence and long-term allograft survival.

METHODS

We screened 179 pediatric LT recipients who converted from twice-daily tacrolimus (TD-TAC) to once-daily tacrolimus (OD-TAC) between February 2011 and September 2019.

RESULTS

One hundred seventy-nine recipients converted to OD-TAC and were followed for 18 months. 152 OD-TAC-converted recipients (84.9%) experienced uneventful follow-up, while 21 recipients showed LFT elevation. Four recipients had biopsy-proven acute rejection within six months of conversion, all of which were successfully treated with steroid pulse. 166 recipients (92.7%) remain on OD-TAC and 13 (7.3%) were switched back to TD-TAC. The mean tacrolimus trough level significantly decreased three months following conversion (3.14 ± 1.9 ng/mL) compared with pre-conversion levels (3.69 ± 1.98 ng/mL). Mean tacrolimus trough levels remained unchanged from 3 months to 12 months following conversion. Percent coefficient of variation of tacrolimus trough levels decreased significantly from 32.5 ± 16.4 ng/mL to 27.5 ± 15.6 ng/mL after conversion to OD-TAC, reflecting a decrease in variation of tacrolimus trough levels following conversion.

CONCLUSIONS

Conversion to OD-TAC in pediatric LT recipients with stable graft function is safe and effective.

LEVEL OF EVIDENCE

Level IV.

Impact of tacrolimus intra-patient variability in adverse outcomes after organ transplantation

Tacrolimus (Tac) is currently the most common calcineurin-inhibitor employed in solid organ transplantation. High intra-patient variability (IPV) of Tac (Tac IPV) has been associated with an increased risk of immune-mediated rejection and poor outcomes after kidney transplantation. Few data are available concerning the impact of high Tac IPV in non-kidney transplants. However, even in kidney transplantation, there is still a controversy whether high Tac IPV is indeed detrimental in respect to graft and/or patient survival. This may be due to different methods employed to evaluate IPV and distinct time frames adopted to assess graft and patient survival in those reports published up to now in the literature. Little is also known about the influence of high Tac IPV in the development of other untoward adverse events, update of the current knowledge regarding the impact of Tac IPV in different outcomes following kidney, liver, heart, lung, and pancreas tran splantation to better evaluate its use in clinical practice.

Differences in medication adherence by sex and organ type among adolescent and young adult solid organ transplant recipients

BACKGROUND

Identification of differences in medication adherence by sex or organ type may help in planning interventions to optimize outcomes. We compared immunosuppressive medication adherence between males and females, and between kidney, liver and heart transplant recipients.

METHODS

This multicenter study of prevalent kidney, liver and heart transplant recipients 14-25 years assessed adherence 3 times (0, 3, 6 months post-enrollment) with the BAASIS self-report tool. At each visit, participants were classified as adherent if they missed no doses in the prior 4 weeks and non-adherent otherwise. Adherence was also assessed using the coefficient of variation (CV) of tacrolimus trough levels; CV < 30% was classified as adherent. We used multivariable mixed effects logistic regression models adjusted for potential confounders to compare adherence by sex and by organ.

RESULTS

Across all visits, males (n = 150, median age 20.4 years, IQR 17.2-23.3) had lower odds of self-reported adherence than females (n = 120, median age 19.8 years, IQR 17.1-22.7) (OR 0.41, 95% CI 0.21-0.80) but higher odds of adherence by tacrolimus CV (OR 2.50, 95% CI 1.30-4.82). No significant differences in adherence (by self-report or tacrolimus CV) were noted between the 184 kidney, 58 liver, and 28 heart recipients.

CONCLUSION

Females show better self-reported adherence than males but greater variability in tacrolimus levels. Social desirability bias, more common in females than males, may contribute to better self-reported adherence among females. Higher tacrolimus variability among females may reflect biologic differences in tacrolimus metabolism between males and females rather than sex differences in adherence. There were no significant differences in adherence by organ type.

Infliximab Induction Lacks Efficacy and Increases BK Virus Infection in Deceased Donor Kidney Transplant Recipients: Results of the CTOT-19 Trial

BACKGROUND

Ischemia-reperfusion (IR) of a kidney transplant (KTx) upregulates TNF α production that amplifies allograft inflammation and may negatively affect transplant outcomes.

METHODS

We tested the effects of blocking TNF peri-KTx via a randomized, double-blind, placebo-controlled, 15-center, phase 2 clinical trial. A total of 225 primary transplant recipients of deceased-donor kidneys (KTx; 38.2% Black/African American, 44% White) were randomized to receive intravenous infliximab (IFX) 3 mg/kg or saline placebo (PLBO) initiated before kidney reperfusion. All patients received rabbit anti-thymocyte globulin induction and maintenance immunosuppression (IS) with tacrolimus, mycophenolate mofetil, and prednisone. The primary end point was the difference between groups in mean 24-month eGFR.

RESULTS

There was no difference in the primary end point of 24-month eGFR between IFX (52.45 ml/min per 1.73 m 2 ; 95% CI, 48.38 to 56.52) versus PLBO (57.35 ml/min per 1.73 m 2 ; 95% CI, 53.18 to 61.52; P =0.1). There were no significant differences between groups in rates of delayed graft function, biopsy-proven acute rejection (BPAR), development of de novo donor-specific antibodies, or graft loss/death. Immunosuppression did not differ, and day 7 post-KTx plasma analyses showed approximately ten-fold lower TNF ( P <0.001) in IFX versus PLBO. BK viremia requiring IS change occurred more frequently in IFX (28.9%) versus PLBO (13.4%; P =0.004), with a strong trend toward higher rates of BKV nephropathy in IFX (13.3%) versus PLBO (4.9%; P =0.06).

CONCLUSIONS

IFX induction therapy does not benefit recipients of kidney transplants from deceased donors on this IS regimen. Because the intervention unexpectedly increased rates of BK virus infections, our findings underscore the complexities of targeting peritransplant inflammation as a strategy to improve KTx outcomes.Clinical Trial registry name and registration number:clinicaltrials.gov (NCT02495077).

Randomized pilot trial of praise text messages to improve medication adherence among adolescents and young adults with liver transplants

BACKGROUND

AYA who have undergone liver transplantations often struggle to adhere to their post-transplant immunosuppressant medications, which can lead to serious health complications. The objective of this pilot study is to examine the acceptability and feasibility of a brief mobile health (mHealth) intervention and its impact on medication adherence among AYA liver transplant recipients.

METHODS

Thirty-five AYAs (13-21 years old) were randomized to either (1) receive praise text messages whenever laboratory results indicated immunosuppressant medications within the expected range or (2) usual care. Motivation for adherence and adherence were assessed via self-report, and a MLVI was calculated based on values abstracted from the electronic health record.

RESULTS

Multilevel, multivariate models showed significant associations between group assignment and some self-reported motivation and adherence outcomes but not MLVI. Specifically, AYA receiving the praise text messages were significantly more likely to report taking their prescribed doses (OR = 2.49, p = .03), taking their medicine according to the directions (OR = 2.39, p = .04), and being highly confident in taking their medication (OR = 2.46, p = .04), compared with the usual services group. Qualitative responses indicated praise texts were mostly helpful but could be improved.

CONCLUSIONS

The results suggest texting patients about positive health indicators was acceptable and, with refinement, might promote AYA illness self-management.

Directly observed therapy to promote medication adherence in adolescent heart transplant recipients

PURPOSE

HT recipients experience high levels of medication non-adherence during adolescence. This pilot study examined the acceptability and feasibility of an asynchronous DOT mHealth application among adolescent HT recipients. The app facilitates tracking of patients' dose-by-dose adherence and enables transplant team members to engage patients. The DOT application allows patients to self-record videos while taking their medication and submit for review. Transplant staff review the videos and communicate with patients to engage and encourage medication adherence.

METHODS

Ten adolescent HT recipients with poor adherence were enrolled into a single-group, 12-week pilot study examining the impact of DOT on adherence. Secondary outcomes included self-report measures from patients and parents concerning HRQOL and adherence barriers. Long-term health outcomes assessed included AR and hospitalization 6 months following DOT.

FINDINGS

Among 14 adolescent HT patients approached, 10 initiated the DOT intervention. Of these, 8 completed the 12-week intervention. Patients and caregivers reported high perceptions of acceptability and accessibility. Patients submitted 90.1% of possible videos demonstrating medication doses taken. MLVI values for the 10 patients initiating DOT decreased from 6 months prior to the intervention (2.86 ± 1.83) to 6 months following their involvement (2.08 ± 0.87) representing a 21.7% decrease in non-adherence, though not statistically significant given the small sample size.

CONCLUSIONS

Result of this pilot study provides promising insights regarding the feasibility, acceptability, and potential impact of DOT for adolescent HT recipients. Further randomized studies are required to confirm these observations.

Medication Barriers and Adherence: Experiences of Pediatric Transplant Recipients

This study examined associations between scores on the Adolescent Medication Barriers Scale (AMBS) and the Parent Medication Barriers Scale (PMBS), patient and family factors, and medication adherence outcomes. Patients and caregivers from a pediatric solid organ transplantation (SOT) program were recruited for participation. Pediatric SOT recipients ages 10 to 21 years were eligible for participation. Analyses included reliability analyses and regression modeling with posttransplant medication adherence measured by Medication Level Variability Index scores. Seventy-three patients and caregivers completed an AMBS or PMBS questionnaire. Patient-caregiver inter-rater reliability was poor to fair. Greater medication barriers were reported among younger and female patients and families with more children. AMBS scores predicted greater nonadherence, while the PMBS was not predictive of adherence. Results point to the difficulty of assessing barriers to medication adherence and the lack of agreement between adolescent patients and caregivers. AMBS scores were more closely aligned with medication nonadherence, whereas PMBS scores may have been more influenced by family social factors. Adolescent reports of medication barriers may offer multidisciplinary transplant teams greater clinical utility when addressing these challenges with patients. Transplant social workers and psychologists should engage adolescents and caregivers in efforts to address medication nonadherence.

Mismatch epitope load predicts de novo-DSA-free survival in pediatric liver transplantation

BACKGROUND

Our knowledge of de novo anti-HLA donor-specific antibodies (dnDSA) in liver transplantation continues to be defined. We hypothesized that differences of HLA-DR/DQ mismatches can improve precision in alloimmune risk categorization and be applied to tailor immunosuppression.

METHODS

A retrospective chart review of 244 pediatric patients consecutively transplanted at our center between 2003 and 2019 was performed to identify patients tested for dnDSA. Records were queried for: demographics, pre-transplant diagnosis, biopsy-proven T-cell-mediated rejection (TCMR), radiology proven biliary complications, tacrolimus trough levels, dnDSA characteristics, and HLA typing. The eplet mismatch analyses were performed using HLAMatchmaker^™ 3.1. All statistical analyses were conducted using R software version 3.40.

RESULTS

There were 99 dnDSA-negative patients and 73 dnDSA-positive patients (n = 70 against class II and n = 3 against class I and II). ROC analysis identified optimal cutoff of eplet mismatch load for dnDSA and defined risk groups for an alloimmune outcome. Kaplan-Meier curves and log-rank tests showed high eplet mismatch load was associated with shorter dnDSA-free survival (log-rank p = .001). Multivariable Cox regression models showed that tacrolimus coefficient of variation and tacrolimus mean levels were significantly associated with dnDSA-free survival (p < .001 and p = .036). Fisher's exact test showed that dnDSA was associated with an increased likelihood of TCMR (OR 14.94; 95% CI 3.65 - 61.19; p < .001). Patients without TCMR were more likely to have dnDSA to HLA-DQ7 and less likely to have dnDSA to HLA-DQ2 (p = .03, p = .080).

CONCLUSIONS

Mismatched epitope load predicts dnDSA-free survival in pediatric liver transplant, while dnDSA specificity may determine alloimmune outcome.

Impact of tacrolimus variability on pediatric heart transplant outcomes

BACKGROUND

Tacrolimus is a narrow therapeutic index drug, requiring consistent levels to maximize transplant success while reducing adverse effects. Elevated tacrolimus level variability (ETLV) is associated with poor outcomes in both pediatric and adult solid organ transplant recipients. We sought to describe the prevalence of ETLV and identify associations with patient-specific factors and poor outcomes.

METHODS

Tacrolimus levels were evaluated from 118 patients at our single center. As a marker of variability, standard deviations (SD) were calculated for each patient from their entire tacrolimus level data set (global SD), and 1-2 years and 1-5 years post-HT (prediction window SDs). SD ≥3 denoted ETLV.

RESULTS

There was large variability in tacrolimus levels (median global SD 3.1; IQR 2.3, 4; SD ≥3, n = 64, 54%). Patients with elevated SD (≥3) vs lower SD (<3) were more likely to have poor outcomes including rejection (73% vs 46%), cardiac allograft vasculopathy (CAV, 22% vs 9%), and death (20% vs 6%). The prediction window analysis noted ETLV was associated with a 40% greater risk of CAV, re-HT, or death (p = .024) and increasing age at transplantation was associated with a 12% increase in the risk of rejection (p = <.001) and a 19% increase in the risk of a composite event (p = .021).

CONCLUSION

ETLV is prevalent in the pediatric HT population with increased frequency of poor outcomes in those with SD ≥3. ETLV is an easily accessible marker with which to risk-stratify patients.

Remote intervention engagement and outcomes in the Clinical Trials in Organ Transplantation in Children consortium multisite trial

Remote interventions are increasingly used in transplant medicine but have rarely been rigorously evaluated. We investigated a remote intervention targeting immunosuppressant management in pediatric lung transplant recipients. Patients were recruited from a larger multisite trial if they had a Medication Level Variability Index (MLVI) ≥2.0, indicating worrisome tacrolimus level fluctuation. The manualized intervention included three weekly phone calls and regular follow-up calls. A comparison group included patients who met enrollment criteria after the subprotocol ended. Outcomes were defined before the intent-to-treat analysis. Feasibility was defined as ≥50% of participants completing the weekly calls. MLVI was compared pre- and 180 days postenrollment and between intervention and comparison groups. Of 18 eligible patients, 15 enrolled. Seven additional patients served as the comparison. Seventy-five percent of participants completed ≥3 weekly calls; average time on protocol was 257.7 days. Average intervention group MLVI was significantly lower (indicating improved blood level stability) at 180 days postenrollment (2.9 ± 1.29) compared with pre-enrollment (4.6 ± 2.10), p = .02. At 180 days, MLVI decreased by 1.6 points in the intervention group but increased by 0.6 in the comparison group (p = .054). Participants successfully engaged in a long-term remote intervention, and their medication blood levels stabilized. NCT02266888.

Retrospective Analysis of Tacrolimus Intrapatient Variability as a Measure of Medication Adherence

Background:

Increased intrapatient variability (IPV) in tacrolimus levels is associated with graft rejection, de novo donor-specific antibodies, and graft loss. Medication nonadherence may be a significant contributor to high IPV.

Objective:

The objective of this study is to determine the utility of tacrolimus IPV in detecting nonadherence by examining the relationship between self-reported adherence and tacrolimus coefficient of variability (COV), a measure of IPV.

Design:

Retrospective cohort study.

Setting:

St. Michael’s Hospital, Toronto, Ontario.

Patients:

All patients who were at least 1-year post-kidney transplant as of March 31, 2019, prescribed tacrolimus as an immunosuppressant and had a self-reported adherence status. Patients were excluded from the primary analysis of examining the correlation between COV and self-reported adherence if they lacked a calculatable COV.

Measurements:

Self-reported adherence, COV, demographic data, transplant, and medication history.

Methods:

A modified Basel Assessment of Adherence to Immunosuppressive Medications Scale (BAASIS) administered by healthcare professionals to assess self-reported adherence was used. The COV of tacrolimus trough levels was calculated and its correlation to BAASIS response was noted. The median COV was used as a cutoff to examine the characteristics of patients deemed “high COV” and “low COV.”

Results:

A total of 591 patients fit the initial criteria; however, only 525 had a recent calculatable COV. Overall, 92.38% of the population were adherent by self-report. Primary analysis identified a COV of 25.2% and 29.6% in self-reported adherent and nonadherent patients, respectively, though the result was not significant (P = .2). Secondary analyses showed a significant correlation between younger age at transplant and at the time of adherence self-reporting with nonadherence (P = .01). In addition, there was a strong correlation between those nonadherent with routine post-transplant blood work and younger age (P < .01).

Limitations:

The limitations included modified nonvalidated BAASIS questionnaire, social desirability bias, BAASIS only administered in English, and patients with graft failure not active in clinic not being captured.

Conclusions:

The COV should not be used as the sole method for determining medication adherence. However, COV may have some utility in capturing individuals who are not adherent to their blood work or patients who are having a poor response to tacrolimus and should be switched to another medication.

Association Between Neighborhood-level Socioeconomic Deprivation and the Medication Level Variability Index for Children Following Liver Transplantation

BACKGROUND

Neighborhood socioeconomic deprivation is associated with adverse health outcomes. We sought to determine if neighborhood socioeconomic deprivation was associated with adherence to immunosuppressive medications after liver transplantation.

METHODS

We conducted a secondary analysis of a multicenter, prospective cohort of children enrolled in the medication adherence in children who had a liver transplant study (enrollment 2010-2013). Participants (N = 271) received a liver transplant ≥1 year before enrollment and were subsequently treated with tacrolimus. The primary exposure, connected to geocoded participant home addresses, was a neighborhood socioeconomic deprivation index (range 0-1, higher indicates more deprivation). The primary outcome was the medication level variability index (MLVI), a surrogate measure of adherence to immunosuppression in pediatric liver transplant recipients. Higher MLVI indicates worse adherence behavior; values ≥2.5 are predictive of late allograft rejection.

RESULTS

There was a 5% increase in MLVI for each 0.1 increase in deprivation index (95% confidence interval, -1% to 11%; P = 0.08). Roughly 24% of participants from the most deprived quartile had an MLVI ≥2.5 compared with 12% in the remaining 3 quartiles (P = 0.018). Black children were more likely to have high MLVI even after adjusting for deprivation (adjusted odds ratio 4.0 95% confidence interval, 1.7-10.6).

CONCLUSIONS

This is the first study to evaluate associations between neighborhood socioeconomic deprivation and an objective surrogate measure of medication adherence in children posttransplant. These findings suggest that neighborhood context may be an important consideration when assessing adherence. Differential rates of medication adherence may partly explain links between neighborhood factors and adverse health outcomes following pediatric liver transplantation.

Machine learning-based prediction of health outcomes in pediatric organ transplantation recipients

OBJECTIVES

Prediction of post-transplant health outcomes and identification of key factors remain important issues for pediatric transplant teams and researchers. Outcomes research has generally relied on general linear modeling or similar techniques offering limited predictive validity. Thus far, data-driven modeling and machine learning (ML) approaches have had limited application and success in pediatric transplant outcomes research. The purpose of the current study was to examine ML models predicting post-transplant hospitalization in a sample of pediatric kidney, liver, and heart transplant recipients from a large solid organ transplant program.

MATERIALS AND METHODS

Various logistic regression, naive Bayes, support vector machine, and deep learning (DL) methods were used to predict 1-, 3-, and 5-year post-transplant hospitalization using patient and administrative data from a large pediatric organ transplant center.

RESULTS

DL models generally outperformed traditional ML models across organtypes and prediction windows with area under the receiver operating characteristic curve values ranging from 0.750 to 0.851. Shapley additive explanations (SHAP) were used to increase the interpretability of DL model results. Various medical, patient, and social variables were identified as salient predictors across organ types.

DISCUSSION

Results demonstrate the utility of DL modeling for health outcome prediction with pediatric patients, and its use represents an important development in the prediction of post-transplant outcomes in pediatric transplantation compared to prior research.

CONCLUSION

Results point to DL models as potentially useful tools in decision-support systems assisting physicians and transplant teams in identifying patients at a greater risk for poor post-transplant outcomes.

Transplantation and Adherence: Evaluating Tacrolimus Usage in Pediatric Patients With Cancer

BACKGROUND

Researchers have estimated that about 50% of pediatric patients with chronic illness adhere to tacrolimus therapy, a medication responsible for preventing critical side effects in patients undergoing hematopoietic stem cell transplantation (HSCT).

OBJECTIVES

The purpose of this study was to describe patient adherence to tacrolimus by reviewing documentation from the electronic health record and therapeutic drug levels.

METHODS

This retrospective descriptive study examined 357 clinic visits by 57 patients undergoing HSCT. Direct (tacrolimus levels) and indirect (subjective reporting) measures were evaluated.

FINDINGS

The authors found that, in 51% of visits, adherence was not documented. The overall nontherapeutic drug level rate was 60%. Because of the small sample size, nonadherence did not statistically correlate with nontherapeutic levels. The findings highlight the need for adherence awareness, assessment, and documentation in clinical practice.

Late T cell-mediated rejection may contribute to poor outcomes in adolescents and young adults with liver transplantation

Although poor long-term graft survival in LT in AYA is recognized, detailed epidemiological data are still lacking. L-TCMR may have poor outcomes. This study aimed to provide a detailed, epidemiological assessment of the association between AYA age and rejection. L-TCMR was defined in this study as TCMR with central vein or perivenular inflammation occurring later than 3 months after LT. A total of 342 patients who survived for at least 3 months after LT between 2005 and 2015 were enrolled. The AYA group (10-24 years) was compared with the C group (less than 10 years), and the incidence and outcomes of L-TCMR were analyzed. In total, 342 patients had LT; 38 of these were AYA with the mean follow-up period of 6.7 years. A total of 304 patients in C group had a mean follow-up period of 6.3 years (P = .28). The incidence of L-TCMR in AYA group was significantly higher than in C group (15.8% vs 4.6%, P = .006). The time to L-TCMR after LT was significantly shorter in AYA group (P = .01). Neither patient survival nor the incidence of non-adherence differed significantly between the groups (P = .18 and P = .89). The number of additional immunosuppressants after L-TCMR was significantly higher in the AYA group (P = .04). A high incidence of L-TCMR was observed in AYA group irrespective of non-adherence. AYA patients with L-TCMR should be followed carefully due to the poor results of post-treatment biopsy and the need for intensive immunosuppressive therapy.

Implementing a Process to Systematically Identify and Address Poor Medication Adherence in Pediatric Liver Transplant Recipients

Objectives

Poor adherence to medication following pediatric liver transplantation remains a major challenge, with some estimates suggesting that 50% of adolescent liver transplant recipients exhibit reduced medication adherence. To date, no gold standard has emerged to address this challenge; however, system interventions are most likely to be successful. We sought to implement a system to identify and address adherence barriers in a liver transplant clinic.

Methods

Using structured quality improvement methods, including multiple plan-do-study-act cycles, we developed a system to screen for patients at risk of poor adherence, identify patient- and/or parent-reported barriers to adherence, and partner with patients to overcome identified barriers. We developed a process to track key outcomes, including the variability in tacrolimus trough levels and episodes of late acute cellular rejection.

Results

The practice saw a total of 85 patients over 6 months, and about half were females. Over this period, the improvement team implemented this system-level process with high reliability (>90% of patients received the bundle of interventions). The most commonly identified adherence barrier by patients and caregivers was "forgetting." The second most commonly identified adherence barrier by patients was that the medication "gets in the way of their activities," whereas by caregivers, it was "difficulty swallowing pills."

Discussion

We identified challenges and opportunities to screen for poor adherence and identify patient- and/or caregiver-reported barriers to immunosuppression adherence. Identifying such barriers and partnering with patients to overcome those barriers using patient-centered, barrier-specific interventions could improve long-term graft survival through improved medication adherence.

Tacrolimus variability is associated with de novo donor-specific antibody development in pediatric renal transplant recipients

BACKGROUND

Donor-specific antibody (DSA) is a risk factor for antibody-mediated rejection and shortened graft survival. We investigated the role of intrapatient variability in tacrolimus trough levels on graft outcomes (i.e., de novo DSA, rejection, graft loss) in pediatric renal transplant recipients.

METHODS

This was a single-center retrospective study which included 38 pediatric renal transplant recipients. Intrapatient tacrolimus variability was defined using the coefficient of variation (CV; SD/Mean × 100) for all levels obtained after 3 months post-transplant. CV cut-points of 30%, 40%, and 50% were used in the analyses.

RESULTS

The median CV 43.1% (35.0%, 58.6%). Out of 38 patients, 19 (50%) developed de novo DSA. In the logistic regression model, after adjusting for age, rejection history, maintenance immunosuppression, and CV, for every 10% increase in tacrolimus variability, the odds of developing de novo DSA increased by 53% (p = 0.048, CI 1.0005, 1.11). Age at transplant was also an independent risk factor for DSA development; every 1 year increase in age was associated with a 31% increase in the odds of developing DSA (p = 0.03, CI 1.03, 1.67). At a CV cut-point ≥ 30%, higher tacrolimus variability was associated with an increased incidence of allograft rejection (0% vs 42%, < 30 and ≥ 30% respectively, p = 0.07). As there were few graft loss events (n = 4) in our study population, an association could not be determined between tacrolimus variability and graft loss.

CONCLUSION

Tacrolimus variability and age at transplant were identified as independent risk factors for de novo DSA development. There was an association between tacrolimus variability and rejection in pediatric renal transplant recipients. Adding the assessment of tacrolimus variability to current monitoring methods may be an important step towards improving graft outcomes.

Increasing Time in Therapeutic Range of Tacrolimus in the First Year Predicts Better Outcomes in Living-Donor Kidney Transplantation

Background: The aim of the present study was to investigate the impact of time in therapeutic range TTR on long-term outcomes of living kidney transplants.

Methods: We included 1,241 living kidney transplants and randomized them into development and validation cohorts with a ratio of 2:1. The tacrolimus TTR percentage was calculated by linear interpolation with a target range (5–10 ng/ml months 0–3, 4–8 ng/ml months 4–12). The optimal TTR cutoff was estimated by the receiver operating characteristic curve analysis on the basis of acute rejection (AR) within 12 months in the development cohort. Outcomes were analyzed between patients with high TTR and low TTR in the development and validation cohorts, respectively. The TTR was also compared with other tacrolimus measures.

Results: The optimal TTR cutoff value was 78%. In the development cohort, patients with TTR > 78% had significantly higher rejection- and infection-free survival. TTR < 78% was an independent risk factor for AR (OR: 2.97, 95%CI: 1.82–4.84) and infection (OR: 1.55, 95%CI: 1.08–2.22). Patient and graft survival were significantly higher in those with TTR>78%, and TTR<78% was associated with graft loss (OR: 3.2, 95%CI: 1.38–7.42) and patient death (OR: 6.54, 95%CI: 1.34–31.77). These findings were confirmed in the validation cohort. Furthermore, we divided all included patients into a high and low TTR group. TTR was more strongly associated with patient and graft survival than mean level, standard deviation, and intrapatient variability (IPV).

Conclusions: Increasing the TTR of tacrolimus in the first year was associated with improved long-term outcomes in living kidney transplants, and TTR may be a novel valuable strategy to monitor tacrolimus exposure.

Medication non-adherence after kidney transplantation: A critical appraisal and systematic review

Medication non-adherence is one of the most important causes for shortened graft survival subsequently leading to a reduction in kidney graft survival results. Our aim was to provide an overview of its prevalence, risk factors, diagnostic methods and interventions to improve adherence in kidney transplant recipients. Therefore, we systematically searched the databases PubMed, COCHRANE Library, Web of Science and EMBASE for studies addressing "medication adherence", "compliance", "adherence", "kidney transplantation" and "life style factors". We identified 96 studies that satisfied our inclusion criteria. A problematic lack of a uniformly accepted definition for non-adherence was found, consequently leading to a wide range in non-adherence prevalence (36-55%). Using one uniformly accepted non-adherence definition should therefore be encouraged. A wide range in diagnostic methods makes it difficult to accurately detect non-adherence. Heterogeneous results of intervention studies make it difficult to select the best adherence enhancing method, challenging the battle against medication non-adherence. Literature suggests a combination of personalized interventions, based on patient-specific non-adherent behavior, to be most successful in improvement of adherence. High quality diagnostic methods and multidisciplinary, personalized interventions with focus on relevant clinical outcome are essential in overcoming medication non-adherence in kidney transplant recipients.

Gender Differences in Medication Adherence Among Adolescent and Young Adult Kidney Transplant Recipients

BACKGROUND

Among kidney transplant recipients, gender differences in medication adherence may contribute to higher graft failure risks observed in girls and young women compared with boys and young men. Our aim was to determine whether adherence differs by gender, and whether gender differences vary by age in adolescent and young adult kidney transplant recipients.

METHODS

We examined data from the 3-month run-in period (no intervention) of the randomized Teen Adherence in Kidney transplant Effectiveness of Intervention trial. Adherence was monitored using electronic pillboxes in 136 patients (11-24 y) followed in 8 transplant centers in Canada and the United States. We used ordinal logistic regression with generalized estimating equations to estimate the association between gender and each of daily taking (proportion of prescribed doses taken) and timing (proportion of prescribed doses taken on time) adherence, considering effect modification by age (11-16 y vs 17-24 y).

RESULTS

No difference in taking adherence was observed by gender among participants aged 11 to 16 years (odds ratio [OR], 0.92; 95% confidence interval [CI], 0.55-1.54), whereas among participants aged 17 to 24 years, women had significantly greater odds of higher taking adherence scores (OR, 3.03; 95% CI, 1.20-7.66) than men. Results were similar for timing adherence, with no difference among participants aged 11 to 16 years (OR, 1.03; 95% CI, 0.65-1.63) but a greater odds of higher timing adherence scores in women than in men among participants aged 17 to 24 years (OR, 3.26; 95% CI, 1.43-7.45). There were no differences in adherence assessed by self-report or SD of tacrolimus trough levels.

CONCLUSIONS

Gender differences in adherence vary by age. Whereas younger adolescents show no adherence differences by gender, young women show much better adherence than young men.

The Medication Level Variability Index (MLVI) as a potential predictive biomarker of graft-versus-host disease in pediatric hematopoietic stem cell transplant patients

The purpose of this study was to examine the potential predictive value of the Medication Level Variability Index (MLVI) biomarker with graft-versus-host disease (GVHD) in the pediatric hematopoietic stem cell transplant (HSCT) patient during the acute phase post-transplant. This retrospective descriptive study evaluated a total of 406 tacrolimus levels in 64 patients over a varying number of weeks per participant (median = 8, min = 3, max = 11). Patients were followed until Day 100 post-transplant or tacrolimus taper began. A total of 72 episodes of non-therapeutic levels occurred during the acute phase. Of those, 40 (56%) were <5, while 32 (44%) were >15. Approximately 39% (n = 25 of 64) of the participants in the study developed GVHD post-discharge. Those with GVHD had a statistically significantly higher MLVI than those that did not (median = 3.1, IQR = 2.5-4.7 vs 2.3, IQR = 1.6-3.4, respectively, P = 0.024). Using a criterion of MLVI > 3, there was a statistically significant increased likelihood of GVHD (OR = 3.82, 95% CI=1.32 = 11.04, P = 0.013). Area under the curve (AUC) calculation for the sensitivity and specificity of using the MLVI for GVHD was also conducted. The AUC of 0.67 was statistically significant (95% CI 0.53-0.81, P = 0.024). This is the first-known study to report the use of the MLVI in HSCT patients. The MLVI is associated with a main adverse outcome related to HSCT, GVHD. These results are encouraging of a new potential biomarker to evaluate tacrolimus serum assay levels and identify patients at risk for developing GVHD.

Intra-patient variability in tacrolimus exposure in pediatric liver transplant recipients: Evolution, risk factors, and impact on patient outcomes

BACKGROUND

This study aims to investigate the evolution and factors associated with TAC IPV and its impact on patient outcomes in pediatric LT recipients.

METHODS

This is a retrospective study including 41 children. The TAC IPV was expressed as the coefficient of variation and was calculated for years 1-5 following LT. The number of missed clinic appointments was used as a surrogate marker for therapy adherence.

RESULTS

We identified a decrease in the TAC IPV during the first 3 years after LT (P < 0.01). Serum albumin in the first year (P = 0.03), hematocrit (P = 0.02) and total bilirubin (P = 0.04) in the third year, and therapy adherence (P < 0.01) in the fifth year were associated with TAC IPV. High TAC IPV was associated with biopsy-proven acute allograft rejection (P = 0.04) and the need for biopsy during the first year (P = 0.02). There was a borderline association between TAC IPV and donor-specific antibodies (P = 0.08) and CMV viremia (P = 0.07). High TAC IPV was a predictor of need for liver biopsy and AR with an odds ratio of 1.04 (95% CI 1.0-1.1; P = 0.03) and 1.04 (95% CI 1.0-1.1; P = 0.05), respectively.

CONCLUSIONS

Our results highlight the impact of biological factors on TAC IPV during the early LT follow-up and later also therapy adherence. High TAC IPV may be associated with adverse patient outcomes.

Acute cellular rejection treatment outcomes stratified by Banff grade in pediatric kidney transplant

INTRODUCTION

There are limited data to guide optimal treatment strategies for acute cellular rejection (ACR) based on Banff grade for pediatric kidney transplant recipients. This report reviews a large pediatric transplant center's experience with ACR.

MATERIALS AND METHODS

A retrospective analysis of pediatric kidney transplant recipients at our center from 2007 to 2014 was performed. Primary outcomes were incidence of graft failure and graft function one year following ACR based on Banff grade and treatment received.

RESULTS

A total of 204 patients were reviewed, of which 65 received rejection treatment with either an oral steroid cycle (n = 16), intravenous steroid pulse (n = 28), or anti-thymocyte globulin (rATG, n = 21). Overall, patients received rATG for treatment of more severe rejection associated with impaired graft function and as a group experienced statistically significant improvements in eGFR over the year following treatment, though most did not regain baseline graft function.

DISCUSSION

Our data suggest that rATG is partially effective in treating ACR, but our study was underpowered to determine the effect of different treatments based on Banff grade. Since there is limited literature to guide clinical treatment of ACR in children, large transplant centers should collaborate to evaluate outcomes and establish evidence-based practice.

High Calcineurin Inhibitor Intrapatient Variability Is Associated With Renal Allograft Inflammation, Chronicity, and Graft Loss

Background

High calcineurin inhibitor (CNI) intrapatient variability (IPV) has been associated with poor kidney allograft outcomes. However, the relationship between early allograft histological changes, their progression, and CNI-IPV is less well studied. Hence, we evaluated effect of CNI-IPV defined by the degree of fluctuation of CNI levels in all kidney transplant patients over 2 to 12 months posttransplant on early allograft inflammation, subsequent chronicity, and later clinical outcomes.

Methods

Two hundred eighty-six patients transplanted from January 2013 to November 2014 were enrolled with protocol and indication biopsies. The mean CNI-IPV was 28.5% and a quarter of our cohort had IPV of 35% or greater (high CNI IPV). Baseline demographic differences were similar between high and low CNI IPV groups.

Results

High CNI-IPV was associated with a higher incidence of acute rejection (AR) within 1 year (52% vs 31% P < 0.001), more persistent/recurrent AR by 1 year (18.2% vs 6.2%, P = 0.002), higher-grade AR (≥Banff 1B, 27.5% vs 7.3%, P < 0.001), and worse interstitial fibrosis/tubular atrophy (P = 0.005). High CNI-IPV was associated with increased graft loss (GL) and impending graft loss (iGL, defined as eGFR<30 ml/min and >30% decline in eGFR from baseline), regardless of donor-specific antibody, delayed graft function, rejection, or race. In a multivariate Cox Proportional Hazards Model, high CNI-IPV was independently associated with GL + iGL (hazard ratio, 3.1; 95% confidence interval, 1.6-5.9, P < 0.001).

Conclusions

High CNI-IPV within 1 year posttransplant is associated with higher incidence of AR, severe AR, allograft chronicity, GL, and iGL. This represents a subset of patients who are at risk for poor kidney transplant outcomes and potentially a modifiable risk factor for late allograft loss.

Variability of the Mammalian Target of Rapamycin Inhibitors Is Correlated With Long-Term Renal Graft Survival

BACKGROUND

Many studies demonstrate the relationship between the high intrapatient variability of calcineurin inhibitor (CNI) levels and poor long-term renal graft outcome. Our objective is to analyze the intrapatient variability observed in the mammalian target of rapamycin inhibitors (mTOR-i) blood levels, to compare the variability of sirolimus (SRL) with that of everolimus (EVL) in kidney transplant patients converted to an mTOR-i, and to analyze whether the coefficient of variation (CV) was correlated with long-term graft survival.

METHODS

We analyzed 279 adult renal transplant patients converted to an mTOR-i. CV was calculated using at least 3 blood trough levels between 3 and 18 months postconversion.

RESULTS

The mean and median CV of the entire group was 25.54% and 23.7%, respectively. SRL and EVL mean CV was 23.8% and 27.1% (P = .03), respectively. The group of patients into the last tertile with CV> 28.52% presented a lower death-censored graft survival (75.26% vs. 93.01%, P < .0001) with a mean follow-up of 66.5 months.

CONCLUSION

The CV of mTOR-i is correlated with long-term renal graft survival, so it should be considered a prognostic factor. SRL has a lower CV than EVL in renal transplant patients converted to mTOR-i in the stable posttransplant phase.

Psychosocial predictors of medication non-adherence in pediatric organ transplantation: A systematic review

Adherence to immunosuppressant medication is critical to health and quality-of-life outcomes for children who have received a solid organ transplant. Research on the psychological and social predictors of medication adherence is essential to the advancement of pretransplant assessments and transplant psychosocial services. Despite the importance of identifying risk factors, the literature remains limited regarding psychosocial predictors of non-adherence. A systematic search was conducted to identify studies of the psychosocial predictors of post-transplant medication non-adherence in pediatric solid organ transplantation. From 1363 studies identified in searches of empirical literature, a final sample consisted of 54 publications representing 49 unique studies. Findings regarding psychosocial predictors were inconsistent with non-adherence associated largely with adolescence, racial/ethnic minority status, and presence of mental health issues. Familial predictors of non-adherence problems included single-parent households, lower socioeconomic status, lower family cohesion, presence of family conflict, and poor family communication. Several studies reported an association between non-adherence and social pressures (eg, peer social interaction, wanting to feel normal) among adolescent transplant recipients. While significant methodological and substantive gaps remain in this body of knowledge, this review synthesizes current evidence for assessment for transplant clinicians and researchers.

Tacrolimus intra-patient variability is not associated with chronic active antibody mediated rejection

Background

Chronic active antibody mediated rejection (c-aABMR) is a major cause of long-term kidney allograft loss. It is hypothesized that frequent sub-therapeutic exposure to immunosuppressive drugs, in particular tacrolimus (Tac), is a risk factor for the development of c-aABMR. The intra-patient variability (IPV) in Tac exposure may serve as a substitute biomarker for underexposure and/or non-adherence. In this study, the association between Tac IPV and the development of c-aABMR was investigated.

Methods

We retrospectively included 59 patients diagnosed with c-aABMR and compared them to 189 control patients matched for age, year of transplantation and type of kidney donor. The Tac IPV was calculated from pre-dose tacrolimus concentrations measured over a 3 year period preceding the diagnosis of c-aABMR. The mean Tac predose concentrations (C₀), Tac IPV, renal allograft function and graft survival were compared between the groups.

Results

Tac IPV was 24.4% for the cases versus 23.6% for the controls (p = 0.47). The mean Tac C₀ was comparable for the cases (5.8 ng/mL) and control patients (6.1 ng/mL, p = 0.08). Only in the c-aABMR group a significant decline in both mean Tac C₀ and allograft function over the timespan of 3 years was observed (p = 0.03 and p<0.001). Additionally, in the group of c-aABMR patients a high IPV was associated with inferior graft survival (p = 0.03).

Conclusions

A high Tac IPV per se does not predispose to the development of c-aABMR but is associated with inferior graft survival once c-aABMR is diagnosed.

Comparison of the long-term efficacy and safety of generic tacrolimus, Tacrobell, with Prograf in liver transplant recipients

Introduction

The purpose of this study was to compare the safety and efficacy of generic tacrolimus (Tacrobell [TCB]) and a reference tacrolimus (Prograf [PGF]) in liver transplant recipients.

Patients and methods

We retrospectively analyzed 167 patients who used TCB or PGF between January 2009 and March 2016 for >1 year (TCB group, n=86; PGF group, n=81). To assess the efficacy and safety of TCB, we evaluated the relationship between drug dose and trough level, survival, rejection, infection, kidney function, and side effects.

Results

There was no difference in the preoperative demographics between the two groups. Moreover, there was no difference in the drug dose and trough level between the groups at 1 week after surgery. Coefficient of variation (CV) values were obtained at the drug trough level for each patient and no differences in CV values were identified within 1 year (p=0.587) and up to 5 years (p=0.824) in both groups. Rehospitalization (p=0.1) and total rejection (p=0.915) did not differ between the two groups, but the rejection severity, recorded as the rejection activity index value, was worse in the PGF group (p=0.039). No difference was found in the infection rate (p=0.818), and with regard to nephrotoxicity, there was no difference in the rate of patients with chronic kidney disease stage 3 and above during the follow-up period. No differences were found between the two groups in terms of drug side effects and adverse events.

Conclusion

The generic tacrolimus, TCB, is a comparable alternative to the original tacrolimus, PGF, as a main immunosuppressive drug for liver transplantation.

A systematic review of immunosuppressant adherence interventions in transplant recipients: Decoding the streetlight effect

Non-adherence to immunosuppressant medications is an important risk factor for graft dysfunction. To evaluate the effectiveness of adherence-enhancing interventions, we reviewed adherence intervention studies in solid organ transplant recipients (all ages). Using the following databases: PsycINFO, PubMed, Scopus, and ScienceDirect, we identified 41 eligible studies. Only three non-randomized trials showed a possible positive effect on objective indicators of transplant outcomes (such as rejection, liver enzyme levels, kidney function). None of the 21 RCTs showed an improvement in transplant outcomes. Three studies showed a higher rate of adverse events in the intervention group as compared with controls, although this may be related to ascertainment bias. Improvement in adherence as measured indirectly (eg, with electronic monitoring devices) was not aligned with effects on transplant outcomes. We conclude that adherence interventions, to date, have largely been ineffective in improving transplant outcomes. To improve this track record, intervention efforts may wish to concentrate on non-adherent patients (rather than use convenience sampling, which excludes many of the patients who need the intervention), use direct measures of adherence to guide the interventions, and employ strategies that are intensive and yet engaging enough to ensure that non-adherent patients are able to participate.

Variability index of tacrolimus serum levels in pediatric liver transplant recipients younger than 12 years: Non-adherence or risk of non-adherence?

MLVI has been used to assess adherence. To determine the MLVI in children <12 years of age at transplantation and to identify demographic correlates and consequences for the graft. This is a retrospective study of 50 outpatients (4.0 ± 3.5 years), at least 13-month post-liver transplantation. The outcomes evaluated were MLVI, ALT > 60 IU/L, ACR, death, and graft loss. We analyzed demographic and socioeconomic characteristics, indication for transplantation, and type of donor. Student's t test and the chi-square test were used. Statistical significance was set at P ≤ .05. Seventy-two percent were infants or preschoolers, 62% biliary atresia. Seventy-four percent of the mothers had middle-school education, and 54% of the families had an income ≤3632.4 US$/y. Twenty-two (44%) patients had a MLVI ≥ 2 SD; this was more prevalent in families with higher incomes (P = .045). ALT levels > 60 IU/L were more common in MLVI ≥ 2 SD group (P = .035). ACR episodes were similar between groups (P = 1.000). No patient died or lost the graft. MLVI ≥ 2 SD may be an indicator of the risk of medication non-adherence.

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). Four hundred 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. Predefined secondary analyses evaluated other outcomes such as liver enzyme levels, and sensitivity analyses compared adolescents to pre-adolescents. In the primary analysis sample of 379 participants, a higher prerejection MLVI predicted LAR (mean prerejection MLVI with LAR: 2.4 [3.6 standard deviation] versus without LAR, 1.6 [1.1]; p = 0.026). Fifty-three percent 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.

Longitudinal study on the use of dried blood spots for home monitoring in children after kidney transplantation

The use of DBSs for home monitoring has been limited due to unsatisfactory blood sampling and analytical difficulties. The aim of this longitudinal feasibility trial was to assess the utility of DBS to monitor TAC and Cr at home in transplant recipients. A total of 30 participants (2-21 years, mean±SD, 13.6±5.4 year) were enrolled over 12 months. Eighteen were males. Monthly DBS samples were obtained at home and mailed to the central laboratory for analysis of TAC and Cr. Nineteen patients completed the study, and 216 cards were received in the laboratory from a total of 279 cards expected, with 416/519 (80%) blood spots being suitable for analysis. We found a high correlation between blood TAC and Cr levels by DBS and the clinical laboratory, R² =.81 and .95, respectively. Fifteen parents and 15 youth completed measures of satisfaction with and preference for DBS testing. All but one parent/caregiver and youth reported satisfaction and preference for this method of testing over laboratory blood draws. We conclude that home DBS monitoring is a feasible method to monitor TAC and Cr in pediatric transplant recipients.

Operational tolerance in kidney transplantation and associated biomarkers

In the 1960s, our predecessors won a historical battle against acute rejection and ensured that transplantation became a common life-saving treatment. In parallel with this success, or perhaps because of it, we lost the battle for long-lived transplants, being overwhelmed with chronic immune insults and the toxicities of immunosuppression. It is likely that current powerful treatments block acute rejection, but at the same time condemn the few circulating donor cells that would have been able to elicit immunoregulatory host responses towards the allograft. Under these conditions, spontaneously tolerant kidney recipients - i.e. patients who maintain allograft function in the absence of immunosuppression - are merely accidents; they are scarce, mysterious and precious. Several teams pursue the goal of finding a biomarker that would guide us towards the 'just right' level of immunosuppression that avoids rejection while leaving some space for donor immune cells. Some cellular assays are attractive because they are antigen-specific, and provide a comprehensive view of immune responses toward the graft. These seem to closely follow patient regulatory capacities. However, these tests are cumbersome, and require abundant cellular material from both donor and recipient. The latest newcomers, non-antigen-specific recipient blood transcriptomic biomarkers, offer the promise that a practicable and simple signature may be found that overcomes the complexity of a system in which an infinite number of individual cell combinations can lead possibly to graft acceptance. Biomarker studies are as much an objective - identifying tolerant patients, enabling tolerance trials - as a means to deciphering the underlying mechanisms of one of the most important current issues in transplantation.

Within-Patient Variability in Tacrolimus Blood Levels Predicts Kidney Graft Loss and Donor-Specific Antibody Development

BACKGROUND

Lack of adherence to immunosuppressive drugs is a risk factor for development of de novo donor-specific antibodies (dnDSA) and can contribute to antibody-mediated rejection and graft loss. Moreover, nonadherence is the main determinant of immunosuppressive drug level variability. High intrapatient variability of tacrolimus relates to a worse outcome in transplant recipients through unknown mechanisms. We hypothesized that a high within-patient variability of tacrolimus could increase the rate of dnDSA development and contribute to further death-censored graft loss (DCGL).

METHODS

We included 310 adult renal transplants receiving twice-daily tacrolimus throughout their first posttransplant year, with (1) at least 3 blood trough levels available to calculate coefficient of variation (CV) from month 4 to 12, (2) graft survival longer than 1 year, and (3) absence of pretransplant DSA. The dnDSA were analyzed in sera at 1, 3, and 5 years and around 6 month before the last follow-up visit or graft loss by single-antigen beads.

RESULTS

During the follow-up, 53 patients lost their graft excluding death. A total of 116 patients (37.4%) had a CV greater than 30% and 39 (12.6%) developed dnDSA. Coefficient of variation greater than 30% (hazards ratio, 2.613; 95% confidence interval, 1.361-5.016; P = 0.004) independently related to DCGL. Acute rejection, re-transplant and CV greater than 30% (hazards ratio, 2.925; 95% confidence interval, 1.473-5.807; P = 0.002) were the only variables related to dnDSA development by Cox regression analysis.

CONCLUSIONS

Tacrolimus level variability is a strong risk factor for dnDSA development and DCGL. Variability must be added to the current monitoring of kidney transplant recipients due to its relationship with adherence and to graft outcome.

Medication adherence and rejection rates in older vs younger adult liver transplant recipients

A growing number of older adults are undergoing liver transplantation (LT) in the United States. In some settings, it is thought that adherence declines with age. This retrospective study examined adherence and clinical outcomes in older vs younger adult LT recipients. Medical records of adult LT recipients from 2009 to 2012 from a single urban center were reviewed. The medication level variability index (MLVI) was the predefined primary outcome, with nonadherence defined as MLVI >2.5. The secondary outcome was incidence of rejection. Outcomes were evaluated starting 1 year post-LT until 2015. A total of 42 of 248 patients were ≥65 at transplant. Older adults had significantly better adherence than younger ones (65%≥65 were adherent vs 42% younger adults; chi-square two-tailed P=.02). Survival analyses of rejection between age groups censored by time since transplant showed no difference among the four age groups (χ² =0.84, P=.84). Older age was not found to be a risk factor for reduced adherence or graft rejection in patients surviving at least 1 year post-LT.

Using Artificial Intelligence to Reduce the Risk of Nonadherence in Patients on Anticoagulation Therapy

BACKGROUND AND PURPOSE

This study evaluated the use of an artificial intelligence platform on mobile devices in measuring and increasing medication adherence in stroke patients on anticoagulation therapy. The introduction of direct oral anticoagulants, while reducing the need for monitoring, have also placed pressure on patients to self-manage. Suboptimal adherence goes undetected as routine laboratory tests are not reliable indicators of adherence, placing patients at increased risk of stroke and bleeding.

METHODS

A randomized, parallel-group, 12-week study was conducted in adults (n=28) with recently diagnosed ischemic stroke receiving any anticoagulation. Patients were randomized to daily monitoring by the artificial intelligence platform (intervention) or to no daily monitoring (control). The artificial intelligence application visually identified the patient, the medication, and the confirmed ingestion. Adherence was measured by pill counts and plasma sampling in both groups.

RESULTS

For all patients (n=28), mean (SD) age was 57 years (13.2 years) and 53.6% were women. Mean (SD) cumulative adherence based on the artificial intelligence platform was 90.5% (7.5%). Plasma drug concentration levels indicated that adherence was 100% (15 of 15) and 50% (6 of 12) in the intervention and control groups, respectively.

CONCLUSIONS

Patients, some with little experience using a smartphone, successfully used the technology and demonstrated a 50% improvement in adherence based on plasma drug concentration levels. For patients receiving direct oral anticoagulants, absolute improvement increased to 67%. Real-time monitoring has the potential to increase adherence and change behavior, particularly in patients on direct oral anticoagulant therapy.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT02599259.

Immunosuppression in pediatric liver transplant recipients: Unique aspects

Pediatric liver transplantation has experienced improved outcomes over the last 50 years. This can be attributed in part to establishing optimal use of immunosuppressive agents to achieve a balance between minimizing the risks of allograft rejection and infection. The management of immunosuppression in children is generally more complex and can be challenging when compared with the use of these agents in adult liver transplant patients. Physiologic differences in children alter the pharmacokinetics of immunosuppressive agents, which affects absorption, distribution, metabolism, and drug excretion. Children also have a longer expected period of exposure to immunosuppression, which can impact growth, risk of infection (bacterial, viral, and fungal), carcinogenesis, and likelihood of nonadherence. This review discusses immunosuppressive options for pediatric liver transplant recipients and the unique issues that must be addressed when managing this population. Further advances in the field of tolerance and accommodation are needed to relieve the acute and cumulative burden of chronic immunosuppression in children. Liver Transplantation 23 244-256 2017 AASLD.

Automated Reminders and Physician Notification to Promote Immunosuppression Adherence Among Kidney Transplant Recipients: A Randomized Trial

BACKGROUND

Immunosuppression nonadherence increases the risk for kidney transplant loss after transplantation. Wireless-enabled pill bottles have created the opportunity to monitor medication adherence in real time. Reminders may help patients with poor memory or organization. Provision of adherence data to providers may motivate patients to improve adherence and help providers identify adherence barriers.

STUDY DESIGN

Randomized controlled trial.

SETTING & PARTICIPANTS

Kidney transplant recipients (n=120) at a single center.

INTERVENTION

Participants were provided wireless pill bottles to store tacrolimus and record bottle openings. Participants were randomly assigned 1:1:1 to adherence monitoring with customized reminders (including alarms, texts, telephone calls, and/or e-mails), monitoring with customized reminders plus provider notification (every 2 weeks, providers received notification if adherence decreased to <90% during that period), or wireless pill bottle use alone (control).

OUTCOMES

The main outcome was bottle-measured tacrolimus adherence during the last 90 days of the 180-day trial. A secondary outcome was tacrolimus whole-blood concentrations at routine clinical visits.

MEASUREMENTS

Adherence for the primary outcome was assessed via wireless pill bottle openings.

RESULTS

Mean participant age was 50 years; 60% were men, and 40% were black. Mean adherence was 78%, 88%, and 55% in the reminders, reminders-plus-notification, and control arms (P<0.001 for comparison of each intervention to control). Mean tacrolimus levels were not significantly different between groups.

LIMITATIONS

The study did not assess clinical end points. Participants and study coordinators were not blinded to intervention arm.

CONCLUSIONS

Provider notification and customized reminders appear promising in helping patients achieve better medication adherence, but these strategies require evaluation in trials powered to detect differences in clinical outcomes.

Sirolimus and tacrolimus coefficient of variation is associated with rejection, donor-specific antibodies, and nonadherence

BACKGROUND

Immunosuppression medication nonadherence has been associated with donor-specific antibodies and treatment-refractory rejection. Drug-level monitoring is a practical direct marker for nonadherence, as variations indicate erratic ingestion of medication. We previously reported that high variability in tacrolimus trough levels determined by the percent coefficient of variation (CV %) and standard deviation (SD) were associated with biopsy-proven rejection. We hypothesized that the CV % and SD in patients on a sirolimus/low-dose tacrolimus regimen may associate with self-reported medication nonadherence, rejection and donor-specific antibodies.

METHODS

In this pilot feasibility study, we studied 37 biopsies in 23 pediatric renal transplant patients on both sirolimus and tacrolimus immunosuppression; CV %, SD, de novo donor-specific antibodies, rejection, and self-reported adherence were examined.

RESULTS

A cut-off sirolimus CV % of 25 maximized the percentage of biopsies correctly classified as rejection (32 of 37, or 86 %, p = 0.001). A cut-off tacrolimus CV % of 31 maximized the percentage of correctly classified biopsies (25 of 37, or 68 %, p = 0.09). Among patients with both high sirolimus and tacrolimus CV %, 67 % developed de novo donor-specific antibodies (p = 0.002) with a DQ predominance and 71 % reported nonadherence (p = 0.05).

CONCLUSIONS

In pediatric renal transplantation, sirolimus and tacrolimus CV % is a potential tool for monitoring patients at risk for allograft rejection and donor-specific antibodies secondary to medication nonadherence.

Monitoring drug adherence

TOPIC

Medication nonadherence is prevalent in transplant recipients and is a major reason for graft loss. The present review discusses the measurement of adherence in transplant recipients and strategies to improve adherence. SOURCES REVIEWED: Since adherence research is not confined to transplant recipients, our literature review included studies relevant to transplant recipients as well as adherence to medical recommendations more generally. We reviewed manuscripts in the English language indexed in PubMed Central, as well as ancillary sources of information such as textbook chapters that are not indexed.

CONCLUSION

There is no consensus in the literature about an optimal way to monitor adherence, nor is there agreement about a preferred management strategy. Until definitive studies demonstrate the effectiveness of intervention strategies, knowledge of the monitoring as well as intervention methods that are described in this review is expected to give practitioners the initial tools to deal with nonadherence as an important aspect of patient care.

Standardized multilevel transition program: Does it affect renal transplant outcome?

The transfer of renal transplant patients from pediatric to adult care is a crucial step with a high risk of subsequent graft loss. Therefore, the transition should be a thoroughly planned, well-designed and multidisciplinary process focused on the individual patient. Our pediatric nephrology department introduced a structured step-by-step transition program supported by a multidisciplinary team of health professionals. The purpose of our study was to determine the effects of the transition program on eGFR and number of ARs in comparison to a group without a transition program at one and three yr after transfer. We conducted a single-center retrospective cohort study of renal transplant patients prior to and after the introduction of the transition program. Multiple regression analysis revealed a significantly lower decline of eGFR in the group with transition program (-11.3 ± 44 mL/min/1.73 m(2) ) compared to the group without transition program (-28.4 ± 33 mL/min/1.73 m(2) ) at three yr after transfer. The number of AR episodes significantly decreased from 34.6% in the group without transition program to 9.1% in the group with transition program. The standardized multilevel transition program seems to have significant positive effects on eGFR and number of AR episodes in renal transplant patients.